ISUZU TF SERIES 2004 Workshop Manual
Page 3141 of 4264
MSG MODEL 7B-23
TOP GEAR SHAFT, MAINSHAFT GEAR AND COUNTER GEAR
Disassembly Steps
1. Top shaft snap ring
2. Top gear shaft
3. Ball bearing
4. Needle bearing
5. 4th block ring
6. Mainshaft snap ring
7. 3rd - 4th synchronizer assembly
8. 3rd block ring
9. 3rd gear
10. Needle bearing
11. Mainshaft ball bearing
12. 1st gear thrust washer
13. 1st gear
14. Needle bearing collar
15. Needle bearing
16. 1st block ring
17. 1st - 2nd synchronizer assembly
18. 2nd block ring
19. 2nd gear
20. Needle bearing
21. Mainshaft
22. Rear ball bearing
23. Bearing snap ring
24. Front ball bearing
25. Counter gear
Page 3142 of 4264
7B-24 MSG MODEL
Important Operations
1. Top Gear Shaft Snap Ring
2. Top Gear Shaft
3. Ball Bearing
1) Use a pair of snap ring pliers to remove the snap ring.
2) Use a bench press and the bearing remover to remove the
ball bearing.
Bearing Remover : 5-8840-0015-0 (J-22912-01)
7. 3rd - 4th Synchronizer Assembly
1) Remove the synchronizer assembly as a set.
2) Disassembly the synchronizer assembly.
1 Springs
2 Sleeve
3 Clutch Hub
4 Inserts
11. Mainshaft Ball Bearing
Use a bench press and the bearing remover to remove the ball
bearing.
Bearing Remover : 5-8840-0015-0 (J-22912-01)
17. 1st - 2nd Synchronizer Assembly
1) Remove the synchronizer assembly as a set.
2) Disassembly the synchronizer assembly.
1 Springs
2 Sleeve
3 Clutch Hub
4 Inserts
22. Rear Ball Bearing
24. Front Ball Bearing
Use a bench press and the bearing remover to remove the ball
bearing.
Bearing Removar : 5-8840-0015-0 (J-22912-01)
Page 3143 of 4264
MSG MODEL 7B-25
INSPECTION AND REPAIR
Make the necessary adjustments, repairs, and part replacements if excessive wear or damage is discovered during
inspection.
SHIFT ARM THICKNESS
Use a micrometer to measure the shift arm thickness.
If the measured value is less than the specified limit, the shift
arm must be replaced.
Shift Arm Thickness mm(in)
Standard Limit
1st-2nd 9.6-9.8 (0.378-0.386) 9.0 (0.354)
3rd-4th 6.95-7.2 (0.273-0.283) 6.5 (0.256)
Rev.-5th 6.8-6.9 (0.268-0.272) 6.3 (0.248)
DETENT SPRING FREE LENGTH
Use a venier caliper to measure the detent spring free length.
If the measured value is less than the specified limit, the
detent spring must be replaced.
Detent Spring Free Length mm(in)
Standard Limit
25.6 (1.01) 23.6 (0.93)
DETENT SPRING TENSION
Use a spring tester to measure the valve spring tension.
If the measured value is less than the specified limit, the valve
spring must be replaced.
Valve Spring Tension N(kg/lb)
Compressed
Height mm(in)Standard Limit
22.1 (0.870)61.8-65.7
(6.3-6.7/13.9-14.8)55.9
(5.7/12.6)
BLOCK RING AND DOG TEETH
CLEARANCE
Use a thickness gauge to measure the clearance between the
block ring and the dog teeth.
If the measured value exceeds the specified limit, the block
ring must be replaced.
Block Ring and Dog Teeth Clearance mm(in)
Standard Limit
1st,2nd 2.0 (0.078) 1.3 (0.051)
3rd, 4th, 5th 1.5 (0.059) 0.8 (0.032)
Page 3144 of 4264
7B-26 MSG MODEL
BLOCK RING AND INSERT CLEARANCE
Use a thickness gauge to measure the clearance between the
block ring and the insert.
If the measured value exceeds the specified limit, the block
ring and the insert must be replaced.
Block Ring and Insert Clearance mm(in)
Standard Limit
1st,2nd 3.46-3.74 (0.136-0.147)
3rd, 4th, 5th 3.51-3.79 (0.138-0.149)4.0 (0.157)
CLUTCH HUB AND INSERT CLEARANCE
Use a thickness gauge to measure the clearance between the
clutch hub and the insert.
If the measured value exceeds the specified limit, the clutch
hub and the insert must be replaced.
Clutch Hub and Insert Clearance mm(in)
Standard Limit
0.01 - 0.19 (0.0004 - 0.0075) 0.3 (0.012)
MAINSHAFT RUN - OUT
1. Install the mainshaft to a grinding machine.
2. Use a dial indicator to measure the mainshaft central
portion run-out.
If the measured mainshaft run-out exceeds the specified
limit, the mainshaft must be replaced.
Mainshaft Run - Out mm(in)
Limit
Less than 0.03 (0.0012)
GEAR INSIDE DIAMETER
Use an inside dial indicator to measure the gear inside
diameter.
If the measured value is less than the specified limit, the gear
must be replaced.
Gear Inside Diameter mm(in)
Standard Limit
1st
Rev.45.00-45.01
(1.7717-1.7720)45.10 (1.7756)
2nd
3rd41.00-41.01
(1.6142-1.6146)41.10 (1.6181)
5th34.03-34.04
(1.3398-1.3402)34.10 (1.3425)
Page 3145 of 4264
MSG MODEL 7B-27
REVERSE IDLER GEAR AND IDLER
GEAR SHAFT CLEARANCE
1. Use a micrometer to measure the idler gear shaft diameter.
2. Use an inside dial indicator to measure the idler gear inside
diameter.
3. Calculate the idler gear and idler gear shaft clearance.
Idler gear inside diameter - idler gear shaft diameter = idle
r
gear and idler gear shaft clearance.
If the measured value exceeds the specified limit, the idle
r
gear and/or the idler gear shaft must be replaced.
Idler Gear and Idler Gear Shaft Clearance mm(in)
Standard Limit
0.041 - 0.074 (0.0016 - 0.0029) 0.150 (0.0059)
CLUTCH HUB SPLINE PLAY
1. Set a dial indicator to the clutch hub to be measured.
2. Move the clutch hub as far as possible to both the right and
the left.
Note the dial indicator reading.
It the measured value exceeds the specified limit, the
clutch hub must be replaced.
Clutch Hub Spline Play mm(in
)
Standard Limit
0.019 (0 - 0.075) 0.20 (0.0079)
Page 3146 of 4264
7B-28 MSG MODEL
BALL BEARING PLAY
Use a dial indicator to measure the ball bearing play.
Ball Bearing Play mm(in)
Limit
0.2 (0.0079)
FRONT COVER OIL SEAL
Oil Seal Replacement
Oil Seal Removal
Use a screwdriver to pry the oil seal from the front cover.
Oil Seal Installation
1. Use the oil seal installer to install the oil seal to the front
cover.
Oil Seal Installer : 5-8840-0026-0 (J-26540)
2. Apply engine oil to the oil seal lip.
REAR COVER OIL SEAL
Oil Seal Replacement
Oil Seal Removal
Use a screwdriver to pry the oil seal from the rear cover.
Oil Seal Installation
1. Use the oil seal installer to install the oil seal to the rear
cover.
Oil Seal Installer : 5-8522-0050-0 (J-29769)
2. Apply engine oil to the oil seal lip.
Page 3147 of 4264
MSG MODEL 7B-29
REASSEMBLY
MAJOR COMPONENT
INTERNAL PARTS
Reassembly steps
1. Top & main gear shaft assembly
2. Counter gear shaft assembly
3. Rev. and 5th gear assembly
4. Shift fork assembly & interlock pin
5. Detent assembly
Page 3148 of 4264
7B-30 MSG MODEL
MINOR COMPONENTS
TOP GEAR SHAFT, MAINSHAFT GEAR AND COUNTER GEAR
Reassembly Steps
1. Mainshaft
2. Needle bearing
3. 2nd gear
4. 2nd block ring
5. 1st-2nd synchronizer assembly
6. 1st block ring
7. Needle bearing collar
8. Needle bearing
9. 1st gear
10. 1st gear thrust washer
11. Mainshaft ball bearing
12. Needle bearing
13. 3rd gear
14. 3rd block ring
15. 3rd-4th synchronizer assembly
16. Mainshaft snap ring
17. Needle bearing
18. 4th block ring
19. Top gear shaft
20. Ball bearing
21. Top gear shaft snap ring
22. Counter gear
23. Front ball bearing
24. Bearing snap ring
25. Rear ball bearing
Page 3149 of 4264
MSG MODEL 7B-31
Important Operations
2. Needle Bearing
3. 2nd Gear
1) Apply the engine oil to the 2nd needle bearing and the 2nd
gear.
2) Install the needle bearing and the 2nd gear to the
mainshaft.
The dog teeth of the 2nd gear must be facing the rear side
of the transmission.
5. 1st-2nd Synchronizer Assembly
1) Apply the engine oil to the clutch hub spline.
2) Install the synchronizer assembly to the mainshaft.
The outside sleeve heavy chamfering must be facing the
rear of the transmission.
1 Chamfer Angle = 30
2 Chamfer Angle = 45
7. Needle Bearing Collar
Use a bench press and the collar installer to install the needle
bearing collar.
Collar Installer : 5-8840-0178-0 (J-33851)
8. Needle Bearing
9. 1st Gear
1) Apply the engine oil to the 1st needle bearing and the 1st
gear.
2) Install the needle bearing and the gear to the mainshaft.
The dog teeth of the 1st gear must be facing the front side
of the transmission.
10. 1st Gear Thrust Washer
Install the thrust washer to the mainshaft.
The thrust washer oil groove must be facing the 1st gear side.
Page 3150 of 4264
7B-32 MSG MODEL
11. Mainshaft Ball Bearing
1) Apply the engine oil to the ball bearing inside
circumference.
2) Use a bench press and the bearing installer to install the
bearing.
The bearing snap ring groove must be facing the front o
f
the transmission.
Bearing Installer : 5-8840-0015-0 (J-22912-01)
12. Needle Bearing
13. 3rd Gear
1) Apply the engine oil to the 3rd needle bearing and the 3rd
gear.
2) Install the needle bearing and the gear to the mainshaft.
The dog teeth of the 3rd gear must, be facing the front side
of the transmission.
15. 3rd-4th Synchronizer Assembly
1)
Apply the recommended lubricating oil to the clutch hub
spline.
2) Install the synchronizer assembly to the mainshaft.
The sleeve light chamfering
1 and the clutch hub heavy
boss
2 must be facing the rear of the transmission.
16. Mainshaft Snap Ring
1) Select the snap ring which will provide the minimum
clearance between the mainshaft and the snap ring.
There are four snap ring sizes available.
The snap rings are numbered to indicate their thickness.
Mainshaft and Snap Ring Clearance mm(in)
Standard
0 - 0.05 (0.002)
Snap Ring Availability mm(in)Thickness Identification Number
1.50 (0.059) 1
1.55 (0.061) 2
1.60 (0.063) 3
1.65 (0.065) 4
2) Use a pair of snap ring pliers to install the snap ring to the
mainshaft.