Twin Splitter Transmission

Service Manual

T20113
Issue 01 / 2001
Eaton Twin Splitter Transmission

Truck Components Operations Europe

PO Box 11 Worsley
Manchester M28 5GJ
England

Service Manual

5/01
Section 1 General
1/1 Letter and Model Designation
1/2 Technical Data
1/3 Lubrication
1/4 Recommended Lubricants
1/5 Torque Tightening Recommendations
1/7 Disassembly Precautions and Inspection of Expendable Parts
1/9 Reassembly Precautions
1/10 Special Tools

Section 2 Air System

2/1 General Description - 12 Speed
2/2 Single ‘H’ Pattern Gear Change
2/3 Splitter System - Signal Connections
2/4 Filter Pressure Regulator
2/5 Selector Valve Switch
2/6 Selector Valve - Removal and Refitment
2/7 Pulse Unit
2/8 Splitter Shift - Cylinder Operation
2/9 Splitter Cylinder Cover Assembly - Logic Valves
2/10 Splitter Cylinder Cover Assembly - Twin Spool Valves
2/11 Splitter Gear Air Line Connections
2/12 Splitter Air Circuit Diagrams - Logic Valves
2/14 Splitter Air Circuit Diagrams - Twin Spool Valves
2/16 Splitter Cylinder - Disassembly and Reassembly
2/17 Splitter Cylinder Cover - Trouble Shooting Hints

Section 3 Shifting Controls

3/1 Remote Control - Exploded View
3/2 Disassembly of Remote Control (LRC)
3/3 Reassembly of Remote Control (LRC)
3/4 Shift Bar Housing - Exploded View
3/5 Shift Bar Housing Disassembly
3/6 Shift Bar Housing Reassembly
>>>>

5/01
Section 4 Main Transmission
4/1 Auxiliary Section Removal and Disassembly
4/5 Output Shaft and Rear Sliding Gear Removal and Disassembly
4/7 Auxiliary Countershaft Bearing Renewal
4/7 Auxiliary Section Splitter Gears and Sensor Disassembly
4/8 Splitter Gears Reassembly
4/9 Output Shaft and Rear Sliding Gear Reassembly and Installation
4/13 Main Section Disassembly
4/17 Input Shaft Disassembly
4/17 Input Shaft Reassembly
4/19 Reverse Idler Gear Disassembly and Reassembly
4/20 Mainshaft Disassembly
4/24 Mainshaft End Float
4/26 Mainshaft Reassembly
4/36 Main Transmission Reassembly
4/42 Auxiliary Section Reassembly

Section 5 Changing the Input Shaft

5/1 Input Shaft Disassembly
5/2 Input Shaft Reassembly

Section 6 Upshift Brake

6/1 Upshift Brake - Exploded View
6/2 Upshift Brake Disassembly
6/4 Upshift Brake Reassembly

Section 7 PTO Installation

7/1 Fitting Extended Countershaft
7/2 Assembly of Extended Countershaft

<<<<

5/01
Section 1 General

5/01
General
Letter and Model Designation

Example: TS 12612A
TSO 12612A
T - Twin Countershaft
S - Splitter Transmission
O - Overdrive
12 - Code input torque
6 - Design level
12 - Number of forward speeds
A - Specific ratio type

1/1 5/01
General
Technical Data

MODELS TS(O) 11612A, TS(O) 12612A, TS(O) 13612A, TS(O) 15612A

Permissible Torque
TS(O) 11612A 1560 Nm
TS(O) 12612A 1730 Nm
TS(O) 13612A 1815 Nm
TS(O) 15612A 2080 Nm

Weight1) 325 kg

Length2) 745 mm

Oil capacity approx. 12,5 lit

Aux. Drive possibilities

1 x Rear of transmission, lower left
Right side SAE - standard 6 bolt
Bottom SAE - standard 8 bolt

Output speed X Engine

for rear PTO and drive
SAE 6 and 8 bolt 0,51

Clutch Housing SAE 1 or 2 for Pull and Push Clutch

Grey Iron
or
Aluminium

1) excluding oil, clutch housing and controls

2) from front of main case to the mounting face of the output flange (depending on flange fitted)

1/2 5/01
General
Lubrication

Proper Oil Level 2. High engine RPM

Before checking the oil level or refilling, vehicle 3. High ambient temperature
should be on level ground. Make sure that the oil is 4. Restricted air flow around transmission
level with the filler opening. Because you can reach
5. Exhaust system too close to transmission
the oil with your finger does not mean oil is at the
proper level. 6. High housepower, over;drive operation
High operating temperatures may require more
frequent oil changes.
External cooler kits are available to keep the
transmission operating temperature under 120ºC
when the conditions described above are
encountered.
If the tranmission operating angle is more than 12º,
improper lubrication can occur. The operating angle
1. Oil Level 2. Yes 3. No is the transmission mounting angle in the chassis
plus the percent or upgrade (expressed in
Draining Oil degrees).
Drain transmission while oil is warm. To drain oil
remove the drain plug at the bottom of case.
Refilling
Clean the drain plug before re;installing. Clean area
round filler plug. Fill transmission to the level of the
filler opening.
The exact amount of oil will depend on the
transmission inclination. In every instance, fill to the 1. Max. Operating Angle
level of the filler opening. Do not overfill; this will
2. Transmission Mounting Angle
cause oil to be forced out of the case past the
mainshaft and input shaft seals. 3. Percent of grade
Adding Oil
It is recommended that different types and brands Anytime the transmission operating angle of 12° is
of oil are not intermixed because of possible exceeded for an extended period of time the
incompatibility. transmission should be equipped with an oil pump
or cooler kit to ensure proper lubrication.
Operating Temperature
Note the effect low oil levels can have on safe
It is important that the transmission operating operating angles. Allowing the oil level to fall 13
temperature does not exceed 120ºC for an mm (0,5 in) below the filler plug hole reduces the
extended period of time. Operating temperatures degree of grade by approx. 3° (5,5%).
above 120ºC will cause breakdown of oil and
shorten transmission life.
Towing
The following conditions in any combination can
cause operating temperatures of over 120ºC: When towing the vehicle, the propeller shaft
between the axle and transmission must be
1. Operating consistently at road speeds under disconnected.
32 km/h (20 m.p.h.)

1/3 5/01
General
Recommended Lubricants
Only use recommended lubricants to ensure smooth running.

Lubrication Change and Inspection

Highway Use
First 8,000 km Change transmission oil on new units
Every 16,000 km Inspect oil level. Check for leaks.
Every 80,000 km Change transmission oil

Off Highway
First 30 hours Change transmission oil on new unit
Every 40 hours Inspect oil level. Check for leaks
Every 500 hours Change tranmission oil when severe dirt conditions exist
Every 1,000 hours Change transmission oil (normal off-highway use)

Change oil filter element, if so equipped, at each oil change

Type Quality Temperature

Heavy Duty Engine Oil to Specification SAE 50 over -12°C
MIL-L-2104C or MIL-L-46152 SAE 40 over -12°C
or API-SC or API-CC SAE 30 under -12°C
Mineral Gear Oil to Specification SAE 90 over -12°C
API-GL-1 SAE 80 W under -12°C
Mild EP Gear Oil* to Specification SAE 90 from -12°C to 38°C
MIL-L-2105 or API-GL-4 SAE 80 W from -26°C to 21°C
Multi-purpose Gear Oil* to Specification SAE 85 W 140 over -12°C
MIL-L-2105B or MIL-L-2105C SAE 80 W 140 over -26°C
or API-GL-5 SAE 90 from -12°C to 38°C
SAE 80 W 90 from -26°C to 38°C
SAE 80 W from -26°C to 21°C
SAE 75 W from -40°C to -26°C

* These oils are NOT recommended when lubricant operating temperatures are above 110°C.
Note: Synthetic oils are NOT recommended.

1/4 5/01
General
Torque Tightening Recommendations
Screws and Nuts
1. All 1/8" Compression Fittings. 7 to 10 Nm. 8. Shift Bar Housing. 16 Capscrews M10 Thread -
53 to 66 Nm. Thread coated with Loctite.
2. Clutch Housing. 4 Capscrews M12 Thread.
9. Air Filter Bracker. 2 Capscrews M10 Thread - 53
Aluminium Housing: 84 to 96 Nm with Shakeproof
to 66 Nm Spring Lockwashers.
Internal Lockwasher.
10. Filter Pressure Regulator and Pulse Unit. 2
Cast Iron Housing: 96 to 109 Nm with Spring
Capscrews M6 Thread - 11 to 16 Nm. With Spring
Lockwashers.
Lockwashers and Plain Nuts.
3. Clutch Housing. 6 Nuts M16 Thread.
11. Output Shaft. Nut 2" - 16 Thread- 610 to 680
Aluminium Housing: 190 to 203 Nm with Plain Nm. With Nyon Locking Insert or Staking Collar.
Washer and Nylon Locking Nut. Ensure nut is securely staked into the shaft groove.
Cast Iron Housing: 244 to 270 Nm with standard
Nut and Spring Lockwashers.

4. Clutch Housing. 6 Studs - M16 Thread - 12. Auxiliary Housing. 17 Capscres M10 Thread -
minimum 81 Nm, driven until bottomed. Installed 53 to 66 Nm. Spring Lockwashers.
with Loctite 270. 13. Splitter Cylinder Yokes. 2 Yoke Screw 7/16" -
5. Input Shaft Front Bearing Cover. 6 Capscrews 20 Thread -47 to 61 Nm. Secure with Lockwire.
M10 Thread - 53 to 66 Nm. Thread coated with 14. Oil Drain Plug. 3/4" Pipe Thread, 61 to 75 Nm.
Loctite 270.
15. Reverse Idler Shafts. 2 Capscrews M10 Thread
6. 5 Yoke Lockscrews. 7/16" - 20 Thread - 47 to - 53 to 66 Nm. Thread coated with Loctite.
61 Nm secure with Lockwire.
7. Shift Lever Remote Control Housing Studs. 4
M10 Thread - 53 Nm, driven until bottomed.
(Note: Style of Nuts and Washers will vary with
specification.)
1/5 5/01
General

Plunger in Reverse Yoke

1. After installing Plunger and

Spring, tighten Plug and back
off 1/4 to 1/2 Turn. Stake
Threads in Hole.
N.B. Not fitted on SAMT
transmissions.

1. 4 Support Studs. M16 Thread - minimum 81

Nm. Drive until bottomed, installed with Loctite 270.
2. 4 Support Studs Nuts. M16 Thread - 230 to
250 Nm oiled at vehicle location, with Lockwashers.
3. Air Filter Plug. 11/4" - 18 Thread - 23 to 28,5
Nm.
4. Auxiliary Countershaft Rear Bearing Cover.
11 Capscrews M10 Thread - 53 to 66 Nm. Thread
coated with Loctite 270.
12. Speedometer Housing. 1 Capscrew M10
5. Oil Filler Plug. 11/4" Pipe Thread - 81 to 102 Thread - 53 to 66 Nm, with Brass Flatwasher and
Nm. Nylon Seal.
6. Lower P.T.O. Cover. 8 Capscrews M12 Thread - 13. Speedometer Housing. 5 Capscrews M10
96 to 109 Nm. Thread coated with Loctite, Thread - 53 to 66 Nm, Lockwashers.
Lockwashers.
14. Speedometer Housing Plug. 47 to 61 Nm.
7. Splitter Cylinder Cover. 4 Capscrews M10
Thread - 41 to 47 Nm. Thread coated with Loctite. 15. Upshift Brake. 2 Capscrews & 4 Socket head
M10 Thread - 53 to 66 Nm.
8. Cover - Clutch Housing. 4 Capscrews M8
Thread - 29 to 34 Nm. 1 Capscrew (on Keep Plate) M12 Thread - 95,0 to
102,0 Nm.
9. Plug. 9/16 - 18 Thread - 47 to 68 Nm.
2 C/S Screws M8 Thread - 17,0 to 21,0 Nm.
10. Side Power Take Off Cover. 6 Capscrews
M10 Thread - 53 to 66 Nm. Thread coated with
Loctite.
11. Plug. 1/4" Pipe Thread - 13 to 16 Nm.

1/6 5/01
General
Disassembly Precautions Inspection of Expendable Parts

It is assumed in the detailed disassembly Before reassembling the transmission, the

instructions that: The lubricant has been drained. individual parts should be carefully checked to
The necessary linkage and air lines removed from eliminate those damaged. They should be
the chassis. Removal of the gear shift remote renewed. This inspection procedure should be
control housing assembly is included in the detailed carefully followed to ensure the maximum of wear
instructions; however, this assembly must also be life from the rebuilt unit.
removed from transmission before removing unit
The cost of a new part is generally a small fraction
from vehicle.
of the total cost of downtime and labour, should the
Follow each procedure closely in each section, use of a questionable part make additional repairs
making use of both the text and the pictures. necessary before the next reguarly scheduled
overhaul.
1. Cleanliness - Provide a clean place to work. It is
important that no dirt or foreign material enters the Recommended inspection procedures are set forth
unit during repairs. The outside of the unit should in the following check list:
be carefully cleaned before starting the
disassembly. Dirt is abrasive and can damage A. Bearings
bearings. 1. Wash all bearings in clean solvent. Check balls,
2. Bearings - Carefully wash and relubricate all rollers and races for pits and spalled areas. Renew
bearings as removed and protectively wrap until damaged bearings.
ready for use. Remove bearings with pullers 2. Lubricate undamaged bearings and check for
designed for this purpose. axial and radial clearances. Renew bearings with
3. Assemblies - When disassembling the various excessive clearances.
assemblies, such as the mainshaft, countershaft 3. Check fits of bearings in housing bores. If outer
and shift bar housing, lay all parts on a clean races turn too freely in the bores, the housing
bench in the same sequence as removed. This should be renewed. Check housing bores for signs
procedure will simplify reassembly and reduce the of wear prior to taking this action. Only replace
possibility of losing parts. housing if wear is seen as a result of bearing spin.
4. Snap rings - Remove snap rings with pliers B. Gears
designed for this purpose. Rings removed in this
manner may be reused, except where new ones 1. Check gear teeth for pitting of the tooth faces.
are specified in 'Reassembly'. Gears with pitted teeth should be renewed.
5. Input shaft - The drive gear or input shaft can 2. Check all engaging gear teeth. Gears with teeth
be removed without removing the countershaft or worn, tapered or reduced in length from clashing in
mainshaft. Take care not to misplace or lose the shifting should be renewed.
mainshaft spigot thrust races and washers. 3. Check axial clearances of gears. Where
6. When Pressing - Apply force to shafts, housings excessive clearance is found, check gear snap
etc. with restraint. Movement of some parts is ring, washer, spacer and gear hub for excessive
restricted. Do not apply force after the part is wear.
restricted. Do not apply force after the part being Maintain 0.13 to 0.30 mm axial clearance on
driven stops solidly. Use soft hammers and bars for mainshaft forward gears and on reverse gear.
all disassembly work.
C. Bearing Sleeve - Mainshaft
1. Sleeves with groove formation, pits or which
have either been overheated or worn out must be
renewed.
2. Radial clearance between bush and shaft should
be 0.76 mm to 1 mm.

1/7 5/01
General

D. Splines K. Bearing Covers

1. Check splines on all shafts for wear. If sliding 1. Check covers for wear from thrust. Renew
clutch gears, output drive flange or clutch hub have covers worn of grooved from thrust of bearing outer
worn into the sides of the splines, the shafts in this race.
condition must be renewed.
2. Check bores of covers for wear. Renew those
E. Thrust Washers worn oversize.

1. Check surfaces of all thrust washers. L. Oil Return Threads and Seals
Washers scored or reduced in thickness should be 1. Check oil seal in front bearing cover for damage
renewed. and wear, renew if necessary.
F. Reverse Idler Gear 2. Check oil seal in speedometer housing for
damage or wear, renew if necessary. Renew grit
1. Check bearing sleeve for wear from action of shield if worn or loose on flange.
roller bearings.
M. Sensor/Jaw Clutches
G. Grey Iron Parts
1. Check the sensors and jaw clutches for burrs,
1. Check all grey iron parts for cracks and breaks. uneven and excessive wear at contact surface, and
Renew or repair parts found to be damaged. Heavy metal particles. Check the 'gylon' faces for wear or
castings may be welded or brazed providing the damage.
cracks do not extend into bearing bores or bolting
surfaces. 2. Check energiser rings for excessive wear or loss
of tension. Renew if in any doubt.
H. Clutch Release Parts
3. Check sensor contact surfaces on the gears for
1. Check clutch release parts, yokes and bearing excessive wear. If burnt out contact surfaces are
carrier. Check pedal shafts. Renew worn shafts and evident, gears should be renewed.
bearings.
N. Sliding Clutches
I. Shifting Bar Housing
1. Check all yokes and yoke slots in sliding
1. Check yokes and gates for wear at contact clutches for extreme wear or discolouration from
points. Renew worn parts. heat.
2. Check yokes for alignment. 2. Check engaging teeth of sliding clutches for
3. Check yokes for excessive wear, renew worn partial engagement pattern. Clutches with engaging
yokes. teeth worn, tapered or reduced in length from
clashing should be renewed.
4. Check lockscrews in yokes and gates. Tighten
and re-wire those found loose. Lockscrews with O. O-Rings
worn tapers must be renewed. 1. Renew all O-rings.
5. If housing has been dismantled, check neutral
notches of shifting bars for wear from interlock
balls. Bars indented at points adjacent to the
neutral notch should be renewed.
J. Gear Shift Remote Control
1. Check spring tension on shift shaft. Renew
tension spring if shaft moves too freely.
2. If housing is dismantled, check shift shaft and
finger and the sliding bearings for wear. Renew
worn parts.

1/8 5/01
General
Reassembly Precautions

Make sure that interiors of all housings are clean. It bearing, preventing damage to balls and races and
is important that dirt be kept out of transmission maintaining correct bearing alignment with shaft
during reassembly. Dirt is abrasive and can and bore. A Tubular type driver, if used, will apply
damage polished surfaces of bearings and force only to the inner race.
washers. Use certain precautions, as listed below, 7. Output Shaft Drive Flange - Replace any
during reassembly. flanges with worn or damaged seal journals.
1. Gaskets - Use new gaskets throughout the Secure the flange by torqueing the nut to 610 to
transmission as it is being rebuilt. Make sure all 680 Nm.
gaskets are installed, as omission of a gasket can If the nut is a staked nut, ensure that nut is
result in oil leakage or misalignment of bearing adequately staked into the groove on the shaft.
covers. Failure to do this allows the shaft to move axially
2. Capscrews - To prevent oil leakage, use thread resulting in damage to the bearing and mainshaft
sealant on all capscrews. The corresponding torque thrust races.
ratings are to be found in 'Torque Prior to refitting a flange (or yoke) ensure that the
Recommendations for Screws and Nuts'. seal track is not grooved scored or pitted. If in
3. O-Rings - Lubricate all O-rings lightly with doubt, it must be replaced.
silicone lubricant.
4. Initial lubrication - Stick mainshaft thrust race
packs onto mainshaft spigots with petroleum jelly to
assist in preventing them becoming displaced
during reassembly.
5. Axial Clearances - Maintain the axial
clearances of mainshaft forward speed and reverse
gears at 0.13 to 0.30 mm.
6. Bearings - Use of flange-end bearing drivers is
recommended for the instalation of bearings. These
drivers apply equal force to both races of the

1/9 5/01
General
Special Tools

Some illustrations show the use of specialised tools. These tools are recommended for disassembly and
reassembly of the transmission. They make repair easier, faster and prevent damage.
The following tools are available from SPX UK (Ltd) Tel : +44 (0)1327 704461

LC105A Main Tool Assembly LC 204 Dummy Support - Countershaft Rear

Journal

E 105-1 Adaptor Auxiliary Countershaft Rear E 108 Installer Main Tool

Bearing

E 105-2 Adaptor Countershaft Front Bearing E 108-1 Countershaft Front Bearing Installer

E 105-3 Adaptor Countershaft Rear Bearing E 108-2 Output Shaft Bearing Installer

1/10 5/01
General

E 108-3 Countershaft Rear Bearing Installer E 109-3 Input Shaft Bush and Output Shaft Bush
Installer

E 108-4 Oil Seal Installer

E 108-5 Auxiliary Countershaft Bearing and Input

Shaft Bearing Installer E 113 Jaw Clutch Spring Compressor

E 109 Handle - Installer LC 284/11 Rev Idler Shaft Puller Adaptor

E 109-1 Rev Idler Bearing Installer MS 284 Slide Hammer

1/11 5/01
Section 2 Air System

5/01
Air System
General Description
Twin Splitter 12 speed
A = Main section B = Auxiliary section

The Twin Splitter Transmission has a 4 speed main section with an auxiliary section containing 3 splitter
ratios

Main section Auxiliary section

4 forward speeds I Low Each forward gear is split

1 reverse speed II Intermediate three times, giving twelve
III High gears in total

Gear shift by means Pneumatic gear shift

of shift lever by means of a splitter
switch

Air System Maintenance

In order to ensure that the transmission functions
without problems and has a long life, the
compressed air reservoirs on the vehicle must be
drained regularly and the filter on the transmission
cleaned every 80,000 kms (or 6 months). Please
consult the Operating Instructions supplied by the
vehicle manufacturer.

2/1 5/01
Air System
Twin Splitter Single 'H' Pattern

Gearshift

Single 'H' pattern gate, four position plus reverse, three splitter gears available in each position.

Splitter

I Low
II Intermediate
III High

Three position flick-switch, Low (I), Intermediate (II) and High (III), for pre-selection of splitter gears
engaged through throttle operation or clutch control.

2/2 5/01
Air System
Splitter System - Signal Connections

Switch Transmission Connections

Port
No. Overdrive Direct

1 Filter/Regulator Filter/Regulator
3 Exhaust Exhaust
21 Shift Cover 'R' Shift Cover 'R'
22 Shift Cover 'F' Blank Off
23 Blank Off Shift Cover 'F'

Splitter Switch - Signal Pipe Connections

1. Splitter Switch Signal Connection

Transmission Air Connections - Upshaft Brake and Splitter Cylinder

1. 3 Way Pilot Valve to be operated only when the clutch is fully depressed
2. Pulse Unit Supply (5.5 bar)
3. 'R' Port and 'F' Port (shift cover)
4. Air Supply (7-8 bar)
5. Regulated Air (5.5 bar)

2/3 5/01
Air System
Filter Pressure Regulator

Filter Maintenance

1. Filter pressure regulator 6. Plug

2. Filter element 7. Air supply port
3. Seal ring 8. Outlet port *
4. 'O' ring 9. Outlet seal plug *
5. End cap 10. Capscrew with lockwasher

.A. Removal and Disassembly B. Assembly and Installation

1. Remove end cap 1. Renew filter element, seal ring and O ring if
necessary.
2. Remove filter insert from housing and clean.
Cleanser: Soap and water solution, cold cleaner 2. Fit end cap.
etc. Then blow element from inside using 3. Check filter regulator function. Unscrew seal plug
compressed air. (9), attach test connection with gauge.
3. Clean filter regulator housing. Recommended operating pressure 5.34-5.69 bar.

* Alternative positions

2/4 5/01
Air System
Selector Switch
Splitter Ratios

I. Low
II. Intermediate
III. High

Function
Constant air supply to '1' from filter/regulator.

Overdrive Direct
Shift Position I Air supply from 21 to shift cover Air supply from 21 to shift cover 'R'
'R' and from 22 to shift cover 'F'.

Shift Position II Air supply from 22 to shift cover 'F'. No air supply from valve in this position.

Shift Positon III No air supply from valve in this Air supply from 23 to shift cover 'F'.
position.

2/5 5/01
Air System
Selector Valve Removal and Re-fitment

Removal and Disassembly

1. Remove cowl.
2. Disconnect all air lines.
3. Loosen lock nut and unscrew selector valve from
shift lever.
4. To disassemble the valve remove socket head
screw (2).
Note: Take care not to break tang from cap.
5. Thoroughly clean inside of selector valve.

Re-fitment
1. Renew seal ensuring that it is fitted correctly.
2. Smear sealing surface of base using lubricant
supplied in Service Kit.
Caution: Do not use any other type of lubricant.
3. Reassemble valve and tighten socket headed
screw to the correct torque.
4. Screw selector valve onto shift lever and secure
with lock nut.
1. Cowl Note: Only screw down max. 17mm, otherwise the
2. Socket head screw housing will be deformed and the valve will leak.
3. Base 5. Connect all air lines and test for leaks.
4. Seal 6. Refit cowl.
5. Housing Torque:
6. Pressure pad
Socket head screw (No.2) = 10-12 Nm.
7. Anti-rattle spring
Air connection = 2.7-3.4 Nm.
8. Plunger
9. Compression spring
10. Lever Trouble Shooting Hints
11. Cap - Check that valve functions correctly.
12. Lock nut - Check all air connections for leaks.
13. Shift lever
- Remove valve from gear lever and check socket
14. max 17 mm head screw (No.2) for tightness.
- Lubricant (sachet)
- If leaks persist renew the seal (No.4). (Service
Kit No. T20137).

2/6 5/01
Air System
Upshift Clutch Brake - Pulse Unit

1. 3 Way Pilot Valve to be operated only when the clutch s fully depressed
2. Pulse unit supply 1/8 27 N.P.T.F.
3. Air Supply 3/8 - 18 N.P.T.F.
4. Regulated Air 5.5 bar 1/8 N.P.T.F.

A pulse valve gives a controlled pulse of air to the

upshift brake activated by a pilot valve usually fitted
under the clutch pedal.
When the clutch pedal is fully depressed the pulse
unit is activated, giving a single pulse of air for up
to a maximum of 0.45 second.

Trouble Shooting Hints

In case of suspected failure.
1. Check clutch pedal area of cab to ensure that
the pilot valve is able to operate effectively.
2. Check air supply to pulse unit when clutch pedal
is fully depressed.
3. Disconnect the air connection at the upshift
brake. Fully depress the clutch pedal and check
that a pulse of air is being supplied. If no air is
being supplied, renew the pulse unit.

2/7 5/01
Air System
Splitter shift

Cylinder Operation
Constant air is supplied to the shift cylinder cover
port 'S' from the filter/regulator. Pilot signals (to F
and R) from the splitter switch in the cab cause the
valves on the cylinder cover to supply air to the
pistons. Refer to Table 1 and Figures 1 and 2. The
interlock pin prevents both piston shafts being
selected at the same time.

Fig. 1 Overdrive Transmission Fig. 2 Direct Transmission

1. Shift Cylinder Cover 1. Shift Cylinder Cover

2. Intermediate 2. High
3. Interlock Pin 3. Interlock Pin
4. Low 4. Low
5. High 5. Intermediate

Table 1
Overdrive Direct
Splitter/Cylinder A B C A B C

I Low P P E P P E

II Intermediate P E P P E E

III High P E E P E P

P = Pressure, E = Exhaust, see figs, 1 and 2.

2/8 5/01
Air System
Splitter Cylinder Cover Assembly - Logic Valves

The splitter cylinder cover assembly consists of a If signal pressure is applied to port 'F' (and cut off
cast aluminium housing with internal drillings on from port 'R') the 'NOT' unit will open, the left hand
which are mounted three, sealed, air operated logic 'YES' unit will open, the left hand 'YES' unit will
valve units. close and the right hand 'YES' unit will open to give
pressure to port 3 of the splitter cylinder.

All three units are of similar design but perform For individual circuit diagrams, refer to Splitter Air
different functions. Two units are designated YES Circuit Diagrams - Logic Valves: Overdrive
units and the third, a NOT unit. Transmission, Direct Drive Transmission.

The NOT unit is a 'normally open' valve whereby

supply pressure to port 2 (the centre port) holds the
valve open and supplies air straight to output port
3. When a signal pressure supply is applied to port
1 the valve is closed by the opposing air pressure
and port 3 is vented to atmosphere.

The two YES units are identical and each is a

'normally closed' valve whereby the supply
pressure to port 2 holds the valve closed and
prevents air from going to the output port 3 (which
is vented to atmosphere). When a signal pressure
supply is applied to port 1, the opposing air
pressure closes port 3 to atmosphere opens the
valve and air pressure from port 2 is supplied to
port 3.

A constant air pressure to port 'S' supplies ports 2

of both the left hand and right hand 'YES' units and Fig. 1 Splitter Cylinder Cover Internal Drillings
port 1 of the splitter cylinder.
If signal pressure is now applied to ports 'R' and 'F'
the 'NOT' unit is closed and the left hand 'YES' unit
will open to give pressure to port 2 of the splitter
cylinder.

2/9 5/01
Air System
Splitter Cylinder Cover Assembly - Twin Spool Valves

Twin Spool Valve Unit circuit diagram it will be seen that in TSO low, port
'F' also receives signal pressure but this is shut off
The splitter cylinder cover assembly consists of a by the lower spool valve and serves no purpose in
cast aluminium housing containing two glandless this range.
sleeve-and-spool valve assemblies. Each sleeve is
When signal air pressure to port 'R' is shut off and
supported radially and axially in the cover assembly
the line exhausted out of port 3 on the splitter
in 'O' rings, but there are no seals or 'O' rings fitted
selector switch, the lower spool valve returns to the
to the valve spool which relies on extremely close
right under pressure of the spring. This shuts off
tolerances (1 micron) to form the seal between it
the constant air pressure to port 2 of the splitter
and the sleeve, Internal drillings in the housing
cylinder, exhausts the line and also opens the
connect the two valves to one another and the
signal air supply passage from port 'F' to the upper
splitter operating cylinder housing.
spool valve. If signal air pressure is now applied to
port 'F' the upper spool valve is forced to the left
Three ports marked 'S', 'F' and 'R' connect to the against spring pressure and opens the constant air
air supply and the splitter selector switch. supply feed to port 3 on the splitter cylinder.

Port 'S' receives constant air pressure which is

passed to both spool valves and to port 1 of the When signal air pressure is shut off from both 'F'
selector valve. Ports 'F' and 'R' receive signal and 'R' ports, both spool valves are enabled to
control air supply from the selector switch, return to the right under spring pressure and the
depending on its position. lines vented to atmoshere.

The upper, shorter spool valve has a single The mechanical functions within the transmission
chamber and acts as an ON/OFF switch to port 3 are identical whether a logic valve or a spool valve
of the splitter cylinder. assembly is fitted.

The lower, longer, spool valve has two chambers

and performs two functions. The left hand chamber
acts as an ON/OFF switch to port 2 of the splitter
cylinder while the right hand chamber acts as an
ON/OFF switch to control the upper spool valve in
response to signals to ports F and R from the
splitter selector switch.

If signal air pressure is supplied to port 'R' on the

housing, the air pressure forces the lower spool
valve to the left against spring pressure and
uncovers the constant air supply from port 'S' to
give pressure to port 2 of the splitter cylinder. In the

2/10 5/01
Air System
Splitter System - Splitter Gear Air Line Connections

12 Speed Twin Splitter Transmission Models

Overdrive

I. Splitter Switch Connections IV. Filter/Regulator

II. Splitter Shift Cylinder V. Regulated Air (5,5 bar)
III. Filter/Regulator

Direct

I. Splitter Switch Connections IV. Filter/Regulator

II. Splitter Shift Cylinder V. Regulated Air (5,5 bar)
III. Filter/Regulator

2/11 5/01
Air System
Splitter Air Circuit Diagrams - Logic Valves
Overdrive Transmissions

Fig. 1 TSO - Low

1. Filter
2. Regulator
3. Switch
4. Intermediate
5. Interlock Pin
6. Low
7. High
8. Right hand
9. Left hand

Fig. 2 TSO - Intermediate

1. Filter
2. Regulator
3. Switch
4. Intermediate
5. Interlock Pin
6. Low
7. High
8. Right hand
9. Left hand

Fig. 3 TSO - High

1. Filter
2. Regulator
3. Switch
4. Intermediate
5. Interlock Pin
6. Low
7. High
8. Right hand
9. Left hand

2/12 5/01
Air System

Direct Drive Transmission

Fig. 1 TS - Low
1. Filter
2. Regulator
3. Switch
4. High
5. Interlock Pin
6. Low
7. Intermediate
8. Right hand
9. Left hand

Fig. 2 TS - Intermediate
1. Filter
2. Regulator
3. Switch
4. High
5. Interlock Pin
6. Low
7. Intermediate
8. Right hand
9. Left hand

Fig. 3 TS - High
1. Filter
2. Regulator
3. Switch
4. High
5. Interlock Pin
6. Low
7. Intermediate
8. Right hand
9. Left hand

2/13 5/01
Air System
Splitter Air Circuit Diagrams - Twin Spool Valves
Overdrive Transmission

Fig. 1 TSO - Low

1. Low
2. Vent
3. Exhaust
4. Switch
5. Filter
6. Regulator

Fig. 2 TSO - Intermediate

1. Intermediate
2. Vent
3. Exhaust
4. Switch
5. Filter
6. Regulator

Fig. 3 TSO - High

1. High
2. Vent
3. Exhaust
4. Switch
5. Filter
6. Regulator

2/14 5/01
Air System

Direct Drive Transmission

Fig. 1 TS - Low
1. Low
2. Vent
3. Exhaust
4. Switch
5. Filter
6. Regulator

Fig. 2 TS - Intermediate
1. Intermediate
2. Vent
3. Exhaust
4. Switch
5. Filter
6. Regulator

Fig. 3 TS - High
1. High
2. Vent
3. Exhaust
4. Switch
5. Filter
6. Regulator

2/15 5/01
Air System
Splitter Cylinders

Disassembly and Reassembly 2. Carefully install the single piston (with the
shorter shift bar) into the cylinder. Position the
(Cylinder removed from transmission) piston so that the slot is aligned with the interlock
1. Push or tap out the longer shift bar (with the pin bore.
double piston) from the splitter cylinder. 3. Install the interlock pin, pushing it fully home and
2. Push or tap out the second piston from the ensuring that the chamfered end is correctly
splitter cylinder. aligned into the slot in the piston shaft.
3. Remove the interlock pin. 4. Install the inner piston into the second bore,
followed by the outer piston. Push the outer piston
4. Remove the O rings from the cylinder bores and
into by bore until flush with the face of the cylinder.
the sealing rings from the pistons. Clean all parts.
5. Protect the assembly from ingress of dirt until
ready for reinstallation.
Reassembly
1. Assemble the new O rings into the cylinder bores
using a light application of silicone lubricant,
assemble new sealing rings to the pistons using a
light application of silicone lubricant. Excessive
lubricant causes contamination in the splitter valves
and adversely affects the performance.

Splitter Cylinder Assembly - Exploded View

1. Splitter Cylinder 5. Cover assembly 9. Piston

2. Piston 6. Seal ring 10. Interlock pin
3. Seal ring 7. Piston (neutral stop) 11. O ring
4. Gasket 8. Seal ring 12. O ring

2/16 5/01
Air System
Splitter Air Circuit Diagrams - Logic Valves
Troubleshooting Hints To renew a valve unit, remove the two screws and
remove the unit from the splitter cylinder cover
Checking operation of YES and NOT logic valve assembly.
units Note the position of the location pip when installing
Each unit is fitted with two, small, coloured the valve. Always fit new O rings.
indicator plungers, one red and one green.
These indicators 'pop out' approximately 3,0 mm
upon initial application of air pressure and remain
'out' unless pushed back in by hand for
checking/trouble shooting purposes. In all cases
the Red indicator is on the output port 3, and the
Green indicator on the input signal port 1.
Referring to the air circuit diagram it will be seen
that with air pressure to the supply port 'S' only, all
six indicators on the three logic valve units should
be able to be pushed in.
If signal pressure is applied to port 'F' the Red
indicator on the NOT unit and the Green and Red
indicators on the right hand YES unit should 'pop
out' and feel to be under pressure if an attempt is
made to push them back in.
If signal pressure is now also applied to port 'R' as
well as port 'F; the Green indicator on the NOT unit
and the Green Red indicators on the left hand YES
unit should 'pop out' and felt to be under pressure.
Additionally it should now be possible to push in Fig. 1 Splitter Cylinder Cover - Exploded View.
the Red indicator on the NOT unit and the Red and
Green indicators on the right hand YES unit. Table
1 indicates the plungers which should be under
pressure when a particular range is selected.

TSO
NOT L/H YES R/H YES
Low Green Green/Red No
Int Red No Green/Red
High No No No
TS
Low Green Green/Red No
Int No No No
High Red No Green/Red

Table 1: Logic valve units indicator plunger

checking chart

Air leaks from the valve unit exhaust port(s) could

indicate either a leaking valve unit diaphragm or 1. Red 2. Green
valve seat, or a leaking splitter control piston O
ring. Fig. 2 Logic valve units indicator plungers.
If the valve unit is at fault it must be renewed
2/17 5/01
Section 3 Shifting Controls

5/01
Shifting Controls
Shift Bar Housing - Single 'H' Shift

Remote Control (LRC) - Single 'H' Shift - Exploded View

1. Remote Control LRC 15. Gasket

2. Housing 16. Housing Cover, front
3. Gasket 17. Capscrew
4. Sliding Bearing 18. Sliding Bearing
5. Housing Cover, rear 19. Seal Ring
6. Reaction Rod Bracket 20. Bellows
7. Capscrew 21. Pinch Bolt
8. Washer 22. Lever
9. Spring 23. Locknut
10. Shaft with Shift Finger 24. Ball Joint
11. Washer 25. Reaction Rod Ball Joint
12. Stop Ring 26. Locknut
13. Locking Pin 27. Reaction Rod
14. Stop Sleeve 28. Link

3/1 5/01
Shifting Controls
A. Disassembly of Remote Control (LRC)

1. Remove the remote control from the shift bar 4. Drive out the locking pin from the stop ring.
housing, remove the shift lever and reaction rod

2. Remove the housing front cover. 5. Remove the stop ring, spring and lockwasher.

3. Remove the stop sleeve from the housing front 6. Manoeuvre the shift shaft and finger out of the
cover. housing. Remove the housing rear cover and
reaction rod bracket.

3/2 5/01
Shifting Controls
B. Reassembly of Remote Control (LRC)

7. If necessary renew the sliding bearings and the 10. Drive in a new stop ring lock pin.
seal ring in the housing front cover.

8. Fit the housing rear cover and reaction rod 11. Install the stop sleeve into the housing front
bracket. Install the shift shaft and finger into the cover.
housing.

9. Assemble the lockwasher, spring stop washer 12. Install the housing front cover. Refit the shift
and stop ring over the shaft. lever and reaction rod and install the remote
control onto the shift bar housing.

3/3 5/01
Shifting Controls

Shift Bar Housing Assembly - Exploded View

19. Plunger
20. Reverse gear shift yoke
21. Lockscrew
22. 1st/2nd gear selector block
23. Lockscrew
7. Actuating pin 24. 3rd/4th gear selector block
8. Plug - (oil pump or cooler 25. Lockscrew
feed) 26. 3rd/4th gear selector block
9. Plug - (breather) 27. Interlock ball
10. Shift bar housing 28. Interlock pin
11. Gasket 29. 1st/2nd gear shift bar
12. Capscrew (14) 30. Reverse gear shift bar
1. Plug/Neutral Switch 13. Gasket 31. 1st/2nd gear shift yoke
2. Plug/Reverse switch 14. Gasket 32. Lockscrew
3. Detent balls (3) 15. Stud 33. Lockscrew
4. Detent springs (3) 16. Gasket 34. 3rd/4th gear shift yoke
5. Capscrew (2) 17. Plug 35. Actuating plunger - neutral switch
6. Lifting eye 18. Spring Not fitted on SAMT transmissions

3/4 5/01
Shifting Controls
A. Removal and Disassembly

1. Make sure that the shift bars are in the neutral 3. Remove the 1st/2nd selector block lockscrew
position. Remove the three detent springs. slide the yoke with the bar into the aperture and
Remove the retaining capscrews and lift off the remove the yoke lockscrew (from the top side of
shift bar housing. Invert the housing and release the housing). Remove the block, bar gate and
the detent balls by tapping the housing lightly. yoke. As the notch clears the housing remove the
interlock pin from the shift bar.

2. Mount the housing in a vice fitted with protected 4. Remove the 3rd/4th selector block and yoke
jaws, rear end of housing to the left. Cut and lockscrews, remove the yoke. Slide the shift bar
remove all lockwires. Remove the reverse yoke out to the right collecting the two interlock balls.
lockscrews and remove the reverse shift bar and
yoke.

3/5 5/01
Shifting Controls
B. Reassembly and Installation

5. As the shift bar clears the actuating plunger 1. If previously removed, install the reverse stop
boss, remove the actuating plunger, spring and plunger in the reverse yoke. Ensure that the
retaining cup. plunger is fully seated in the bore.
Note: These parts are not fitted on SAMT
transmissions.

6. If necessary support the reverse yoke in the vice 2. Install the spring in the bore and on the plunger.
and remove the reverse stop plunger plug.
Caution: The plug is under spring pressure.
Note: Plunger and spring are not fitted in the
SAMT transmission.

3/6 5/01
Shifting Controls

3. Install the plug. Tighten the plug until flush with 5. Push down the actuating plunger and install the
the yoke then unscrew 1 to 1 1/2 turns. Stake the reverse gear shift bar and yoke. Tighten the
plug threads through the hole in the yoke to lockscrew to the correct torque and lockwire to
secure. secure.

4. Mount the shift bar housing in the vice, rear end 6. Install one of the interlock balls in the housing
of the housing to the right i.e. the opposite way to bore. Ensure that the reverse shift bar is in the
disassembly. Install the neutral switch actuating neutral position and that the ball is resting in the
plunger, spring and spring retaining cup. neutral notch in the bar.

3/7 5/01
Shifting Controls

7. Insert the 1st/2nd gear shift block and shift bar 9. Install the second interlock ball.
into the housing. Insert the shift bar from the right.
Install the yoke on the bar, larger offset to the left.

8. Insert the interlock pin into the bar using grease 10. Install the 3rd/4th gear shift bar and block.
to hold it in place, and push the bar through until Install the yoke, longer offset to the right. Tighten
the yoke lockscrew can be installed. Tighten the the lockscrews to the correct torque and lockwire
lockscrew to the correct torque and lockwire to to secure. Check to ensure interlock only allows
secure. Slide the yoke and bar to the neutral one shift yoke to move at a time and remove the
position and install the block lockscrew. Tighten to housing from the vice.
the correct torque and lockwire to secure.

3/8 5/01
Shifting Controls

11. Install the three detent balls into the shift bar 13. Install the retaining capscrews and lifting eyes.
housing bores. Note the position of the lifting eyes and the
corresponding longer capscrews. Note: It is
essential that the long capscrews are installed in
the correct positions or they may otherwise jam on
the countershaft gear teeth. Tighten the capscrews
to the correct torque.

12. Ensure the sliding clutches and the shift yokes 14. Ensure all the shift bars are in neutral and
are in the neutral position and install the shift bar install the three detent springs in the bores.
housing and gasket on to the main transmission
housing.

3/9 5/01
Section 4 Main Transmission

5/01
Main Transmission
A. Removal/Disassembly of Auxiliary Section
Caution: Drain Gear Oil
Note: The overdrive auxiliary section is shown in the following steps. The procedure is the same for the
direct version except that the actual gear sizes in respect to the number of teeth on each gear will differ
from these illustrated. In order to avoid confusion between the functions of any particular gear in the
auxiliary section of either model, i.e. high/low/intermediate/overdrive, the splitter gears installed on the
main shaft will be referred to by their relative positions, not their functions.

1. Remove the shift bar housing assembly. 3. Disconnect the air hose from the splitter valve
Remove the lockwire and lockscrew from the and remove the regulator and hose.
splitter yoke.
Caution: Take care not to allow the lockscrew to
drop into the case

2. Insert two wooden wedges between the reverse 4. Remove the speedometer drive pinion. Engage
gear and the housing webs. This is to prevent the two gears in the main transmission and low (if not
mainshaft moving backward allowing the front already engaged) in the auxiliary section. Slacken
thrust race pack to be dislodged. but do not remove the flange securing nut.
Note: On SAMT transmissions, the speed
transducers must be removed from the
transmission case.
4/1 5/01
Main Transmission

5. Remove the lower (right-hand) auxiliary 8. Remove the snap ring from the bearings.
countershaft rear bearing cover. Remove the upper Remove both bearings using the special puller
(left-hand) auxiliary countershaft rear bearing engaged into the snap ring groove.
cover/PTO cover. Remove the snap rings from the
rear of both auxiliary countershafts.

6. Remove the bearing spacers from the rear of 9. Remove the auxiliary housing retaining bolts
both auxiliary countershafts. (Note the positions of the two longer bolts). Using
three M10 x 37mm bolts into the three threaded
holes as pullers, jack the auxiliary housing away
from the main case.

7. Using a suitable lever, prise both auxiliary 10. Attach the special lifting bracket and using a
countershafts rearward to expose the snap rings on hoist remove the auxiliary housing.
the two rear bearings.
Note: Guide the centre gear cluster yoke off the
selector bar as the housing is removed.

4/2 5/01
Main Transmission

11. Remove the mainshaft rear thrust bearing pack 14. Push the centre gear cluster forward and
(one standard washer, one thrust race and one remove the centre jaw clutch.
graded washer OR one vespel washer and one
graded washer) from the mainshaft rear spigot.

12. Using the jaw clutch spring compressor remove 15. Remove the centre gear cluster selector yoke.
the snap ring from the rear of the mainshaft.

13. Remove the rear jaw clutch and spring from

the mainshaft.

4/3 5/01
Main Transmission

16. Slide the centre gear cluster rearward again 18. Lift out the lower (right-hand) auxiliary
approximately 25mm. Slide the upper (left-hand) countershaft. Remove the support rod. Slide out
auxiliary countershaft rearward approximately the upper (left-hand) auxiliary countershaft.
12mm. Remove the snap ring from the mainshaft.
Lay a 20mm diameter rod (arrowed) under the
lower (right-hand) auxiliary countershaft and push
it into the hole in the casing web. Slide the
auxiliary countershaft rearward until clear of its
front bearing and support it on the rod.

17. Carefully manoeuvre the centre gear cluster 19. Using the jaw clutch spring compressor tool,
out between the teeth of the two auxiliary compress the spring and remove the front jaw
countershafts and remove it from the housing. clutch retaining snap ring. Remove the jaw clutch,
spring and spring retainer.
Note: A snap ring on the mainshaft will restrict the
gear cluster from sliding along it easily during
removal.

4/4 5/01
Main Transmission
B. Removal and Disassembly of the Output shaft and Auxiliary Section Rear
Sliding Gear

1. Bush 8. Outer bearing cone and rollers

2. Output shaft 9. Speedometer drive gear
3. Inner bearing cup 10. Grit shield
4. Inner bearing cone and rollers 11. Output drive flange
5. Inner spacer 12. Flange retaining nut
6. Outer spacer 13. O-ring
7. Outer bearing cup

1. Remove the lockwire and lockscrew from the 2. Remove the splitter valve and actuating cylinder
lower selector yoke. Withdraw the yoke and the taking care not to damage the mating faces.
rear sliding gear from the output shaft. Protect valve and cylinder from dirt, grease and oil.

4/5 5/01
Main Transmission

3. Remove the flange retaining nut, lift off the 6. Remove the two taper roller bearing cups and
flange and grit shield. Remove the cap screws the outer spacer from the auxiliary housing.
securing the oil seal and pinion housing. Note the
position of the two special bolts. Lift off the
housing. If necessary drift out the oil seal

4. Lift off the speedometer drive gear. 7. Using the auxiliary rear sliding gear as a
support, press the output shaft through the bearing
cone and roller assembly.

5. Press or drift out the output shaft 8. Remove the spigot bush from the output shaft
using a suitable internal extractor.

4/6 5/01
Main Transmission
C. Auxiliary Countershaft Bearing D. Auxiliary Section Splitter Gears
Renewal and Sensor Disassembly

Note: The three sensors, one in each of the three

splitter sliding gears are identical in all respects.
Unless they are all to be renewed it is essential
that each assembly is kept separate for
reinstallation in the same sliding gear from which it
was removed.
Note: The centre sliding gear clusters consist of
two separate gears which are assembled together
in production. They cannot be separated in service.

1. When fitted, remove the snap ring and remove

the bearing tracks using a suitable puller. If a snap
ring groove is not provided on the front end of the
shaft, the bearing track is retained with Loctite.
Carefully heat the bearing track if necessary to
deactivate the Loctite.

1. Using suitable circlip pliers remove the sensor

retaining snap ring. Lift out the sensor. (Centre
gear cluster illustrated).

2. Apply a thin bead of Loctite 601 to the auxiliary

countershaft front bearing spigot. (On shafts with a
circlip groove machined on the front bearing spigot,
the snap ring may be omitted if Loctite is used.)

3. Heat the new front bearing inner track to a

maximum of 135°C and place it on the auxiliary
countershaft, shouldered side towards the gears. 2. Remove the energiser ring from the sensor
using angled grips or pliers

4/7 5/01
Main Transmission
E. Splitter Gears Reassembly
Splitter Sliding Gears and Jaw Clutches - Exploded View.

1. Spring retainer 12. Jaw clutch

2. Spring (short) 13. Sensor
3. Jaw clutch 14. Yoke
4. Energiser ring 15. Rear sliding gear
5. Sensor 16. Mainshaft snap ring
6. Yoke
7. Centre sliding gear
8. Sensor
9. Retaining snap ring
10. Jaw clutch
11. Spring (long)

1. Mount the sensor in the vice as illustrated. Insert 2. Place the sensor in the sliding gear (centre gear
the new energiser ring into the groove, overlapping cluster illustrated) and fit the retaining snap ring.
part at the bottom. Using two screwdrivers expand
the ring until the ends abut and snap into the
groove.

4/8 5/01
Main Transmission
F. Rear Sliding Gear and Output Shaft
Reassembly and Installation

1. Support the shaft and using a suitable installer 3. Heat both output shaft bearing inner cones and
and mallet drive in the new bush until fully home roller assemblies to a maximum of 135°C before
against the shoulder. installation. Install the (heated) front bearing cone
and roller assembly on to the shaft against the
splined flange. Install the inner spacer against the
bearing.

2. The output shaft bearing and spacers are a 4. Stand the output shaft, with the assembled
matched set. All six items are etched with a serial bearing on a wood block approximately 50mm
number (i.e. 84/21994). Both parts of one of the thick. Place the housing over the shaft.
bearings are marked with the suffix A. It is
essential that these parts are assembled together,
and that all parts carry the same serial number

4/9 5/01
Main Transmission

5. Drive the outer cup of the inner bearing conical 7. If previously removed install a new oil seal, flat
face downwards into the auxiliary housing. Install face uppermost, into the speedometer housing.
the outer spacer with the lubricating oil hole
aligned with the hole in the housing bore, and the
outer bearing cup, shoulder uppermost, on the
inner bearing cup. Drive all three parts into the
housing bore.

6. Install the (heated) outer bearing inner cone and 8. Place the speedometer drive gear over the
roller assembly over the shaft against the spacer. output shaft. (If a speedometer drive gear is not
Make sure that the outer bearing cup shoulder fitted, a spacer of equivalent thickness must be
abuts the housing and the bearing fits closely. installed.)

4/10 5/01
Main Transmission

9. Place the speedometer housing and gasket on 11. Locate the plastic grit shield on to the output
the auxiliary housing, and insert the speedometer drive flange, dished face away from the flange. Do
pinion into the housing. Ensure that speedometer not push fully on to the flange. Install the flange
housing is correctly positioned. and grit shield onto the output shaft.

10. Install the capscrew and tighten to correct 12. Install a new self-locking nut and tighten to the
torque. correct torque. Rotate the shaft as the nut is
tightened to ensure that the bearings are correctly
Note: Install the capscrew adjacent to the
seated. Finally ensure that the nut is adequately
speedometer pinion with a new nylon washer.
staked into the output shaft groove.

4/11 5/01
Main Transmission

13. Put timing marks on the rear sliding gear (in

16. Install the rear sliding gear on to the output
preparation for installation of rear housing to main
shaft, sensor facing forward. Install the selector
case). Paint any two adjacent teeth and then the
yoke into the groove in the sliding gear and onto
two teeth directly opposite the first two.
the lower selector piston bar.

14. Place the selector cylinder into the rear of the

auxiliary housing.
17. Install the lockscrew and tighten to the correct
torque. Lockwire to secure.

15. Secure the selector cylinder together with the

splitter valve, using new gaskets, to the rear of the
housing. Tighten the capscrews to the correct
torque.

4/12 5/01
Main Transmission
G. Main Section Disassembly

1. Remove the input shaft cover. Note the position 4. Remove the snap rings from the front of both
of the two capscrews with drilled heads. (Push countershafts.
type clutch release bearing only).

2. Grasp the input shaft firmly and joggle the shaft, 5. Remove the snap rings from the rear of both
gear and bearing out of the housing. Retain the countershafts.
parts in order for the reassembly.

3. Remove the mainshaft thrust washers and the 6. Using a pry bar remove the two auxiliary
3rd/4th gear sliding clutch from the mainshaft. countershaft front bearings from the housing.

4/13 5/01
Main Transmission

7. Remove the left-hand (upper) reverse idler gear 10. Remove the reverse gear retaining snap ring
shaft support washer. from the mainshaft. Remove the plain spacer and
the large internally splined spacer.

8. Tap the idler gear shaft forwards approximately 11. Remove the wedges and slide the reverse gear
10mm and remove the circlip from the front end of rearward on the shaft. Using a probe push the
the shaft. internal spacer in the gear forward and carefully
prise out the snap ring.

9. Using a slide hammer screwed into the rear of 12. Slide the reverse gear forward onto the reverse
the shaft, withdraw the shaft. Roll the reverse idler sliding clutch and against 1st gear. Remove the
gear away from the mainshaft (the washer will drop spacer and the graded washer.
into the case).

4/14 5/01
Main Transmission

13. Slide the complete mainshaft rearwards in the

16. Using the special puller remove rear bearing
housing. Using a soft drift and heavy mallet drive
from the countershaft.
the right-hand (upper) countershaft rearward
approximately 5mm (max) through the front
bearing. Drive the countershaft forward again, from
the rear, to expose the snap ring around the front
bearing.

17. Using suitable wooden blocks in the front and

rear bearing bores block the countershaft away
14. Remove the snap ring and assemble the
from the mainshaft.
special puller into the snap ring groove. Remove
the bearing from the shaft and housing.

15. Using a soft faced mallet drive the countershaft 18. Lift the mainshaft assembly from the housing.
rearwards again until the rear bearing is clear of its
bore in the housing.
4/15 5/01
Main Transmission

19. Remove the reverse idler gear and the idler 22. Remove the right-hand (lower) reverse idler
gear washer from the housing. gear support washer, shaft washer and idler gear
from the housing in the same manner as described
in operations 7 to 9 and 19 inclusive for the left-
hand idler gear.

20. Remove the upper (right-hand) countershaft

from the housing.
23. Remove the upshift brake from the bottom of
the housing.

21. Remove the bearings from the lower (left-hand)

countershaft in the same manner as described in
operations 13 to 16 inclusive for the upper
countershaft, and remove the countershaft from
the housing.

4/16 5/01
Main Transmission
H. Input Shaft Disassembly I. Input Shaft Reassembly

1. Bearing snap ring

2. Bearing
3. Spacer
4. Gear snap ring
5. Input gear
6. Input shaft
7. Spigot bush Input Shaft Assembly
1. Check the input shaft spigot bush, renew if
necessary..

1. Support the gear, remove the snap ring from the 2. Check the input gear snap ring, renew if
shaft and push or drive the shaft through the gear necessary. Install the input shaft into the drive gear
and off the bearing. Remove the spacer. against the snap ring.

4/17 5/01
Main Transmission

3. Place the 3rd/4th gear sliding clutch into the 5. Fit the snap ring.
drive gear against the end of the input shaft and
stand the assembly on the sliding clutch on the
bench. Fit the spacer over the input shaft.

4. Drive the bearing, shrouded face uppermost 6. Paint timing marks on any two adjacent gear
onto the shaft using a suitable driver. teeth on the input gear. Then paint two gear teeth
exactly opposite the first two.

4/18 5/01
Main Transmission
J. Reverse Idler Gear Disassembly
and Reassembly

4. Bearing
5. Reverse idler gear
1. Circlip 6. Idler gear shaft
2. Washer 7. Support washer
3. Sleeve 8. Capscrew

Reverse Idler Gear Assembly

1. Support the gear and press or drive out the

needle roller bearing using a suitable mandrel.
Support the gear and press or drive in the new
bearing until flush with the gear face.

4/19 5/01
Main Transmission
K. Mainshaft Disassembly

Serial Numbers: upto and including N 535711 (ERF), upto and including N 537124 (all other models).

A. Main Section B. Auxiliary Section

1. Sliding clutch 11. Main shaft 23. Retaining snap ring
2. Circlip 12. Sliding clutch 1st/2nd speed gear 24. Energiser ring
3. Graded washer - 3rd gear 13. Mainshaft snap ring 25. Sensor
4. Spacer 14. Graded washer 26. Auxiliary sliding gear centre cluster
5. Snap ring 15. 1st speed gear 27. Shift yoke
6. 3rd speed gear 16. Plain washer 28. Jaw clutch spring - long
7. 2nd speed gear 17. Reverse gear sliding clutch 29. Auxiliary sliding gear - rear
8. Snap ring 18. Reverse gear 30. Shift yoke
9. Spacer 19. Spacer ring 31. Graded thrust washer
10. Thrust race pack 20. Spring retainer plate 32 Thrust washer
a Standard washer 21. Jaw clutch spring - short
b Needle roller thrust race 22. Jaw clutch
c Graded washer

4/20 5/01
Main Transmission
K. Mainshaft Disassembly

Serial Numbers: upto and including N 535711 (ERF), upto and including N 537124 (all other models).

1. Support the mainshaft assembly in the vice, 3. Invert the mainshaft in the vice and remove the
forward end downwards and lift off the reverse 3rd speed gear circlip, spacer, washer and 3rd
gear. speed gear.

2. Remove the following in order: Snap ring, 4. Lift off the 2nd speed gear and remove the 2nd
reverse gear sliding clutch, 1st speed (rear) snap gear stepped spacer. If necessary remove the
ring and the large internally splined washer. internal snap rings from 1st, 2nd, 3rd and reverse
Remove the 1st speed gear, the externally splined gears.
spacer and the internally aplined graded washer.
Remove the snap ring and the 1st/2nd gear sliding
clutch.

4/21 5/01
Main Transmission
K. Mainshaft Disassembly

Serial Numbers: N 535712 and above (ERF); N 537125 and above (all other models).

A. Main Section B. Auxiliary Section

1. Sliding clutch 11. Main shaft 23. Retaining snap ring

2. Snap ring 12. Sliding clutch 1st/2nd speed gear 24. Energiser ring
3. Graded washer - 3rd gear 13. Mainshaft snap ring 25. Sensor
4. Spacer 14. Graded washer 26. Auxiliary sliding gear centre cluster
5. Snap ring 15. 1st speed gear 27. Shift yoke
6. 3rd speed gear 16. Plain washer 28. Jaw clutch spring - long
7. 2nd speed gear 17. Reverse gear sliding clutch 29. Auxiliary sliding gear - rear
8. 2nd/3rd gear spacer 18. Reverse gear 30. Shift yoke
9. 2nd gear spacer 19. Spacer ring 31. Graded thrust washer
10. Thrust race pack 20. Spring retainer plate 32. Thrust washer
a Standard washer 21. Jaw clutch spring - short
b Needle roller thrust race 22. Jaw clutch
c Graded washer

4/22 5/01
Main Transmission
K. Mainshaft Disassembly

Serial Numbers: N 535712 and above (ERF); N 537125 and above (all other models).

1. Support the mainshaft assembly in the vice, 3. Invert the mainshaft in the vice and remove the
forward end downwards and lift off the reverse snap ring, graded spacer and 3rd gear assembly.
gear.

2. Remove the following in order: Snap ring, 4. Using a suitable puller or press remove the 2nd
reverse gear sliding clutch, 1st speed (rear) snap gear assembly and 2nd/3rd gear mainshaft spacer.
ring and the large internally splined washer.
Remove the 1st speed gear, the externally splined
spacer and the internally splined graded washer.
Remove the snap ring and the 1st/2nd gear sliding
clutch.

4/23 5/01
Main Transmission
L. Determine and Adjust Mainshaft
End Float

1. Using a new gasket, position the auxiliary

housing, complete with fully assembled output
shaft, onto the rear of the main housing. Secure
with at least 6 capscrews. Tighten to the correct
torque. Assemble onto the mainshaft front end
5. The second gear spacer, again using a suitable spigot one thrust race pack consisting of one
puller or press can now be removed from the standard thickness steel washer and one vespel
mainshaft. thrust washer, the steel washer against the shaft.
Retain inplace with petroleum jelly.

2. Assemble onto the mainshaft rear spigot a thrust

race pack consisting of one thrust race with one
standard thickness washer and one graded
6. If necessary the snap ring and splined spacer thickness washer. Alternatively, one graded
can be removed from the 2nd and 3rd gears. thickness steel washer and one vespel thrust
washer may be used. Use the thinnest available
new graded washer. Retain with petroleum jelly.
Position the mainshaft and install the input shaft
and cover using a new gasket. Secure with at least
3 capscrews tighten to the correct torque.

4/24 5/01
Main Transmission

5. Remove the input shaft and mainshaft. If

necessary reassemble with the new size graded
washer rearmost on the rear spigot and recheck
the end float as before. Remove the input shaft,
mainshaft and rear housing. Retain the thrust race
packs in their order for installation later.

3. Position a dial gauge and magnetic base in the

housing with the plunger against the shoulder on
the mainshaft. Push both the input shaft and
mainshaft rearwards and zero the gauge.

4. Hold the input shaft and push the mainshaft

forward and note the end float reading. If the end
float is outside the specified limits, 0,13 - 0,71mm,
a thicker or thinner graded washer must be
selected to replace the existing graded washer on
the rear spigot of the mainshaft.
Washers are available in the following
thicknesses/colour codes.
White 1,52 to 1,60mm
Green 1,84 to 1,92mm
Orange 2,16 to 2,44mm
Purple 2,48 to 2,56mm
Black 2,80 to 2,88mm
Yellow 3,12 to 3,20mm

4/25 5/01
Main Transmission
M. Mainshaft Reassembly (Main
Section)
Serial Numbers upto and including N 535711
(ERF), upto and including N 537124 (all other
models).
Mainshaft Gears - Axial Clearances
The axial clearances for mainshaft gears are:
Reverse/Forward speed gears - 0,13-0,30mm
Graded washers are used to obtain the clearances
within the correct limits; six different thicknesses
are available as follows:

Thickness Colour Code

6,30 - 6,35mm White
6,43 - 6,48mm Green
6,55 - 6,60mm Orange
6,68 - 6,73mm Purple
6,80 - 6,86mm Yellow 2. Support the mainshaft in a soft jawed vice,
6,93 - 6,99mm Black forward end uppermost. Place the shouldered
spacer on the mainshaft, shoulder downwards.

Refer to Illustrated Parts List for part numbers.

Note: During reassembly of the mainshaft it is
essential to ensure the correct part numbers are
used in the correct locations. (All major
components have their part number stamped into
them.)

1. If removed, install new snap rings into the 1st,

2nd, 3rd and reverse speed gears. 3. Install the 2nd speed gear over the washer,
clutching teeth downward.

4/26 5/01
Main Transmission

4. Place the 3rd speed gear over the shaft against 6. Install the graded washer into the 3rd speed
the 2nd speed gear, clutching teeth uppermost. gear, chamfered face uppermost.

5. Install the spacer into the 3rd speed gear. 7. Install the 3rd speed gear reatining circlip.

4/27 5/01
Main Transmission

8. Check the clearance between 2nd and 3rd

gears using two sets of feeler gauges. If the
clearance is not within the correct limits the graded
washer should be removed again and a thicker or
thinner graded washer installed as required in its
place.
10. Install the 1st speed gear snap ring into its
groove in the mainshaft.

9. Invert the shaft and gears in the vice and install 11. Place a graded washer over the shaft,
the 1st/2nd gear sliding clutch. chamfered face against the snap ring.

4/28 5/01
Main Transmission
M. Mainshaft Reassembly (Main
Section)
Serial Numbers: N 535712 and above (ERF); N
537125 and above (all other models).

Mainshaft Gears - Axial Clearances

The axial clearances for mainshaft gears are:
Reverse/Forward speed gears - 0,13-0,30mm
Graded washers are used to obtain the clearances
within the correct limits; six different thicknesses
are available as follows:

Thickness Colour Code

6,30 - 6,35mm White
2. Check the 2nd and 3rd gear splined spacers for
6,43 - 6,48mm Green wear and if still acceptable refit them into the gears
6,55 - 6,60mm Orange along with new snap rings.
6,68 - 6,73mm Purple
6,80 - 6,86mm Yellow
6,93 - 6,99mm Black

Refer to Illustrated Parts List for part numbers.

Note: During reassembly of the the mainshaft it is
essential to ensure the correct part numbers are
used in the correct locations. (All major
components have their part number stamped into
them.)

3. Press the 2nd gear spacer onto the mainshaft

and then fit the 2nd gear assembly clutching teeth
down.

1. If removed, install new snap rings into the 1st

and reverse speed gears

4/29 5/01
Main Transmission

4. Press the 2nd/3rd gear spacer onto the shaft. 6. Remove the chosen graded mainshaft washer.

5. From the range of graded mainshaft washers 7. Fit the 3rd gear assembly clutching teeth up,
select one which allows the least amount of selected graded mainshaft washer and snap ring.
clearance between the snap ring and the 2nd/3rd
gear spacer.

4/30 5/01
Main Transmission

8. The 2nd/3rd gear mainshaft clearance should 10. Install the 1st speed gear snap ring into its
now be set. groove in the mainshaft.

9. Invert the shaft and gears in the vice and install 11. Place a graded washer over the shaft,
the 1st/2nd gear sliding clutch. chamfered face against the snap ring.

4/31 5/01
Main Transmission

12. Place a spacer over the shaft, flat (mating) face 14. Fit the plain washer against the 1st speed gear.
against the graded washer.

13. Install the 1st speed gear on the shaft and over 15. Install the 1st speed gear retaining snap ring.
the spacer, clutching teeth downwards towards the
sliding clutch.

4/32 5/01
Main Transmission

16. Check the clearance between 1st speed gear 18. Install the reverse gear front snap ring into the
and the washer using two sets of feeler gauges. If groove in the mainshaft.
the clearance is not within the correct limits the
graded washer should be removed again and a
thicker or thinner graded washer installed as
required in its place.

19. Place the reverse gear graded washer over the

shaft, chamfered face downwards against the snap
17. Install the reverse gear sliding clutch, longer, ring.
clutching teeth uppermost.

4/33 5/01
Main Transmission

20. Install the spacer, flat (mating) face against the 22. Fit the flat washer against the reverse gear and
graded washer. the spacer ring against the flat washer.

21. Install the reverse gear over the spacer, 23. Install the reverse gear retaining rear snap
clutching teeth downwards towards the sliding ring.
clutch.

4/34 5/01
Main Transmission

24. Install the spring retainer plate and the short 26. Check the clearance between the reverse gear
jaw clutch spring onto the mainshaft. and the flat washer using two sets of feeler
gauges. If the clearance is not within the correct
limits the graded washer must be removed again
and a thicker or thinner graded washer installed as
required in its place. Remove the assembly from
the vice.

25. Locate the jaw clutch on the mainshaft; using

the special tool E113 compress the spring and
install the retaining snap ring.

4/35 5/01
Main Transmission

N. Main Transmission Reassembly

1. Before starting reassembly, make sure the two 3. Install the bearing sleeve into the right-hand
magnetic discs are cleaned of swarf and are (lower) reverse idler gear/bearing.
securely adhering to the floor of the housing. Note: Both gears are identical. When using the
original gears assemble the gears back in the
same position from which they were removed in
order to maintain wear patterns.

2. The gears on the two countershafts are 4. Position the reverse idler gear, counterbored
identical. The lower (left-hand) countershaft has an face rearmost, into the housing with the washer
extended shaft for a power take off. located forward of the gear against the support.
A. Upper (right-hand) countershaft Insert the idler gear shaft through the bearing
sleeve and washer into the housing using a little
B. Lower (left-hand) countershaft petroleum jelly to assist retention of the washer.

4/36 5/01
Main Transmission

5. Drive the shaft into the housing until the circlip 7. Paint timing marks on the drive gear and on the
groove is accessible and install the circlip. Pull or two countershafts. On the drive gear, if not already
drive the shaft rearward again (gently) until the marked, paint any two adjacent teeth. Then paint
circlip abuts the housing. the two teeth directly opposite the first two.

6. Rotate the shaft to align the slot with the oil hole 8. On each countershaft, the front (drive) gear is
in the housing. Apply sealer to the capscrew marked on its rear race with an 'O' by one of the
threads and install the support washer. Do not teeth. Paint this tooth on each gear. Illustration
overtighten. shows the three gears (disassembled) correctly
marked.

4/37 5/01
Main Transmission

9. Locate the lower (left-hand) countershaft 11. Using a suitable flanged installer drive the
(extended shaft) into the housing centralising it in bearing onto the shaft and into the housing. Fit the
the bearing bores. retaining snap ring on the shaft.

10. Locate the countershaft rear bearing over the 12. Locate the countershaft front bearing on the
shaft and into the housing. shaft, snap ring groove outermost and using a
suitable flanged installer, drive the bearing onto the
Note: The inner track of the bearing is radiused on
shaft and into the housing.
one face and chamfered on the other. The
radiused face must be toward the front, chamfer to
the rear.

4/38 5/01
Main Transmission

13. Install the bearing retaining snap ring on the 15. Place the upper (left-hand) reverse idler gear
shaft. Rotate the shaft to bring the timing mark in into position, counterbored face to the rear, resting
line with the mainshaft bores. it in mesh with the countershaft and against the left
side of the case.

14. Place the upper (right-hand) countershaft in the 16. Place the assembled mainshaft into the
housing. Use wooden blocks in the bearing bores housing (rear end first).
to support the countershaft as far to the right-hand
side as possible and align the timing marks to face
the lower countershaft.

4/39 5/01
Main Transmission

17. Locate the mainshaft approximately in position 19. Place the 3rd/4th gear sliding clutch into the
and in mesh with the lower countershaft and end of the assembled input shaft. Align the timing
support at the rear on a suitable wood block. marks on the input shaft with the lower (left-hand)
countershaft and install the input shaft, taking care
not to dislodge the thrust race pack.
Note: Note the different sizes of clutching teeth on
Serial Numbers N 535712 and above (ERF), N
537125 and above (all other models).

18. Place the mainshaft front thrust race pack onto

the mainshaft front spigot, steel washer against the
shaft. Retain in place with petroleum jelly. 20. Push the input shaft fully home and install the
input shaft cover. Note the correct position of the
drilled capscrews, when fitted. Tighten to the
correct torque. Insert two wedges between reverse
gear and the housing to prevent the mainshaft
sliding rearwards.
Check to ensure that the countershaft is still
correctly timed to the input shaft.

4/40 5/01
Main Transmission

21. Rotate the upper (right-hand) countershaft as 23. Remove the dummy support from the rear of
necessary to align the timing marks with the input the upper (right-hand) countershaft and install the
shaft, engage the gear teeth and support the rear bearing as described in sub-operations 10 and
countershaft in position with a dummy support tool. 11 ensuring that the radiused face of the inner
track is toward the front, chamfer to the rear. Fit
the snap ring.

22. Partially install the countershaft front bearing 24. Raise the rear of the mainshaft slightly and roll
and check the timing marks are aligned correctly. the upper reverse idler gear into mesh with the
Using a suitable flanged installer drive the reverse gear. Grease one side of the thrust washer
countershaft front bearing onto the shaft and into and insert it between the front face of the gear and
the housing. Fit the snap ring. the housing. Insert the idler gear shaft into the
housing.

4/41 5/01
Main Transmission Main Transmission
O. Reassembly of Auxiliary Section

25. Drive the shaft into the housing until the circlip 1. Paint timing marks on both auxiliary
groove is accessible and install the circlip. Align countershafts. Paint along all three gear teeth on
the slot in the shaft with the oil hole in the housing, each countershaft in line with the 'O' stamped on
apply sealer to the capscrew threads and install the front gear..
the support washer.

26. Install the upper and lower auxiliary 2. On the forward sliding gear paint any two
countershaft front beaings, driving them into the adjacent teeth and then two teeth directly opposite
housing bores using a suitable flanged driver, until the first two. Paint highlighting marks on the sensor
they abut the two reverse idler gear support ring blocker teeth to aid alignment with the jaw
washers. clutches during assembly.

4/42 5/01
Main Transmission

3. Paint highlighting marks on the two teeth, one 5. Locate the jaw clutch on the mainshaft with the
each side of the master blocking spline on the jaw marked master spline uppermost. Using the
clutches, to aid alignment with the sensor ring special tool, compress the spring and install the
during assembly. front jaw clutch retaining snap ring on the
mainshaft.

4. Remove the support block and install the spring 6. Install the centre jaw clutch snap ring on the
retainer plate and the short jaw clutch spring on mainshaft. Install the upper (left-hand) auxiliary
the mainshaft. countershaft into its front bearing. Align the timing
marks toward the mainshaft.

4/43 5/01
Main Transmission

7. Place a 20 mm dia x 300 mm long bar in the 9. Install the sliding gear cluster onto the mainshaft
housing with the end located in the housing web. ensuring that:
Chamfer the end of the bar if necessary. a: blocker spline on front sensor is aligned with jaw
clutch.
b: timing mark on front sliding gear is correctly
meshed with upper (left-hand) countershaft timing
mark.

8. Lay the lower (right-hand) auxiliary countershaft 10. Install the jaw clutch for the rearmost gear of
on to the bar and against the side of the housing. the cluster into the sensor and against the snap
Align the timing marks towards the mainshaft. ring on the mainshaft.

4/44 5/01
Main Transmission

11. Place the longer jaw clutch spring on the 13. Install the sliding gear cluster yoke into the
mainshaft, place the rear jaw clutch against the cluster, offset boss towards the front.
spring. Using the special tool compress the spring
and install the rear snap ring onto the mainshaft.

12. Remove the bar supporting the lower (right- 14. Install the mainshaft rear thrust race pack (one
hand) auxiliary countershaft, align the timing marks standard washer, one thrust race and one graded
and install the countershaft into its front bearing. washer OR one graded washer and one vespel
Check to ensure the gears are correctly timed. thrust washer) onto the mainshaft rear spigot.
Retain in place with petroleum jelly.

4/45 5/01
Main Transmission

15. Install the gasket. Raise the auxiliary rear 18. Fit the remaining capscrews and tighten to the
housing using the lifting bracket and a hoist. correct torque. Note the correct positions of the
two longer capscrews.

16. Install the auxiliary housing to the main

housing ensuring that:
a. Timing marks align and engage
b. Jaw clutch aligns and engages
c. Yoke boss aligns with the piston operating bar
Remove the lifting bracket, push the housing fully
home and temporarily secure with two capscrews.

17. Carry out the following checks before

proceeding any further.
a. Engage one of the sliding clutches in the main
section and rotate the input shaft several times.
The main gear train should rotate without binding.
b. Rotate the output shaft flange. The auxiliary
gear train should rotate without binding.
c. Engage the sliding gear cluster on to one of the
jaw clutches and again rotate the input shaft. The
entire drive train through to the output shaft flange 19. Align the sliding gear yoke with the splitter
should rotate without binding. cylinder bar and install the lockscrew. Tighten to
d. If there is any binding either a jaw clutch is not the correct torque and lockwire to secure.
aligned or the auxiliary gear train is not correctly
timed.

4/46 5/01
Main Transmission

20. Using a suitable flanged driver drive the 22. Tighten the flange nut to correct torque. Stake
bearing into the housing. Similarly fit and install the the nut into the groove on the shaft.
upper auxiliary countershaft rear bearing.

21. Fit bearing outer spacers and the snaprings. 23. Install the bearing covers using new gaskets.
Tighten the capscrews to the correct torque.

4/47 5/01
Main Transmission

24. Install the pressure regulating valve and the air 26. Fit the shift bar housing capscrews and tighten
lines. Check the operation of the air system using to the correct torque. Note the position of the lifting
a dry, regulated air supply and ensure freedom eyes together with the longer bolts.
from leaks.

25. Ensure that all the sliding clutches and the shift 27. Install the remote control housing and gasket.
bar housing yokes are in neutral and install the Note the conical nuts, tighten to the correct torque,
shift bar housing, using a new gasket. then fit and tighten the lock nuts.

4/48 5/01
Main Transmission

28. Raise the transmission from the stand and

install the upshift brake using a new gasket. Fit the
capscrews and tighten to the correct torque. Check
backlash as described. Connect the air line to the
pulse unit.

4/49 5/01
Section 5 Changing the Input Shaft

5/01
Changing the Input Shaft

In some cases in service it may be necessary to

renew or replace the input shaft due either to wear
on the splines caused by the clutch or for reasons
of implementing a change in clutch type or clutch
hub diameter.
In these instances the input shaft can be renewed
without disassembling the transmission other than
the removal of the clutch housing and shift bar
housing, by carrying out the following detailed
procedure:

2. Remove the front bearing cover.

Note: There are two types of cover fitted
depending on whether a push or pull action clutch
release bearing is installed, Note the position of
the two special capscrews when a push action
clutch is fitted.

Input Shaft Disassembly

1. Remove the gear shift remote control housing 3. Grasp the input shaft firmly and joggle the shaft,
and shift bar housing from the transmission.t. gear and bearing out of the housing. Retain the
parts in order for reassembly.

5/1 5/01
Changing the Input Shaft

Input Shaft Reassembly

4. Remove the mainshaft thrust washers and the Input Shaft - Exploded View
3rd/4th gear sliding clutch from the mainshaft..
1. Bearing snap ring 5. Input gear
2. Bearing assembly 6. Input shaft
3. Spacer 7. Spigot bush
4. Gear snap ring

5. Support the gear, remove the bearing snap ring 1. Check the input gear snap ring, renew if
and press or drive the shaft through the gear and necessary.
off the bearing. Remove the spacer from the gear.

5/2 5/01
Changing the Input Shaft

2. Secure the input shaft in a vice and install the 4. Install the sliding clutch into the drive gear and
spigot bush using a suitable driver. stand the asembly on the bench on the sliding
clutch. Fit the spacer over the input shaft.

3. Assemble the new input shaft into the drive gear 5. Drive the bearing, shrouded face upward, onto
against the snap ring. the shaft using a suitable driver.

5/3 5/01
Changing the Input Shaft

6. Fit the snap ring. 8. Paint timing marks on any two adjacent gear
Note: The ends of the snap ring are angled slighty teeth on the drive gear and the two teeth exactly
to ease removal. Ensure snap ring is correctly opposite the first two.
fitted.

7. Locate the timing marks on the two countershaft 9. Place the mainshaft thrust race pack onto the
input drive gears (marked O) and paint the tooth at mainshaft spigot, steel thrust washer against the
both ends and along its length. shaft. Retain in place with petroleum jelly.

5/4 5/01
Changing the Input Shaft

10. Install the 3rd/4th sliding clutch into the input 12. Install the front bearing cover. When a push
shaft, align the timing marks and gently push the type clutch release is fitted the two capscrews with
input shaft and bearing into the transmission the drilled heads are fitted into the uppermost two
housing. Lift the mainshaft slightly to aid holes. Tighten the capscrews to the correct torque.
installation, Do not drift the shaft in or the thrust
race pack may be dislodged or damaged.

11. Ensure the timing marks are still aligned. 13. Reinstall the shift bar housing and remote
control housing.

5/5 5/01
Section 6 Upshift Brake

5/01
5/01
Upshift Brake
Serial Numbers upto and including N 533586.

Upshift Brake - Exploded View

1. Capscrew 6. Spacer 11. Compression spring 16. O-ring

2. Tab washer 7. Gear 12. Pressure plate 17. O-ring
3. Keep plate 8. Friction disc outer (3 off) 13. Piston 18. Gasket
4. Spacer 9. Friction disc inner (4 off) 14. O-ring 19. Housing
5. Bearing 10. Hub shaft 15. Piston support shaft

Upshift Brake - Sectional View

6/1 5/01
Upshift Brake
Upshift Brake Removal and
Disassembly

1. Disconnect the air hose from the upshift brake, 3. Straighten the tab washer. Remove the keep
drain the transmission oil and remove the upshift plate retaining screw and keep plate. Support the
brake. pressure plate and piston assembly.

2. Mount the assembly in a soft jawed vice and 4. Remove the piston return spring.
remove the elbow connector. Remove the two
countersunk head retaining screws. Remove the
piston support shaft.

6/2 5/01
Upshift Brake

5. Remove the pressure plate and piston 8. Remove the spacer rings and hub from the gear
assembly. and if the bearing is to be renewed, drive the
bearing out of the gear.

6. Lift out the gear, hub and brake disc assembly.

9. Separate the piston from the pressure plate.
Reassembly and Installation

7. Remove the lined and unlined brake discs from

the splined hub and gear.

6/3 5/01
Upshift Brake
Reassembly and Installation

1. Clean and examine all parts, renew as 3. Install the thinner spacer ring over the hub and
necessary. Renew all O rings. Use silicone install the hub and gear into the housing.
lubricant when assembling the O rings. If removed
install a new bearing with shield towards brake
plate into the gear using a suitable flanged driver.

2. Install the hub into the gear bearing, tapping the 4. Install the four lined and three unlined brake
hub lightly with a soft faced hammer if necessary, discs over the hub and into the gear in alternate
until fully home. sequence.
Note: The first and last plates will be lined plates
when correctly installed.
Note: SAMT transmissions only have three lined
and two unlined plates.

6/4 5/01
Upshift Brake

5. Ensure that the lined plates slide easily over the 7. Install the piston and pressure plate assembly,
splines on the hub and the unlined plates in the pressure plate against the top, lined, plate.
slots in the gear.

6. Install the spacer inside the gear. 8. Refit the piston support shaft and secure with
two new patch locked countersunk headed screws.
Tighten to the correct torque.
Note: Loctite sealer may be used where new
screws are not available.

6/5 5/01
Upshift Brake

9. Install the piston return spring and keep plate.

Fit a new patch lock capscrew, tab washer and
tighten to the correct torque. Ensure the assembly
rotates freely.
Note: Loctite sealer may be used where a new
patchlock capscrew is not available.

10. Using PTFE tape or suitable sealer, install the

air connection elbow to the upshift brake. Install
the upshift brake assembly to the transmission
housing using a new gasket. Tighten the
capscrews to the correct torque. Reconnect the air
feed from the pulse unit.

11. Check the backlash through the hole in the

bottom of the housing. The correct backlash is
0,15 to 0,45 mm . Fit a thicker or a thinner gasket
to increase of decrease the backlash if necessary.

6/6 5/01
Upshift Brake
Serial Numbers N 533587 and above.

Upshift Brake - Exploded View

1. Housing 7. Friction disc - inner 13. O-ring 19. O-ring

2. Splined shaft 8. Friction disc - outer 14. O-ring 20. Drain plug
3. Gear 9. O-ring 15. Shaft 21. Washer
4. Bearing 10. Spring 16. O-ring 22. Gasket
5. Spacer 11. Pressure plate 17. Bolt 23. Elbow
6. Bolt 12. Piston 18. Washer

Upshift Brake - Sectional View

6/7 5/01
Upshift Brake
Removal and Disassembly

1. Disconnect the air hose from the upshift brake, 3. Remove the bolt (note the washer and O-ring).
drain the transmission oil and remove the upshift Remove the piston support shaft.
brake.

2. Mount the assembly in a soft jawed vice and 4. Remove the pressure plate and piston
remove the elbow connector. assembly. Remove the spring.

6/8 5/01
Upshift Brake

5. Remove the four bolts securing the splined shaft 7. Remove the spacer ring and shaft from the gear
and lift out the gear, splined shaft and brake disc and if the bearing is to be renewed, drive the
assembly from the housing. bearing out of the gear.

6. Remove the lined and unlined brake discs from 8. Separate the piston from the pressure plate.
the splined shaft and gear.

6/9 5/01
Upshift Brake
Reassembly and Installation

1. Clean and examine all parts, renew as 3. Install the spacer ring over the shaft and install
necessary. Renew all O-rings. If removed install a the shaft and gear into the housing. Install the four
new bearing into the gear using a suitable flanged bolts and tighten to the correct torque (40 - 50
driver. Nm).

2. Install the shaft into the gear bearing, tapping 4. Install the four lined and three unlined brake
the shaft lightly with a soft faced hammer if discs over the shaft into the gear in alternate
necessary, until fully home. sequence.
Note: The first and last plates will be lined plates
when correctly installed.

6/10 5/01
Upshift Brake

7. Refit the piston support shaft and secure with

the appropriate bolt (not forgetting the O-ring and
washer). Tighten to the correct torque (46 - 60
Nm).

5. Ensure that the lined plates slide easily over the

splines on the shaft and the unlined plates in the
slots in the gear.

8. Using PTFE tape or suitable sealer, install the

air connection elbow to the upshift brake. Install
the upshift brake assembly to the transmission
housing using a new gasket. Tighten the socket
headed countersunk screws to the correct torque.
Reconnect the air feed from the pulse unit.

9. Check the backlash through the hole in the

bottom of the housing. The correct backlash is
6. Install the O-ring, spring and pressure plate 0.15 to 0.45 mm. If there is insufficient backlash
assembly, pressure plate against the top lined use multiple gaskets to obtain the correct amount.
plate.
Refit the drain plug and washer. Tighten to the
correct torque (41 - 47 Nm).

6/11 5/01
5/01
Section 7 PTO Installation

5/01
5/01
PTO Installation
Fitting Extended Countershaft

Countershaft Extension Assembly

1. Snap ring.
2. Adaptor coupling.
3. PTO extension shaft.
4. Bearing.
5. Adaptor ring.
6. Spacing sleeve.
7. Cover.

1. Remove left-hand coverplate (7 bolts).

7/1 5/01
PTO Installation
Assembly of Extended Countershaft

1. Insert the snap ring into the adaptor coupling. 3. Fit the bearing on to the shaft with the radius of
the inner bearing ring to the shaft collar.

2. Fit the adaptor coupling onto the rear of the left- 4. Fit the spacer sleeve.
hand countershaft.

7/2 5/01
PTO Installation

5. Insert the shaft assembly into the adaptor 7. Fit the cover. Tighten the three capscrews to the
coupling. Use a suitable soft drift against the correct torque.
bearing outer ring to drive it into the housing.
Additional screws as required supplied with PTO
kit.
Refer to PTO Fitting Instructions to fit PTO.

6. Fit the adaptor ring onto the bearing.

7/3 5/01