Service.

Self-Study Programme 205

6-speed manual gearbox 02M

Design and Function

 Adapting modern automobiles to meet the 6-speed manual gearbox 02 M is a new
rapidly growing demands on driving comfort, development. It is a compact gearbox with six
environmental compatibility and driving perfor- forward gears for A-platform vehicles with trans-
mance calls for advanced improvements in gear- versely mounted engine.
box technology. Adding more gears means
smoother running and enables the gearbox to be A compact 6-speed gearbox was realised by
adapted better to the characteristics of the using two output shafts and one input shaft. In
various engines; it also contributes indirectly to this booklet, we will explain to you the new gear-
reducing exhaust emissions by enabling torque box and the technology used.
to be utilised more effectively.

205_052

NEW Important
Note

The Self-Study Programme Please always refer to the relevant Service Literature
is not a Workshop Manual. for all inspection, adjustment and repair instructions.
Service Literature.
2
Contents

Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4

Gearbox mechanism. . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Installation angle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7

Design. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8

Power transfer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12

Cable-operated gearshift mechanism . . . . . . . . . . . . 14

Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20

Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22

Test your knowledge . . . . . . . . . . . . . . . . . . . . . . . . . . 24

3
 Introduction

How many gears does a car need?

There are many reasons for introducing gearbo- Depending on the engine type used, a distinction
xes with more than five forward gears. Most is drawn between two modes:
importantly, it is a way to match the gearbox and
the engine even better than before. A second - A sporty mode for engines with high power
major reason is that the gearbox can help make output to quickly transfer high input torque,
modern vehicles more environmentally friendly. - A comfortable mode for exceptionally smooth
running, which is achieved thanks to more
Why a 6-speed gearbox? balanced and even transfer of input torque.

6-speed gearboxes have the following advan-

tages over 5-speed gearboxes:

- More driving comfort (e.g. through

smoother running),
- Better environmental compatibility
(low fuel consumption = lower
exhaust emissions),
- Better torque utilisation
(the engine runs more in the “efficient torque”
band),
- 6-speed gearboxes allow engines with a high
power output to be driven sportily.

What engines will be equipped with this gear-

box in model year 1999?

- 1.9-ltr. 66kW TDI engine

- 1.9-ltr. 85kW TDI engine
- 1.9-ltr. 110kW TDI engine

- 1.8-ltr. 132kW 5V turbocharged engine

- 1.8-ltr. 165kW 5V turbocharged engine
- 2.3-ltr. 125kW V5/4V engine
- 2.8-ltr. 150kW VR6/4V engine

4
Specifications

- Gearbox designation: 02 M
- Forward gears: 6
- Reverse gears: 1
- Maximum input torque: 350 Nm
- Method of installation: Transverse mounting
- Gear oil: DEA DES-5080
- Weight: 48.5 kg (front-wheel drive)
68 kg with angle drive (four-wheel drive)

Ratios and layouts

We do not intend to present all the possible variants here, as this would be beyond the scope of this booklet.
Instead, we will explain the principle by which the gearbox ratio is calculated using two examples:

Engine
2.8-ltr. 150kW VR6 / 4V 1.9-ltr. 85kW TD
Ratio Overall ratio Ratio Overall ratio
1st gear/drive pinion set I 41 : 12 = 3.417 14.351 41 : 11 = 1 : 3.818 12.363
2nd gear/drive pinion set I 40 : 19 = 2.105 8.841 40 : 19 = 1 : 2.105 6.816
3rd gear/drive pinion set I 40 : 28= 1.429 6.002 39 : 29 = 1 : 1.345 4.360
4th gear/drive pinion set I 37 : 34 = 1.088 4.470 35 : 36 = 1 : 0.972 3.147
5th gear/drive pinion set II 34 : 31 = 1.097 3.640 32 : 33 = 1 : 0.970 2.537
6th gear/drive pinion set II 31 : 34 = 0.912 3.024 29 : 36 = 1 : 0.806 2.108
Reverse gear/drive pinion set II (30 : 12) * (23 : 14) = 4.107 13.620 (31 : 11) * (23 : 14) = 4.630 12.108
Ratio, drive pinion set I 63 : 15 = 4.200 68 : 21 = 3.238
Ratio, drive pinion set II 63 : 19 = 3.316 68 : 26 = 2.615
Mode sport comfort

For a gearbox with two output shafts, the overall For reverse gear, the ratio of the reverse shaft must
ratio comprises two factors: still be taken into consideration, so the ratio compri-
firstly, the ratio of the input shaft to the output shaft ses two values.
(you will find this value in the table under Ratio).
Secondly, the ratio between the output shaft and the The ratio for a particular gear multiplied by the
differential. ratio for a particular drive pinion set gives the
overall ratio for the gear. This value is printed in
bold in the table.

5
 Introduction

Gearbox versions
There are two different gearbox versions:

- The version for vehicles with front wheel drive

and
- the version for vehicles with four-wheel drive.

The 4-wheel-drive version of the gearbox has an

additional transfer case for driving both the front
and rear axles.

Transfer case for

four-wheel drive

205_001

6
 Gearbox mechanism

The installation angle

of the gearbox is dependent on the The term "installation angle" describes the angle
engine type being used. at which the bolt holes on the engine flange are
Two different installation positions are possible: offset to match the engine’s angle of tilt. The
gearbox itself is not tilted.
- tilted back by 15°
for 4-cylinder engines and
- tilted forward by 8°
for VR6 engines.

205_032 205_031
Direction of
travel 4-cylinder engine VR6 engine

7
 Gearbox mechanism

Design

In a conventional gearbox, an input shaft trans- For the so-called short gearbox, one of which is
fers drive force to an output shaft on which the manual gearbox 02 M, VW uses two output
various gears are positioned. The more gears shafts - on which the gears are arranged -
there are lined in row on such a drive shaft, the instead of one.
longer it will be. This reduces the installation length considerably.

Selector shaft

Output shaft 1

Input shaft

Output shaft 2

8
Manual gearbox 02 M has one input shaft and The gears are arranged on both output shafts as
the two output shafts, TW1 and TW2. follows:
- TW1: Forward gears 1 to 4
- TW2: 5th and 6th gear and reverse

The reverse gear comprises a reverse shaft with

two gears via which the direction of rotation is
reversed. (In the illustration below, the reverse
shaft is hidden by the input shaft.)

Transfer case
for four-wheel drive

Housing

205_009

9
 Gearbox mechanism

Design of input shaft

The gear wheels of the input shaft are designed

as fixed gears, i.e. they are permanently linked
to the input shaft.

Input shaft
with fixed gears

205_047

Design of output shafts TW1 and TW2

The gear wheels run in needle bearings and can The sliding gears of the output shaft are
rotate on the output shaft. This is why they are continuously in mesh with the matching fixed
also known as sliding gears. Only when the gears of the input shaft, i.e. the sliding gears also
appropriate gear has been selected is the sliding rotate continuously. As the sliding gears - with
gear connected to the fixed gear of the output the exception of the idler of the engaged gear -
shaft via a sliding sleeve and a synchromesh are not permanently linked to their output shaft,
body. they transfer no torque to the output shaft in this
state.

Sliding gears

Sliding sleeve with synchromesh body

Fixed gear to differential
Output shaft
TW2
with sliding gears

Input shaft
with fixed gears

Output shaft
TW1
with sliding gears

Fixed gear to differential

Sliding gears 205_048

10
Double gearing

Replacing the conventional output shaft with two To achieve different ratios, opposed sliding gears
shorter output shafts alone is not enough to have different diameters and therefore different
achieve a short, compact design. It is still neces- numbers of teeth.
sary to find a way to transfer torque to both out- Gears of the TW2 have a larger diameter than
put shafts without requiring more components. the gears of the TW1.
This results in a 25% speed differential
In the case of manual gearbox 02 M, this pro- between the output shafts.
blem is solved by means of double gearing. In a
double gearing arrangement, a fixed gear of the Manual gearbox 02 M has three
input shaft is linked to a sliding gear of TW1 and double gearings:
a sliding gear of TW2. In this way, two gears can
be driven by only one fixed gear on the input - Sliding gear wheel, 1st gear, on TW1 and
shaft. reverse shaft with the the input shaft (red),
- Sliding gear wheel, 4th gear, on TW1 and
sliding gear 6th gear on TW2 with the input
shaft (blue) and
- TW1 and TW2 with the
differential gear (green).

Differential gear

Output shaft 1

205_030B

Reverse shaft

Input shaft

Output shaft 2

205_030
11
 Gearbox mechanism

R
205_010 205_011

Power transfer

Since gearbox 02M has two output shafts, power

is either transferred via the one shaft or via the
other shaft to the differential, depending on what
gear is selected.

Taking the selection diagram for the sake of cla-

rity, the individual gears can be assigned to the
power transfers shown in the figure on the right.

205_012

12
205_013 205_015

205_014 205_016

13
 Cable-operated gearshift mechanism

The two selector cables of the cable-operated gearshift mechanism

establish the connection between the gear lever and gearbox 02 M.

Mechanism for transferring the

motion of the selector cables to the
selector shaft.

Selector cable

Gear selector cable

205_027

205_028

The two selector cables transmit the motions of

the gear lever to the gearbox selector shaft. The
mechanism shown above translates the move-
ment of the selector cables into a movement of
the selector shaft in the gearbox.

14
Gear lever

The position of the gears is in accordance with the VW standard, except that an extra gear
has been added to fill a previously unallocated space.

205_004

Shift motion

Selection motion

The gear lever can be moved in the direction of

205_029
the three spatial axes. The mechanism of the
gear lever splits the gearshift operation of the
driver.

- A part of the mechanism transfers the - The other part of the mechanism transfers
right/left motion of the gear lever to the the forward/reverse motion to the gear
selector cable. With this operation, the driver selector cable. With this operation, the driver
selects the gate to be selected. engages the desired gear.

15
 Cable-operated gearshift mechanism

Selecting a gear

In essence, gear selection consists of three com- We will explain to you the sequence of operati-
ponents of the selector mechanism and gearbox: ons when selecting a gear by means of three
examples.
● The gear lever mechanism translates the
driver's operations. For the sake of clarity, we will split the selection
● The selector cables transfer the operation sequence into
of the selector lever mechanism to the - operations outside the gearbox
gearbox selector shaft. and
● The selector shaft mechanism on the gearbox. - operations inside the gearbox
This mechanism selects and engages the gear
wheel of the gear selected.

Gear lever

Selector cable Ball joint

Mechanism for transfer-

ring the motions of the
Gear selector cable Interlock
cable pull to the selector
shaft.

205_050

Shift fork

Sliding sleeve with synchroniser ring

Selector shaft
Output shaft 1

Sliding sleeve with synchroniser ring

Output shaft 2

Shift fork

Shift finger
205_049

16
 Left/right motion of the gear lever

205_045 Gear lever

Selector cable

205_024

The gear lever mechanism transfers the right/

left motion of the gear lever to the selector
cable. The gearbox mechanism translates the
motion of the gear selector cable into an up/
down movement of the selector shaft.

In the gearbox, this up/down motion causes

the shift finger on the selector shaft to move
upwards or downwards. The shift finger for
the selected gear pair then reaches into the
cutout in the relevant shift fork.

Selector shaft

205_022

17
 Cable-operated gearshift mechanism

Forward and reverse motion of gear lever.

205_044 Gear lever

Gear selector cable

205_025

The forward and reverse motions of the gear lever is

transferred to the shift cable. The gearbox mechanism
translates the motion of the gear selector cable into a
rotational motion of the selector shaft.

In the gearbox, this rotational motion of the selector

shaft causes the shift finger which has engaged in the
cutout in the shift fork to move the shift fork and gear
change sleeve sideways.
The gear change sleeve links the gear wheel of the sel-
ected gear to the output shaft. The selected gear is
then selected.

Selector shaft

205_023

18
 Selecting reverse gear

Gear lever
205_046

205_026

Spring
Selecting reverse gear represents a special case,
Ball joint since an interlock must first be cancelled in order
to engage this gear.
Gear lever

Interlock 205_040

Press down the interlock against the force of the

spring and the gear lever will slide down through
the ball joint.

205_041

Only then can the interlock be cancelled in order

to engage reverse by moving the gear lever to
the left and forwards.

205_042

A spring pulls the gear lever back up.

205_043

19
 Service

Adjusting the cable-operated gearshift mechanism

The procedure for adjusting the cable-operated

gearshift mechanism has been simplified:

- Pull the spring at both ends of the cable pull

back.
- Fix the springs by a rotational motion with the
plastic nuts (arrows).

205_034

- Attached to the gearbox housing is an adju-

sting pin which fixes the selector shaft in a
predefined position. Move the selector shaft
by hand into the gate of first and second gear
and then press the adjusting pin into the
gearbox housing. The gearbox pin latches
home in this position and locates the selector
shaft.

205_036

205_020
Push in the setting pin

20
 - You still have to move the gear lever into
the first and second gear positions. In the
figure, you can see two guide holes: one on
the gear lever and one in the housing.

205_021

- To fix the gear lever in place, pass locating

pin T10027 through bore A into bore B when
they are exactly one above the other.

- Now you can let the springs on the selector

205_035 cables snap back into place. Detach the adju-
sting pin from the gearbox housing and pull
the locating pin T10027 back out.

Locating pin T10027

205_052

21
 Sensors

Gearbox 02 M is equipped with two sensors:

- Switch for the reversing lights F4

- Speedometer sender G22

Switch for reversing lights F4

The reversing light switch is activated when the

selector shaft engages the reverse gear. The
reversing light switch has a two-pin connector
and is arranged below the adjusting pin for the
selector mechanism.

Task

When engaging reverse, the electrical circuit to

the reversing lights is closed via this switch.

205_037

205_003

22
 Sensors

Speedometer sender G22

The speedometer sender is bolted to the gearbox

housing and scans a sender wheel on the diffe-
rential.

Task

It records the vehicle's road speed for the control

unit with display unit in the dash panel insert.

Effects of failure

If the sender fails, the speed limiter cuts in

earlier.

205_033

Electrical circuit

G22

205_051

23
 Test your knowledge

1. What are the advantages of a 6-speed gearbox?

a) greater smoothness
b) higher speed
c) better environmental compatibility

2. Why does the 02M have two output shafts?

3. How are the gears arranged on output shafts TW1 and TW2?
TW1:
TW2:

4. Show the power train for the 6th gear in the drawing.

205_017

5. Explain the concept of “double gearing”?

6. Arrange the following steps for setting the cable-operated gearshift mechanism in the correct order:
a) Press in the adjusting pin into the gearbox housing.
b) Let the springs on the both selector cables snap back into place.
c) Move the gear lever in the correct position and fix in place with a pin.
d) Pull the locating pin out of the gear lever.
e) Move the selector shaft into the adjustment position by hand.
f) Pull the spring back out of the selector cables.
g) Remove the adjusting pin from the gearbox housing.

Solution:

24
Notes

25
 Notes

26
27
Solutions:
1. a, c
2. Because installation length is saved by using two short output shafts in comparison with only one long
output shaft.
3. TW1: 1st, 2nd, 3rd and 4th gear
TW2: 5., 6th gear and reverse
4.
205_016
5. With double gearing, one gear of the input shaft is in mesh with both a gear of the first output
shaft and a gear of the second output shaft. However, only one gear is engaged at any given time.
6. f, e, a, c, b, g, d.
 205

For internal use only © VOLKSWAGEN AG, Wolfsburg

All rights reserved. Technical specifications subject to change without notice.
840.2810.24.20 Technical status: 09/98

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