Manual transmission

& transaxle

Manual transmission & transaxle

Course code: TR02

Student training manual

Suzuki Online Training
 Foreword Suzuki Technician curriculum
In this training manual, we will study the fundamental principles
of automotive transmissions, transaxle and the clutch. This This training manual is part of the Non Suzuki Technician to
course offers the fundamentals and must be used in Suzuki Technician curriculum. The curriculum consists of the
conjunction with Suzuki service manuals for product specific following modules:
information and specifications.
1. GE01 Suzuki Introduction
2. GE02 Electrical / Electronics
3. GE03 Diagnostics
4. EN02 Engine Mechanical part I
5. EN03 Engine Mechanical part II
6. EN04 Engine Mechanical part III
7. EN05 Engine Auxiliary systems
8. DS01 Driveshaft/Axle
9. DS02 Driveshaft/Axle - transfer case
Smart manuals
10. BR02 Brake control systems
Some sections of this training manual contain videos with 11. TR02 Manual transmission / transaxle
detailed information on the topics you are studying. If you are 12. CS02 Control system / body electrical
studying this training manual on a PC, look out for the “green 13. CS03 Communication / bus systems
play video” symbol on any photo or picture in this manual,
click on the green button to watch a video providing you with
You are currently studying TR02 Manual Transmission/transaxle.
detailed information on that topic. Note: Internet connection
This module consists of the following courses:
required.

• TR02 Manual transmission & transaxle

This document is intended solely for training purposes only.
• TR02 Practical Activities
All vehicle repairs and adjustments must be carried out
according to the procedures stipulated in current service
manuals and technical bulletins.

TR01 Manual transmission & transaxle 2

 Table of contents

Topic Page Topic Page

Manual transmission fundamentals 4 RW420 & A6B424 6MT overview 34

Overview 5 Transaxle components 35
Transmission functions 5 Overhaul 36
Structure and operation 6
Important points for disassembly 37
Power transmission 6
Checks of internal transmission parts 37
Neutral position 6
Gear change 7 Important points for assembly 39
Shift lever 10 Failure diagnosis 39
Transmission operation 11 Clutch 42
Synchromesh mechanism operation 12 Clutch overview 43
Mechanisms for safe driving 14 Structure and operation 44
Gear jump mechanism 14 Clutch operating mechanism 47
Reverse gear shift lever 1-way movement mechanism 15 Clutch master cylinder 48
Interlock mechanism 17 Checks and maintenance 50
Inadvertent reverse operation prevention mechanism 18 Failure diagnosis 53
Input shaft brake system (IBS) 20
IBS operation 21
Suzuki manual transmission & transaxle 24
Suzuki Alto (AMF310) transaxle overview 25
Gear shift mechanism 26
5th & Reverse Gear Shift Cam 26
Suzuki Swift (AZH) transaxle overview 28
Gear shift mechanism 29
Reverse Shift Prevention Mechanism
Construction 30
Suzuki Grand Vitara (JB424) manual transmission 32

TR01 Manual transmission & transaxle 3

 Lesson 1: Objectives

At the end of this lesson, you will be able to:

• Describe gear operating principles
• Explain the functions of the transmission.
• Describe the operating principles of the transmission.
Manual transmission • Describe the different types of gear shift mechanisms.
• Explain the function of synchromesh mechanism.
fundamentals • Describe the operating principles of the different
mechanisms for safe driving.
• Explain the operating principle of the IBS.

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 1.1 Overview Figure 1
[1] Input shaft
[2] Counter shaft
When a vehicle starts off, a large driving force is required even [3] Output shaft
through the engine rotation speed is low. When a vehicle is
driven at high speed, a high engine rotation speed is required (ii) Increasing torque and increasing engine rotation speed
even though the driving force is low. The transmission enables
the vehicle to meet these different requirements.

• Speed reduction (a small

A vehicle must also operate smoothly across many driving
gear rotates a larger gear)
conditions. For example, driving at high speed or slow speed, • Increasing the force
climbing up or going down hills, repeatedly stopping and (engine rotation speed
starting off and reversing. The transmission coverts engine drops)
rotation speed and engine torque in accordance with these
driving conditions and transmits them to the drive wheels.

1.2 Transmission functions

(i) The transmission transmits force by meshing gears • Changing gears
together.

• Speed increase (a larger

gear rotates a smaller
3 gear)
1 • Increasing the engine
rotation speed (force
2 drops)

Figure 1: Power transmission Figure 2: Increasing torque and increasing engine rotation speed

TR01 Manual transmission & transaxle 5

 (iii) A gear is added to change the rotation direction. 1.3 Structure and operation

1.3.1 Power transmission

A vehicle requires a large driving force when starting off, and

a high engine rotation speed when driving at high speed.
To achieve this, the transmission varies the engine rotation
speed and torque by changing the gear combinations (gear
ratio).
The engine power is transmitted to the transmission input
shaft via the clutch. The rotation of the input shaft is
transmitted to the output shaft gear via the countershaft
Figure 3: Reverse rotation gears. An output gear meshes to the output shaft through
synchro-mechanisms.
The rotation from the countershaft is transmitted to the
(iv) The transmission cuts off the power transmission by output shaft. In other words, the gear ratio is changed when
disconnecting the gear meshing. the sleeve moves in accordance with the shift lever position
and changes the gears on the output shaft.

1.3.2 Neutral position

When none of the gears on the output shaft mesh with the
gears on the counter shaft, the transmission is in the neutral
condition. This means that when the vehicle is stopped and
the engine is idling, the engine power rotates the input shaft,
countershaft and the gears on the output shaft, but the output
shaft does not rotate.

Figure 4: Power disconnection

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 Figure 5: Power transmission

1.3.3 Gear change

• 1st , 2nd and 3rd gear - Speed reduction (small gear rotates
a large gear)
• 4th gear - Direct connection (rotation is transmitted
unchanged)
• 5th gear - Speed increase (large gear rotates a small gear)
• Reverse gear - Reverse rotation (gear is added)

Figure 6: Gear change

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 1.3.4 Gear ratio

The gear ratio is the ratio between the input gear and output
gear rotation speeds. The gear ratio changes as the
transmission reduces or increases the engine rotation speed
with different gear combinations.

No. of output gears Input gear RPM

Gear ratio = No. of input gears = Output gear RPM

Output shaft torque

=
Input shaft torque
Figure 7: Gear ratios

For example, when the engine operates at a constant torque

and a constant speed, if the gear ratio is high (a small gear
rotates a large gear), then a high torque but a low engine
rotation speed are transmitted to the tires. If the gear ratio is
low, a low torque and a high engine rotation speed are In the time that a large gear with 20 teeth
transmitted to the tires. rotates once, a small gear with 10 teeth rotates
twice. In other words, the small gear rotates at
In this way, the relationship between the transmitted torque twice the speed of the large gear, but transmits
and engine rotation speed is determined by the ratio of only half the force.
meshed gear teeth. This means that the torque and the engine
rotation speed can be expressed as follows.

Engine torque X gear ratio = output shaft torque

Engine rotation speed
Gear ratio = Output shaft rotation speed

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 A gear is added to reverse the direction of rotation. Examples of gear ratios

Suzuki Kizashi A6B424 6MT

V1000 (km/h)
Number of teeth Gear ratio
215/60R16 215/55R17 235/45R18
1st 47/13 3.615 8.08 8.09 8.23
2nd 43/21 2.047 14.27 14.29 14.54
3rd 40/29 1.379 21.18 21.22 21.58
4th 35/34 1.029 28.39 28.43 28.92
5th 31/37 0.837 34.90 34.95 35.56
6th 29/41 0.707 41.32 41.38 42.09
Rev (44/13) x (36/35) 3.481 8.40 8.41 8.55

Suzuki SX4 RW420 J20B 6MT

Figure 8: Reverse gear V1000 (km/h)

Number of teeth Gear ratio
205/60R16 195/65R15 205/50R17
1st 47/13 3.615 8.00 7.80 7.88
2nd 43/21 2.047 14.14 13.78 13.91
3rd 40/29 1.379 20.98 20.45 20.65
4th 35/34 1.029 28.12 27.41 27.68
5th 31/37 0.837 34.57 33.70 34.02
6th 29/41 0.707 40.93 39.89 40.28
Rev (44/13) x (36/35) 3.481 8.32 8.11 8.19

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 1.3.5 Shift lever

The shift lever can be moved horizontally to select the gear row
(select movement), forward and back to move the gears (shift
movement).
These movements move the internal parts of the transmission
to change gear.

1.3.5.1 Remote control type

In remote control type, a rod or cable connects the shift lever

to the transmission. This type minimizes vibration and noise
because its use of anti-vibration rubber makes it difficult for
engine vibration to be transmitted.
Figure 10: Cable type shift mechanism.

1.3.5.2 Direct shift type

In direct shift type, the shift lever is directly connected to the

transmission. Most rear wheel drive vehicles use this system
because it delivers fast shift operations and feels good to
operate.

Figure 9: Rod type shift mechanism

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 1.4 Transmission operation

1.4.1 Gear change

The movement of the shift lever is transmitted unchanged to

the gear shift selector lever inside the transmission. When
the gear shift selector lever moves in the vertical direction
shown in the figure to select and rotate a gear, it moves the
synchronizer hub and meshes the gear with the main shaft.

1.4.2 What is the synchromesh mechanism?

The synchromesh mechanism selects the gear to mesh with

the main shaft by moving the synchronizer sleeve. When in
Figure 10: Direct shift mechanism. neutral, the gears on the main shaft rotate at a speed that is a
multiple of the teeth ratio (reduction ratio) of the gears that
oppose the rotation speed of the countershaft.

This means that the output shaft rotation speed and the
rotation speeds of the gears on the output shaft are different.
When the gears are changed, the synchromesh mechanism
absorbs this rotation difference to ensure a smooth change.

TR01 Manual transmission & transaxle 11

 1.4.3 Synchromesh mechanism operation

1st stage synchronization action

1. When the shift fork moves the synchronizer sleeve
(referred to as “sleeve” from now on), the sleeve and the
meshed key move together to the right.
2. The end of the key pushes the ring against the cone. This
frictional force transmits the rotation force of the sleeve
to the gear.
3. At this time, the difference between the rotation speeds of
the ring and gear and the friction with the cone shifts the
rotation direction of the gear just by the difference
between the key groove width and the key width. As such,
when seen from above, the splines on the inside of the
sleeve and the ends of the ring splines face each other in
different positions as shown in Figure 12.

Figure 11: Synchronizer mechanism

Figure 12: Synchronizer mechanism operation

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 2nd stage synchronization action 3rd stage synchronization meshing
1. As the shift lever is moved, the force acting on the sleeve 1. The sleeve and gear rotation speeds are equalized, and the
overcomes the spring. The sleeve goes over the key ring is freed in the rotation direction.
protrusion and moves forward (moves to the right in the 2. As shown in the figure below, the splines on the inside of
figure). the sleeve push away the ring splines and move smoothly
2. The splines on the inside of the sleeve and the ring splines to mesh with the gear splines.
hit against each other. 3. If there is a rotation difference between the ring or gear
3. The force applied to the sleeve is transmitted via the and the sleeve, the frictional force of the ring and the gear
splines that continue to hit and contact each other, and cone stops the forward movement of the sleeve. It only
strongly pushes the ring into the gear cone. This frictional allows forward movement after synchronization is
force performs a strong synchronization action. completed. However, when the synchronization action
(frictional force) is weak, there is a gear noise when
meshing with the gear and gear shifting is difficult.

Figure 13: Synchronizer mechanism operation

Figure 14: Synchronizer mechanism operation

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 1.4.4 Mechanisms for safe driving (i) Chamfer
The sleeve and gear spline fittings have tapered teeth
surfaces. During rotation, the gear spline is driven by the
A manual transmission has various mechanisms for safe
tapered surface, which makes it difficult for the gear to jump
driving. These include a mechanism for preventing a meshed
out.
gear from jumping out while driving, a mechanism for
preventing more than one gear from meshing to the main shaft
at the same time, and a mechanism for preventing the vehicle
from being mistakenly put into reverse while driving.

1.4.4.1 Gear jump mechanism

“Gear jump out” is when a gear jumps out without a shift

operation. It often occurs because of changes in vibration or
load while driving, such as during sudden acceleration or
deceleration. If the gear jumps out, the transmission goes into
neutral.
Gear jump out is often caused by gears meshing in a defective
way at the moment of shifting or by a shift in the positional Figure 15: Chamfer method to prevent gear jump
relationship between the sleeve and gear while driving due to
wear on the splines between the synchronizer sleeve and the
gear resulting in an excessive thrust clearance.

TR01 Manual transmission & transaxle 14

 (ii) Detent ball 1.4.4.2 Reverse gear shift lever 1-way movement
mechanism
The detent ball is pushed into the ball groove on the shift fork
shaft by the spring. This prevents gear jump out and gives a In a manual transmission, the shift lever is operated to move
good operating feel when shifting. the various shift fork shafts. The gear shift forks that are
integrated with the shift fork shafts move to change the
gears.
In recent Suzuki vehicles, changing to reverse has been
performed not by the sleeve movement, but by the movement
of the reverse idler gear.
Longitudinal manual transmissions use a reverse gear shift
lever 1-way movement mechanism. When a shift operation is
made that involves a movement in the direction of the 5th
gear side and the reverse side of the 5th-reverse shift fork,
the reverse gear shift lever 1-way movement mechanism is
activated only when the reverse gear shift lever is operated to
one side (reverse side). This mechanism moves the reverse
idler gear.

Figure 16: Detent ball method to prevent gear jump

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 (i) When in neutral (ii) Reversing
When in neutral, because the pin of the 5th-reverse gear shift When shifting from neutral to reverse, the pin of the 5th-
fork restricts the rotation of the reverse gear shift lever, the reverse shift fork moves along the groove of the reverse gear
reverse idler gear does not move. shift lever, applying force to the reverse gear shift lever in the
clockwise direction.
The clockwise rotation of the reverse gear shift lever moves
the reverse idler gear and fits it into the input shaft.

Figure 17: Neutral position

Figure 18: Neutral position

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 (iii) When in the 5th speed 1.4.4.3 Double meshing prevention mechanism
(interlock mechanism)
When shifting from neutral to the 5th gear, the pin of the 5th-
reverse gear shift fork moves inside the groove of the reverse If 2 adjacent shift forks move at the same time, there is a risk
gear shift lever, but because rotation force is not applied to the of 2 gears meshing. To prevent this, a double meshing
reverse gear shift lever, the reverse idler gear does not move. prevention mechanism (interlock mechanism) is used.

(i) Transverse manual transmission

When shifting to 1st or 2nd gear, locking ball A that is pushed
out by the low speed shift shaft moves the pin and locking
ball B. The balls enter the grooves of the high speed shift
shaft and the 5th shift shaft to regulate the movement of
these shift shafts.

Figure 18: Neutral position

Figure 19: Double meshing prevention

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 When shifting to 3rd or 4th gear, the high speed shift shaft 1.4.4.4 Inadvertent reverse operation prevention
moves locking balls A and B, which enter the grooves of the mechanism
low speed shift shaft and the 5th shift shaft to regulate the
An inadvertent reverse gear operation is when the gear jumps
movement in the shift direction.
out from 5th gear, and through its own momentum, enters the
reverse gear. To prevent this, the mechanism is designed so
that a shift to reverse gear cannot be made without first
returning the shift lever to neutral.

Transverse manual transmission

1. When the shift lever is moved to the 5th gear, the gear
shift selector shaft is pushed in the gear shift guide case
direction. At this time, the movement of the 5th-reverse
interlock plate is regulated by the guide bolt, and the low
select spring and the cam guide return spring are
compressed.

Figure 19: Double meshing prevention

When shifting to 5th or reverse gear, locking ball B that is

pushed out by the 5th shift shaft moves the pin and locking
ball A. The balls enter the grooves of the low speed shift shaft
and the high speed shift shaft to regulate the movement in the
shift direction.

Figure 20: Inadvertent reverse operation prevention mechanism

TR01 Manual transmission & transaxle 18

 2. The 5th-reverse gear shift cam that shifts to 5th gear 3. If shifting to reverse is performed in this condition, the
rotates, and the reaction force of the cam guide return gear shift selector shaft rotates, and the 5th-reverse gear shift
spring moves the 5th-reverse interlock plate one step to cam continues to be pushed by the 5th-reverse interlock
the rear. plate. This means that the shifting cannot be performed.

Figure 21: Inadvertent reverse operation prevention mechanism

Figure 22: Inadvertent reverse operation prevention mechanism

TR01 Manual transmission & transaxle 19

 4. When the shift lever is returned to the neutral position, the 1.4.4.5 Input shaft brake system (IBS)
reaction force of the low select spring returns the 5th-
reverse interlock plate to its normal position, which allows
shifting to reverse. When shifting into reverse, even if you step on the clutch to
cut off the power from the engine, inertial force continues to
rotate the input shaft. This means that when shifting into
reverse, the reverse gear of the input shaft that continues to
rotate and the reverse idler gear that is stationary are not
synchronized. This results in poor shifting into reverse gear
and a gear noise. To minimize this effect, the IBS applies a
brake to the input shaft with the 5th speed synchronizer ring
to reduce the rotation speed and ensure a smooth shift into
reverse.

Figure 23: Inadvertent reverse operation prevention mechanism

Figure 24: Without IBS (poor shifting and gear noise)

TR01 Manual transmission & transaxle 20

 (II) IBS operation

• When in neutral
When the input shaft is rotating due to inertial force, the 5th
speed synchronizer sleeve and 5th speed synchronizer lever
also rotate. As such, the 5th speed synchronizer lever pushes
out toward the circumference due to centrifugal force. This
meshes the flange of the 5th speed synchronizer lever with
the groove of the 5th speed synchronizer sleeve.

Figure 25: With IBS (improved shifting , reduced

gear noise)

(i) IBS structure

The IBS is made up of a 5th speed synchronizer sleeve, 5th
speed synchronizer hub, 5th speed synchronizer
lever, 5th speed synchronizer ring and input shaft 5th gear.

Figure 26: IBS operation: neutral position

Figure 26: IBS structure

TR01 Manual transmission & transaxle 21

 synchronizer ring and the cone surface of the input shaft 5th
gear make contact. This applies a brake to the input shaft,
reducing its speed. As such, it is easier for the reverse idler
gear and the input shaft reverse gear to mesh, enabling a
smooth shift into reverse.

Figure 27: IBS operation: neutral position: rotating components

• Start of synchronization
Figure 28: IBS operation: start of synchronization

When shifting into reverse, the 5th gear shift fork moves the
5th speed synchronizer sleeve in the direction, of arrow A. At
this time, the 5th speed synchronizer lever moves the flange of
the 5th speed synchronizer lever in the direction of arrow B
(figure 28), with the 5th speed synchronizer hub as the fulcrum
because the 5th speed synchronizer hub is fixed to the input
shaft. This means that the 5th speed synchronizer lever
pushes the 5th speed synchronizer ring, so that the 5th speed

TR01 Manual transmission & transaxle 22

 • Gear change completion

When the 5th speed synchronizer sleeve moves further in the

direction of arrow A, the 5th speed synchronizer lever is
pushed in the direction of arrow C. This eliminates the force of
the 5th speed synchronizer lever pushing against the 5th speed
synchronizer ring. At this time, the 5th speed synchronizer ring
and the cone surface of the input shaft 5th gear separate,
which releases the brake that was applied to the input shaft.
This means that after the gear change is completed, the input
shaft can rotate again.

Figure 30: Power transmission route

Figure 29: Gear change completion

TR01 Manual transmission & transaxle 23

 Lesson 2:
Objectives

At the end of this lesson, you will be able to:

• Explain the construction of the transmissions or transaxles
used in Suzuki vehicles.
• Identify the different components of the transmissions or

Suzuki manual transaxles.

• Explain the operation of the gear change mechanisms used

transmissions &
in the different models.

transaxle

TR01 Manual transmission & transaxle 24

 2.1 Suzuki Alto AMF310 transaxle overview

2.1.1 Construction
The transaxle provides five forward speeds and one reverse
speed by means of three synchromesh devices and three
shafts-input shaft, countershaft and reverse gear shaft. All
forward gears are in constant mesh and reverse uses a sliding
idler gear arrangement.
The low speed synchronizer sleeve & hub is mounted on
countershaft and engaged with countershaft 1st gear or 2nd
gear, while the high speed synchronizer sleeve & hub is done
on input shaft and engaged with input shaft 3rd gear or 4th
gear. The 5th speed synchronizer sleeve & hub on input shaft
is engaged with input shaft fifth gear mounted on the input
shaft. A double cone synchronizing mechanism is provided to
2nd gear synchromesh device for high performance of shifting
to 2nd gear. The countershaft turns the final gear and
differential assembly, thereby turning the front drive shafts
which are attached to the front wheels.

Figure 1

[1] 5th speed synchronizer sleeve & hub [2] Input shaft 5th gear
[3] Input shaft 4th gear [4] High speed synchronizer
sleeve and hub
[5] Input shaft 3rd gear [6] Left case
[7] Reverse gear shaft [8] Reverse idler gear
[9] Input shaft [10] Right case
[11] Side cover [12] Countershaft 5th gear
[13] Countershaft 4th gear [14] Countershaft Figure 1: Manual transaxle (Alto AMF310)
[15] Countershaft 3rd gear [16] Countershaft 2nd gear
[17] Low speed synchronizer speed & hub [18] Countershaft 1st gear
[19] Final gear [20] Differential case

TR01 Manual transmission & transaxle 25

 2.1.2 Gear Shift Mechanism [12] Gear shift interlock bolt [13] Gear shift & select lever
[14] Low speed gear shift shaft [15] High speed gear shift shaft
The gear shifting control system consists of the following main
[16] Gear shift control lever assembly
parts. Movement of gear shift control lever assembly (16) is
transmitted to gear shift & select shaft assembly (10) through
gear shift control cable (1) and gear select control cable (2). 2.1.3 5th & Reverse Gear Shift Cam
5th & reverse gear shift cam, cam guide return spring and 5th
to reverse interlock guide bolt are provided to prevent the
gear from being directly shifted from 5th to reverse.

Figure 2: Gear shift mechanism (Alto AMF310)

Figure 3: Gear shift cam

[1] Gear shift control cable [2] Gear select control cable
[3] Select cable lever [4] Shift cable lever
[5] 5th & reverse gear shift cam [6] 5th gear shift fork
[7] Reverse gear shift lever
[8] 5th & reverse gear shift guide shaft
[9] 5th & reverse gear shift shaft
[10] Gear shift & select shift assembly
[11] 5th to reverse interlock guide bolt

TR01 Manual transmission & transaxle 26

 A B C D
Figure 4: 5th and reverse gear shift cam

1. Figure 4 (A) 2. Figure 4(B)

When shift lever is at neutral position between 3rd and 4th When shift lever is shifted toward right from neutral position,
gear, 5th & reverse gear shift cam (2) is under 5th to reverse gear shift & select shaft (1) moves up but 5th & reverse gear
interlock guide bolt (5) and can turn freely clockwise (to 3rd shift cam (2) is restricted by 5th to reverse interlock guide
gear) and counterclockwise (to 4th gear). bolt (5) and cam guide return spring (3) is contracted.

[1] Gear shift & select shaft

[3] Cam guide return spring (expanded)
[4] 1st & 2nd select spring (expanded)

TR01 Manual transmission & transaxle 27

 3. Figure 4 (C) 2.2 Suzuki Swift (AZH model) transaxle
When shift lever is shifted to 5th gear, gear shift & select shaft overview
(1) turns clockwise letting 5th & reverse gear shift cam (2) off
from 5th to reverse interlock guide bolt and pushed up by cam
gear return spring (3). In this state, movement of shift cam is 2.2.1 Description
restricted by 5th to reverse interlock guide bolt (5) and The transaxle provides five forward speeds and one reverse
therefore, gearshift to reverse is not attainable. speed by means of three synchromesh devices and three
shafts,
• Input shaft,
3. Figure 4 (D)
• Countershaft and
When shift lever is shifted from neutral position between 3rd- • Reverse gear shaft.
4th gear to 5th & reverse gear position, gear shift & select
All forward gears are in constant mesh, and reverse uses
shaft (1) moves up but 5th & reverse gear shift cam (2) is
a sliding idler gear arrangement.
restricted to move up by 5th to reverse interlock guide bolt (5).
The low speed sleeve & hub is mounted on countershaft and
In this position, shift & select shaft can turn both clockwise (to engaged with countershaft 1st gear or 2nd gear, while the
5th gear) and counterclockwise (to reverse gear). high speed sleeve & hub is mounted on input shaft and
engaged with input shaft 3rd gear or 4th gear. The 5th speed
[3] Cam guide return spring (contracted) sleeve & hub on input shaft is engaged with input shaft 5th
gear mounted on the input shaft.
[4] 1st and 2nd select spring (contracted)
To prevent the cracking noise from the reverse gear when
shifting transaxle gear into the reverse gear, the reverse shift
braking device is used. This device utilizes the 5th
synchromesh, which is the lever synchro type, to apply the
brake on the input shaft rotation.

The double cone synchronizing mechanism is provided to 2nd

gear synchromesh device for high performance of shifting to
2nd gear.
For servicing, it is necessary to use genuine sealant or its
equivalent on mating surfaces of transaxle case which is
made of aluminum. The case fastening bolts must be
tightened to specified torque by means of torque wrench. It is
also important that all parts are thoroughly cleaned with
cleaning fluid and air dried before reassembling.

TR01 Manual transmission & transaxle 28

 Further, care must be taken to adjust preload of countershaft
taper roller bearings. New synchronizer rings are prohibited
from being lapped with respective gear cones by using lapping
compound before they are
assembled

2.2.1 Gear shift mechanism

The gear shifting control system

consists of the main parts shown in
figure 5. Movement of gear shift
control lever is transmitted to gear
shift & select shaft through gear
shift and gear select cables.

Figure 5
[1] Gear shift control cable
[2] Gear selector control cable
[3] Select cable lever
[4] Shift cable lever
[5] 5th gear shift fork
[6] Reverse gear shift lever
[7] 5th & reverse gear shift guide shaft
[8] 5th & reverse gear shift shaft
[9] Gear shift & select shaft assembly
[10] Gear shift interlock bolt
[11] Gear shift and select lever
[12] Low speed gear shift shaft
[13] High speed gear shift shaft
[14] Gear shift control lever assembly Figure 5: Gear shift mechanism – Suzuki Swift AZH414

TR01 Manual transmission & transaxle 29

 2.2.2 Reverse Shift Prevention Mechanism Operation
Construction 1. If shifting directly from 5th [a] to reverse [b] is attempted,
In the gear shift lever case, the reverse shift limit yoke (2) the cubic part of the gear shift & select lever (1) is
which turns around reverse shift limit yoke (2) retainer is blocked by the projection of the reverse shift limit yoke
provided. (2).
This reverse shift limit yoke (2) restricts the movement of gear
shift & select lever (1) to prevent erroneous reverse shifting.

Figure 7: Reverse shift prevention mechanism operation

[c] 4th

Figure 6: Gear shift & select shaft assembly

TR01 Manual transmission & transaxle 30

 2. Then the cubic part of the gear shift & select lever (1) 3. If the reverse shifting force is still applied to the shift lever,
pushes the projection of the reverse shift limit yoke (2). The the cubic part of the gear shift & select lever (1) rides over
reverse shift limit yoke (2) rotates and pushes the gear shift the projection of the reverse shift limit yoke (2), and the
& select lever (1) toward the neutral position. gear is shifted into the 4th. The reverse shift limit yoke (2)
returns to its original position.

Figure 9: Reverse shift prevention mechanism operation

Figure 8: Reverse shift prevention mechanism operation

[a] 5th
[a] 5th
[b] Reverse
[b] Reverse
[c] 4th
[c] 4th

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 2.3 Suzuki Grand Vitara (JB424) manual
transmission

Figure 10: Manual transmission – JB424

TR01 Manual transmission & transaxle 32

 Figure 10 Overview
[1] Input shaft
[2] Transmission front case The manual transmission consists of the input shaft, output
[3] Reverse idler gear shaft, countershaft and reverse shaft which are installed in
[4] Reverse idler shaft the die-cast aluminum alloy case. This transmission provides
[5] 4th gear five forward speeds and one reverse speed.
[6] High speed synchronizer hub
[7] 3rd gear
[8] Gear shift shaft The 1st, 2nd, 3rd and 4th speeds are for speed reduction
[9] Output shaft gear drive, 5th speed is for direct drive. The low speed (1st and
[10] Adapter case
[11] Output shaft 2nd) synchronizer is mounted on the countershaft and
[12] 5th speed synchronizer hub engaged with the countershaft 1st or 2nd gear. The high
[13] Countershaft speed (3rd and 4th) synchronizer is mounted on the input
[14] 2nd gear shaft and engaged with the input shaft 3rd and 4th gear.
[15] Transmission rear case
[16] Low speed synchronizer hub The 5th speed synchronizer is mounted on the input shaft and
[17] 1st gear engaged with the output shaft. The gear shift lever case is
[18] Reverse gear located at the upper behind the transmission case and has a
cam which prevents direct gear shifting from the 5th speed
gear into the reverse gear.
As the die-cast aluminum alloy case are sealed with liquid
type gasket, it is necessary to use genuine sealant or its
equivalent on its mating surface when reassembling them.
Also, the case fastening bolts must be tightened to specified
torque by means of the torque wrench and tightening over or
below the specified torque should be avoided.

TR01 Manual transmission & transaxle 33

 2.4 Suzuki SX4 (RW420) & Kizashi A6B424 6 2.4.1 Gear Shift Mechanism
speed manual transaxle overview The gear shifting control system consists of the following
main parts (shown in figure 11). Movement of gear shift
The transaxle provides six forward speeds and one reverse control lever is transmitted to gear shift & select shaft
speed by means of four synchromesh device (seven through gear shift and gear select cables
synchromesh devices in the A6B424) and three shafts
• input shaft,
• counter shaft and
• reverse gear shaft.
The low speed sleeve & hub is mounted on counter shaft and
engaged with counter shaft 1st gear or 2nd gear, while the high
speed sleeve & hub is done on input shaft and engaged with
input shaft 3rd gear or 4th gear. The 5th & 6th speed sleeve &
hub is mounted on input shaft and engaged with input shaft
5th gear or 6th gear. The reverse gear sleeve & hub mounted
on reverse gear shaft and engaged with reverse idler left gear
or reverse idler right gear.
The triple cone synchronizing mechanism is provided to 1st
and 2nd gear synchromesh devices for high performance of
shifting to 2nd gear.
The double cone synchronizing mechanism is provided to 3rd
gear synchromesh device for high performance of shifting.
For servicing, it is necessary to use genuine sealant or its
equivalent on mating surfaces of transaxle case. It is also
important that all parts are thoroughly cleaned with cleaning
fluid and air dried before reassembling.
Further, care must be taken to adjust between case and shaft Figure 11: Gear shift mechanism – A6B424
to thrust clearance of input shaft and counter shaft.
Synchronizer rings are prohibited from being lapped with [a] Vehicle forward [b] Direction of gear shift
[c] Direction of gear select [1] Gear shift control lever knob
respective gear cones using lapping compound before they are
[2] Gear shift control lever boot [3] Gear shift control cable
assembled [4] Gear select control lever [5] Gear shift control lever assembly
[6] Gear shift & select shaft assembly
[7] Reverse gear shift lever
[8] Gear shift interlock bolt

TR01 Manual transmission & transaxle 34

 2.4.2 Transaxle components 1. Input shaft
2. Input shaft 6th gear
3. 5th & 6th gear sleeve & hub
4. Input shaft 5th gear
5. Input shaft 4th gear
6. High speed sleeve & hub
7. Input shaft 3rd gear
8. Left reverse idler gear
9. Reverse gear sleeve
10. Right reverse idler gear
11. Reverse gear shaft
12. Left case
13. Right case
14. Countershaft 6th gear
15. Countershaft 5th gear
16. Countershaft 4th gear
17. Countershaft 3rd gear
18. Countershaft 2nd gear
19. Low speed sleeve & hub
20. Countershaft 1st gear
21. Countershaft
22. Final gear
23. Differential case

TR01 Manual transmission & transaxle 35

 Lesson 3:
Objectives

At the end of this lesson, you will be able to:

• Explain the important points that must be considered
during disassembly.
• Describe the different checks for internal transmission

Overhaul parts.
• Explain the important points that must be considered
during transmission assembly.
• Explain the different types of possible causes for different
transmission malfunctions.

TR01 Manual transmission & transaxle 36

 3.1 Important points for disassembly 3.2 Checks of internal transmission parts

There may be various reasons for disassembling the 3.2.1 Transmission case check
transmission, such as abnormal noise or stiff shifting. But Check mainly for cracks and that the breather plug functions
before performing the disassembly, you must first check for properly. If the plug is clogged, clean it.
possible causes in locations other than the transmission unit.

For example, if the shift operation is stiff, if you disconnect the 3.2.2 Gear teeth surface check
gear shift control cable on the transmission side and check Check the gear teeth surfaces for excessive wear or damage.
the shift lever movement, you can judge whether or not the If a gear is worn or damaged, replace it because it may cause
cause is on the transmission side. With some transmission abnormal noise.
types, actual parts can be moved to identify the cause while
only one side of the case is disconnected (before 3.2.3 Bearing check
disassembling the transmission). These include the condition
of the gear backlash and gear meshing, the chattering of Clean the ball bearings and roller bearings and then rotate
them. Check that they operate smoothly and do not catch.
each shaft, and the smoothness of the rotation of each gear Also check the parts equivalent to the outer race and inner
and shaft. race in the taper roller bearing, and replace them as a set if
there are any problems.
During disassembly, arrange the disassembled parts so that Check the bushes for wear, streaks and cracks, and replace
you remember to which system they belong. Be especially them as a set if there are any problems.
careful of transmission internal parts, because many of these
parts have a specific assembly direction. Make sure that you
remember the correct assembly method by taking notes or
3.2.4 Synchromesh mechanism check
marking the parts.
i. If the clearance is equal to or below the specified value
when the synchronizer ring and its partner gear are
pushed together, replace the synchronizer ring. Also, if
there is major wear on the gear cone, replace as a set.

TR01 Manual transmission & transaxle 37

 3.2.6 Shift fork check
Measure the thickness of each shift fork claw and the width
of the synchronizer sleeve groove, and replace if their values
deviate from the standard.

Figure 1: Synchromesh mechanism check

ii. Replace if there is significant wear on the synchronizer key

protrusion. Check for wear on the synchronizer sleeve that
covers the protrusion
iii. Replace if there is any breaking or attenuation on the key
spring.
Figure 2: Shift fork check

3.2.5 Shift lever check

Check for wear on the ball on the end of the shift lever, and
replace if there are any problems.

TR01 Manual transmission & transaxle 38

 3.2.7 Check of parts in the interlock mechanism and 3.3 Important points for assembly
gear jump out prevention mechanism
The important points for assembly are to make sure that the
Check parts such as the interlock pin, spring and locking balls, correct parts are installed in the correct areas, in the correct
and replace if there are any problems such as damage, direction and in the correct position. Information such as the
attenuation or wear. allowance of each part before disassembly and the force
required for operations must be noted down in advance. By
performing this check in every stage, you can prevent
maintenance mistakes, such as discovering after reassembly
that the gears are too stiff to shift.

3.4 Failure diagnosis

The transmission is connected to the engine, and its rotation

speed changes in proportion to the vehicle speed and
together with the differential and tires. As such, if a problem
occurs, the cause is not necessarily in the transmission.
When performing failure diagnosis for the transmission, first
the conditions and phenomena under which the problems
occur must be checked and the structure understood. The
possible locations must then be narrowed down to find the
cause.

TR01 Manual transmission & transaxle 39

 3.4.1 Abnormal noise 3.4.2 Gear engagement and disengagement problems

Most of the parts inside the transmission are sliding parts, such Likely gear shift operation problems are (1) shift lever to gear
shift control cable, and (2) shift shaft to shift fork to synchro-
as gears, bearings and the synchro-mechanism. If all parts in
mechanism. When the transmission side of the gear shift
the transmission are covered by an oil film they will not wear. control cable is disconnected and the shift lever is operated,
But if wearing occurs, chattering will occur in the sliding parts, if the movement is stiff, the problem is likely to be in system
resulting in abnormal noise. (1) above. If the movement is light, the problem is likely to be
in system (2).
So in general, the conditions under which the abnormal noise
occurs must be identified, and the operating parts that are During normal shift operation, the driver steps on the clutch
related to these conditions must be checked. Sometimes and the engine power is not transmitted to the transmission.
abnormal noise occurs only when driving with certain gears or For this reason, the same problems occur if the clutch is not
only when shifting to certain gears above can be used to fully disengaged.
identify the problem. But if the problem occurs across all
driving ranges, the cause may be in many different locations, 3.4.3 Gear jump out
such as the differential, wheel hub, clutch, propeller shaft and
drive shaft. Gear jump out may occur more easily during a sudden forward
movement. Gear jump out may occur because of changes
in vibration or load after the gears meshed in a defective way
at the moment of shifting. Or it may occur because part
wearing caused a shift in the positional relationship between
the synchronizer sleeve and gear. To make a final
identification of the cause, the transmission must be
disassembled.

To check, shift to the gear that has the problem and make
sure it is properly meshed. Repeatedly perform sudden
acceleration and deceleration to generate sudden forward
movements, and check the gear jump out phenomenon. Also
carefully check the shift feeling (operation feel, weight) while
operating the shift.

TR01 Manual transmission & transaxle 40

 3.4.4 Oil leaks 3.4.5 Manual transaxle symptom diagnosis

Clean the location where you suspect there is an oil leak.

Perform a driving test and check the oil leak location. Be
aware that breather clogging and overfilling may cause oil
Condition Possible cause
Worn shift fork shaft
leaks.
Worn shift fork or synchronizer sleeve

Gears slipping out of mesh Wear or damaged locating springs

Worn bearings on input shaft or
countershaft
Worn chamfered tooth on sleeve and
gear
Inadequate lubricant
Improper clutch pedal free travel
Distorted or broken clutch disk
Damaged clutch pressure plate
Figure 3: Oil level [3] oil filler hole Worn synchronizer ring
Hard shifting Worn chamfered tooth on sleeve and
gear
Worn gear shift control shaft joint
bushing
Distorted shift shaft

Broken gear shift/select control cables

Inadequate or insufficient lubricant

Damaged or worn bearings
Noise
Damaged or worn gears

Damaged or worn synchronizer parts

TR01 Manual transmission & transaxle 41

 Lesson 4:
Objectives

At the end of this lesson, you will be able to:

• Explain the function of the clutch and its components.

Describe the basic construction of clutch components.
Clutch
•
• Explain the different types of clutch release mechanisms.
• Explain the function and operation of the clutch master
cylinder
• Describe how the clutch pedal height inspection is
performed.
• Describe how the clutch release margin can be checked.
• Describe how the cylinder push rod play can be checked.
• Describe how the vehicle and be inspected to determine if
any clutch malfunction exists.
• Using clutch wear pattern, identify the possible cause of
clutch failure.

TR01 Manual transmission & transaxle 42

 4.1 Overview

Location
The clutch is positioned between the engine and the
transmission.

Function
The clutch connects and disconnect the engine to the manual
transmission. When engaged, the clutch transmits the engine
power using the frictional force between the clutch disc and
plate, and the force that pushes down these parts.

The clutch is made up of an operation mechanism, which

transmits the operation force of the driver through a clutch
cable or hydraulic pressure, and a clutch unit that receives this
force and connects and disconnects the power transmission.

Figure 1: Clutch mechanism

TR01 Manual transmission & transaxle 43

 and splines.
4.2 Structure and operation
The clutch disc is press fitted between the flywheel and
4.2.1 Clutch unit pressure plate by the spring force of the diaphragm spring. In
4.2.1.1 Clutch unit structure other words, the engine power is transmitted to the
transmission input shaft via the frictional force between the
The clutch unit components include a clutch disc, clutch cover
clutch disc, flywheel and pressure plate.
and release bearing.

4.2.1.2 Clutch disc structure

• Clutch disc
Clutch facing, which is a frictional material, is riveted to both
sides of the clutch disc. There is a clutch hub in the center of
the clutch disc into which the transmission’s input shaft is
inserted. The clutch facing must have an appropriate friction
coefficient. Its friction coefficient must not change much
with temperature variations.

• Damper spring
The clutch hub is sandwiched between plates to its front and
rear, and is constructed so that the clutch can move in a
circle (rotation direction) via the damper spring. It absorbs
and dampens the rotation impact when the clutch is
connected.
Figure2: Clutch unit components

A diaphragm spring and a pressure plate are assembled to the

clutch cover. They are fixed to a flywheel with bolts. The
clutch disc is installed between the flywheel and clutch cover
(pressure plate), and is fitted into the transmission input shaft

TR01 Manual transmission & transaxle 44

 Figure 3: Clutch disc structure

TR01 Manual transmission & transaxle 45

 4.2.1.3 Diaphragm spring clutch operation

When the clutch is connected, the spring force of the

diaphragm spring pushes the clutch disc strongly against the
flywheel via the pressure plate. This means that the clutch
plate rotates together with the flywheel so that the power from
the engine is always transmitted to the transmission. When
the driver steps on the clutch pedal to cut off the power, the
release fork pushes the release bearing against the end of the
diaphragm spring.
At this time, the pivot ring (wire ring) becomes the fulcrum and
the diaphragm spring outer circumference bends back. The
retracting spring (retainer plate) moves the pressure plate to
the right. This creates a gap between the friction surfaces of
the clutch disc, the power from the engine is cut off. Figure 4: Clutch connection & disconnection

TR01 Manual transmission & transaxle 46

 4.3 Clutch operation mechanism 4.3.2 Hydraulic operation mechanism
The components of this system include a clutch pedal, master
cylinder, release cylinder, release fork and pipe. The pedal
4.3.1 Mechanical operation mechanism force (1) (2) is transmitted by hydraulic pressure (3) to the
In this system, the clutch pedal and release fork are connected release fork (4).
with a clutch cable. When the driver steps on the clutch pedal The hydraulic operation mechanism delivers reliable operation
(1), the clutch cable is pulled (2) (3), and the release fork that is light and smooth. However, it has a complex structure,
pushes the release bearing onto the diaphragm spring (4). and if air enters the clutch fluid, it results in improper
When the driver releases the clutch pedal, the spring force of operation in the same way as in the brake hydraulic system
the return spring and diaphragm spring returns the release fork (becomes difficult to disengage the clutch). Attention must
and clutch pedal to their home positions and power is also be paid to the clutch fluid level.
transmitted to the transmission.

Figure 6: Hydraulic clutch mechanism

Figure 5: Mechanical clutch mechanism

TR01 Manual transmission & transaxle 47

 4.4 Master cylinder At the same time, the fluid pressure inside the cylinder rises
rapidly. The clutch fluid is sent to the operating cylinder and
moves the release piston.
The master cylinder is made up of a cylinder section in which a
piston slides a long distance, and a reservoir tank that stores
the clutch fluid. The master cylinder generates the hydraulic When the driver releases the clutch pedal, the piston
pressure for operating the clutch. To generate the hydraulic is returned by the spring force of the return spring and
pressure, when the driver steps a little on the clutch pedal, the the hydraulic pressure drops. This makes the clutch
piston is pushed and the clutch fluid inside the cylinder is sent fluid return from the operating cylinder side. Also,
to the reservoir tank. When the driver steps more on the because the spring retainer pulls the connecting rod,
clutch pedal, the piston moves and releases the connecting
the inlet valve opens the inlet return common port. This
rod, which up to now had been pulled by the spring retainer.
The spring force of the small conical spring that is built in to connects the reservoir tank with the master cylinder,
the connecting rod moves the inlet valve to the left and cuts and the master cylinder is filled with clutch fluid.
off the inlet return common port.

Figure 8: Master cylinder-brake pedal depressed

Figure 7: Master cylinder-brake pedal depressed

TR01 Manual transmission & transaxle 48

 4.4.1 Operating cylinder
The hydraulic pressure generated by the clutch master cylinder
acts on the piston. It acts as a force that moves the piston.
Also, together with the tension from the piston spring, it Principle of leverage
operates the clutch via the push rod and the release fork. The
bore of the operating cylinder is larger than the bore of the The “principle of leverage” is the way that a small force
master cylinder, which reduces the pedal force required when changes to a large force depending on the distance ratio
operating the clutch. between the fulcrum, effort (point of force) and load (point
of operation). This “principle of leverage” applies to the
clutch pedal, release fork and diaphragm spring.

Figure 9: Clutch master cylinder

This means that the long but light movement of the clutch
pedal can be used to operate the short but heavy movement
of the pressure plate.

TR01 Manual transmission & transaxle 49

 4.5 Checks and maintenance
Pascal’s principle
When pressure of a certain force per unit area is applied to one 4.5.1 Clutch pedal inspection
area of a fluid in a sealed container, regardless of its shape, the
(NB: AZH models used for description)
pressure is transmitted undiminished to all areas of the fluid.
4.5.1.1 Clutch pedal height inspection
When pressure is applied to a sealed fluid, force of the same
Measure distance between free position (1) and fully
strength (force per unit area) is generated in all parts.
depressed position (2) on clutch pedal shown by “a” in figure.
Using this “Pascal’s principle”, the force is increased by making If clutch pedal height is out of specification, replace pedal arm
the area of the operating cylinder larger than the master and/or clutch master cylinder (3).
cylinder.

Figure 10: Clutch pedal height inspection

TR01 Manual transmission & transaxle 50

 4.5.1.2 Cylinder push rod play 4.5.1.4 Clutch Release Margin

Press clutch pedal (1) gradually with finger, stop when slight
increase of resistance is felt and measure how much pedal has
moved (shown by “a” in figure).
If “a” is not within specification, replace master cylinder (3) or
pedal arm (2).

Figure 12: Clutch release margin

1) Apply parking brake fully and block wheels.

2) Start engine and keep engine at idle in neutral position.
3) Without clutch pedal (1) depressed, slightly push the shift
Figure 11: Cylinder push rod play
lever to reverse position until transaxle emits gear contact
noise. Do not shift the lever to reverse position.
4.5.1.3 Clutch Pedal Free Travel
4) While listening to gear contact noise, slowly depress clutch
Depress clutch pedal (1), stop the moment clutch resistance is pedal (1) and stop it when gear contact noise died
felt, and measure how much pedal has moved (shown by “b” in
figure). If “b” is not within specification, check pedal arm (2) (release point).
and master cylinder (3) and replace defective part.

TR01 Manual transmission & transaxle 51

 5) Measure distance between release point (4) and full stroke
point (5) on clutch pedal (1) shown by “c” in the figure. Bleeder plug
If “c” is not within specification, air may be trapped in
clutch system. Bleed air from clutch system.
Upon completion of above inspection, start engine and
check clutch for proper operation.

4.5.2.5 Air bleeding of clutch system

CAUTION:
• Brake fluid (Clutch fluid) is extremely damaging to paint. If
fluid should accidentally touch painted surface, immediately
wipe fluid from paint and clean painted surface.

• When operating the clutch pedal for air bleeding, after

releasing the clutch pedal, be sure to wait 1 second or more
before depressing it again. Otherwise, the oil seal of
operating cylinder will be damaged, resulting in oil leakage.

Perform in the same way as air bleeding for the brake hydraulic
system, but also pay attention to the following.
• During the air bleeding operation, make sure that the fluid
level does not drop to half or less.
• After bleeding the air, tighten the bleeder plug to the
specified torque.

TR01 Manual transmission & transaxle 52

 4.6 Failure diagnosis 4.6.2 Slipping

4.6.1 Engagement defect If slipping occurs between the clutch disc and pressure plate,
it may impair the transmission of power from the engine to
the transmission and cause acceleration problems. For this
To check for engagement defect, first put the transmission reason, be careful during diagnosis because this problem is
into the 1st gear while stepping on the clutch pedal. Next, easy to mistake for an engine failure. Check carefully whether
put the transmission into the neutral position, step on the the origin of the problem is in the operation mechanism or
accelerator pedal to raise the engine rotation speed, and the clutch unit.
then return the transmission to the 1st gear. At this time,
continue stepping down on the clutch pedal. If an abnormal Before performing the check, pull up the parking brake, place
wheel blocks around the tires and fully stop the vehicle.
noise (gear noise) occurs during the above operations, you
Then, step on the clutch pedal, put the transmission into the
can diagnose the problem as engagement defect. In the
4th gear, and slowly connect the clutch while slowly raising
engagement defect check, you must determine whether
the engine rotation speed. If the engine stops at this time,
the engagement defect occurs because the movement the clutch is in a good condition. But if the engine does not
distance of the pressure plate is too short, or whether the stop and the vehicle does not move forward, you can
engagement defect is caused by a clutch unit problem where conclude that the clutch is slipping.
the clutch disc cannot separate from the flywheel and pressure
plate.

TR01 Manual transmission & transaxle 53

 4.6.3 Unsmooth engagement 4.6.5 Abnormal noise

Check carefully whether the cause is insufficient smoothness Continuous abnormal noise may be caused by defects in the
in the operation mechanism, or uneven transmission torque pilot bearing, release bearing or input bearing, or in bearings
caused by a defect in the clutch unit. Check carefully because inside the transmission.
this may also cause the engine output to drop or other
problems. While the vehicle is stopped and the engine is operating, if the
To perform the check, start the engine, step on the clutch abnormal noise stops when you step on the clutch pedal, the
pedal, put the transmission into the 1st gear and slowly defect is probably in a bearing inside the transmission. If the
connect the clutch. If there is no uncomfortable vibration at abnormal noise does not stop at this time, the defect is
this time, you can conclude that the clutch unit is in a good probably in the release bearing or the pilot bearing.
condition.
Sometimes, a temporary abnormal noise is made during
4.6.4 Sudden forward movement (jumping out) acceleration or deceleration while the clutch is engaged. In
such cases, depending on the noise type and the conditions
under which it occurs, you must check not only the clutch
Sudden forward movement is a symptom where the vehicle and transmission, but also parts such as the engine mount
does not start off smoothly. The vehicle may jump forward and drive belt.
automatically when the clutch pedal is operated, or the engine
may feel like it will stop.
Check carefully whether the cause of the sudden forward
movement is insufficient smoothness in the operation
mechanism, or uneven transmission torque caused by a defect
in the clutch unit.
To perform the check, start the engine, put the transmission
into the 1st gear or reverse and slowly connect the clutch. If
the vehicle does not start off suddenly, you can conclude that
the clutch unit is in a good condition.

TR01 Manual transmission & transaxle 54

 Summary

• The clutch is used to connect and disconnect the engine

from the manual transmission
• The clutch disc consists of a splined hub and a round metal
plate covered with friction material.
• The release bearing is usually a ball bearing and collar
assembly that reduces friction between the pressure plate
levers and the clutch fork.
• A clutch release mechanism allows the driver to disconnect
the clutch from the engine.
• The release mechanism can use either a cable or hydraulic
pressure.
• A worn clutch disc will cause clutch slippage and sometimes
damage the flywheel.
• A bad pressure plate can also cause clutch slippage and
clutch release problems.
• A worn pilot bearing will allow the transmission input shaft
and clutch disc to wobble up and down. This can cause
clutch vibration, abnormal noises and damage to the
transmission.
• Clutch slippage causes the engine to race (engine speed
increases quickly) without an increase in the vehicle’s road
speed.

TR01 Manual transmission & transaxle 55

 Reference
C
The following abbreviations can be used in this CAN Controller Area Network
training manual CKP Crankshaft Position
CMP Camshaft Position
A CO Carbon Monoxide
A/B Air Bag CO2 Carbon Dioxide
ABDC After Bottom Dead Center CPP Clutch Pedal Position
ABS Anti-lock Brake System CPU Central Processing Unit
AC Alternating Current CVT Continuously Variable Transmission,
A/C Air Conditioning Continuously Variable Transaxle
A-ELR Automatic-Emergency Locking Retractor
A/F Air Fuel Ratio
D
ALR Automatic Locking Retractor
DC Direct Current
API American Petroleum Institute
APP Accelerator Pedal Position D/C Driving Cycle
A/T Automatic Transmission, Automatic Transaxle DLC Data Link Connector
ATDC After Top Dead Center DOHC Double Over Head Camshaft
ATF Automatic Transmission Fluid, Automatic DOJ Double Offset Joint
Transaxle Fluid DOT Department of Transportation
AWD All Wheel Drive DPF® Diesel Particulate Filter
API American Petroleum Industry DRL Daytime Running Light
DTC Diagnostic Trouble Code (Diagnostic Code)
B
D/C Driving Cycle
BARO Barometric Pressure
BBDC Before Bottom Dead Center
BCM Body electrical Control Module
BTDC Before Top Dead Center
B+ Battery Positive Voltage
BB+ Battery Positive Voltage for Backup

TR01 Manual transmission & transaxle 56

 E I
EBD Electronic Brake Force Distribution IAC Idle Air Control
ECM Engine Control Module IAT Intake Air Temperature
ECT Engine Coolant Temperature IMT Intake Manifold Tuning
ISC Idle Speed Control
ECU Electronic Control Unit
ISO International Organization for Standardization
EEPROM Electrically Erasable Programmable Read Only
Memory
J
EFE Heater Early Fuel Evaporation Heater
JIS Japanese Industrial Standards
EGR Exhaust Gas Recirculation J/B Junction Block
EGT Exhaust Gas Temperature J/C Junction Connector
ELR Emergency Locking Retractor
ENG A-Stop Engine Auto Stop Start L
EPS Electronic Power Steering L Left
ESP® Electronic Stability Program LCD Liquid Crystal Display LED Light Emitting Diode
EVAP Evaporative Emission LHD Left Hand Drive vehicle
LIN Local Interconnect Network
G LO Low
LSPV Load Sensing Proportioning Valve
GND Ground
GPS Global Positioning System
M
GL Gear libricant MAF Mass Air Flow
MAP Manifold Absolute Pressure
H Max Maximum
HVAC Heating, Ventilating and Air Conditioning MFI Multiport Fuel Injection
HC Hydrocarbons Min Minimum
HFC Hydro Fluorocarbon MIL Malfunction Indicator Lamp (“CHECK ENGINE”
HI High Light or “SERVICE ENGINE SOON” Light)
M/T Manual Transmission, Manual Transaxle
HO2S Heated Oxygen Sensor

TR01 Manual transmission & transaxle 57

 N T
NOx Nitrogen Oxides TCC Torque Converter Clutch
TCM Transmission Control Module
O
OBD On-Board Diagnostic system TCSS Traction Control Support System
OCM Occupant Classification Module TDC Top Dead Center
OCV Oil Control Valve TP Throttle Position
O/D Overdrive TPMS Tire Pressure Monitoring System
OHC Over Head Camshaft
TWC Three-Way Catalytic converter
O2S Oxygen Sensor

P U
PCM Powertrain Control Module UART Universal Asynchronous Receiver / Transmitter
PCV Positive Crankcase Ventilation USB Universal Serial Bus
PM Particulate Mater
PNP Park / Neutral Position
P/S Power Steering V
PSP Power Steering Pressure VFD Vacuum Fluorescent Display
VIN Vehicle Identification Number
R VSS Vehicle Speed Sensor
R Right
VVT Variable Valve Timing
RAM Random Access Memory
RHD Right Hand Drive Vehicle
ROM Read Only Memory W
RPM Engine Speed WU-OC Warm Up Oxidation Catalytic converter
WU-TWC Warm Up Three-Way Catalytic converter
S
SAE Society of Automotive Engineers
SDM Sensing and Diagnostic Module (Air Bag Controller, Other
Air bag Control Module) 2WD 2-Wheel Drive
SDT Smart Diagnostic Tester 4WD 4-Wheel Drive
SFI Sequential Multiport Fuel Injection
SI System International
Note: ESP is a trademark of Daimler AG
SOHC Single Over Head Camshaft
DPF® is a trademark of HJS Fahrzeugtechnik GmbH & Co KG and Suzuki is
SRS Supplemental Restraint System the trade mark licensee.

TR01 Manual transmission & transaxle 58

 Well done, you have now completed
the “TR02 Manual transmission &
transaxle” online training course!

Please take the online exam

TR01 Manual transmission & transaxle 59