Transmission ISUZU TF SERIES 2004 Workshop Manual

7B1-48 MANUAL TRANSMISSION

12. Apply engine oil to the needle bearing (10) and the
3rd gear (9) thrust surfaces.
Install the needle bearing (10) and the 3rd gear (9)
to the mainshaft.
The 3rd gear dog teeth must be facing the
transmission front side.

226RS056
13. Install 3rd block ring (8).
14. Check and install 3rd-4th synchronizer assembly (7)
by the following steps:
1. Check that the inserts (3) fit snugly into the
clutch hub insert grooves.
2. Check that the insert springs (4) are fitted to the
inserts as shown in the illustration.
3. Check that the clutch hub (5) and the sleeve (6)
slide smoothly.
4. Install the synchronizer assembly to the
mainshaft.
The clutch hub face with the heavy boss must be
facing the 3rd gear side.

226RW221

226RS049
15. Select and install mainshaft snap ring(6) in the
following way:
Select the snap ring which will provide the minimum
clearance between the 3rd-4th clutch hub and the
snap ring.

226RS058
There are three snap ring sizes available.
The snap rings are color coded to indicate their
thickness as shown in the figure.

MANUAL TRANSMISSION 7B1-49


226RS021
Clutch Hub and Snap Ring Clearance
Standard: 0 - 0.1 mm (0 - 0.004 in)

Snap Ring Availability
Thickness Color Coding
1.80 mm (0.071 in) White
1.85 mm (0.073 in) Yellow
1.90 mm (0.075 in) Blue


Use a pair of snap ring pliers to install the snap
ring to the mainshaft.
The snap ring must be fully inserted into the
mainshaft snap ring groove.
16. Install top block ring (5).
Apply grease to the needle bearing (4) inner and
outer circumferences and install needle bearing (4)
in the top gear shaft (2).
17. Use a bench press to install the top gear shaft ball
bearing (3) to the top gear shaft (2).

226RS059
The snap ring groove of the ball bearing (3) must be
facing the transmission front side.
18. Use a pair of snap ring pliers to install the top gear
shaft snap ring (1) to the top gear shaft (2).

7B1-50 MANUAL TRANSMISSION

Main Data and Specifications
General Specifications
MUA 5G MUA 5S
Transmission type Fully synchronized forward and reverse gears
Control method Remote control with the gear shift lever on the floor.
Gear ratio: Transmission 1st 4.008 4.357
2nd 2.301 2.502
3rd 1.427 1.501
4th 1.000 1.000
5th 0.828 0.809
Rev. 3.651 3.970
Transmission oil capacity 2.95 lit. (3.12 US qt)
Type of lubricant Engine oil: Refer to the chart in "SECTION 0"

MANUAL TRANSMISSION 7B1-51

Torque Specifications

RTW47BLF001201
About arrow mark, refer to Transmission (MUA) Installation in this section.

7B1-52 MANUAL TRANSMISSION

Torque Specifications (Cont'd)

RTW47BLF000901

MANUAL TRANSMISSION 7B1-53

Torque Specifications (Cont'd)

RTW47BLF000601

7B1-54 MANUAL TRANSMISSION

TROUBLESHOOTING
1. ABNORMAL NOISE

1) NOISY IN NEUTRAL

Checkpoint Trouble Cause Countermeasure

Replenish or replace the gear
oilInsufficient or improper gear
oil NG
Mainshaft splines
Synchronizer clutch hub
splinesReplace the main shaft and
the synchronizer clutch hub
Replace the gear(s)
Replace the flywheel pilot
Worn splines
Worn or scuffed gear tooth
contact surfaces
Flywheel pilot bearingWorn flywheel pilot bearing
Bearings (Mainshaft,
countershaft, and transfer
shaft)
Gears (Mainshaft,
countershaft, reverse idler
gear and transfer gears)
Replace the bearing(s)Worn or broken bearing(s)
OK
NG NG NG NG OK
OK
OK
Gear oil
TransmissionRealign the transmissionTransmission misalignment OK
NG

MANUAL TRANSMISSION 7B1-55

2) NOISY OPERATION

Checkpoint Trouble Cause Countermeasure

Replenish or replace the gear
oilInsufficient or improper engine
oil NG
Replace the gear(s)
Replace the gear(s)
Replace the bearing(s)
Gears (Gear whining)Lack of backlash between
meshing gears
Free running gears seizing on
the thrust face or the inner
face
Bearings (Hissing, thumping
or bumping)Worn or broken bearing(s)
Gears (Squealing at high
speeds)
Replace the gear(s)Gears (Growling, humming, or
grinding)Worn, chipped, or cracked
gear(s)
NG NG NG NG OK
OK
OK OK
Gear oil (Metallic rattling)

7B1-56 MANUAL TRANSMISSION

2. HARD SHIFTING

Checkpoint Trouble Cause Countermeasure

Change lever play
Clutch pedal free play
Repair or replace the
applicable parts and regrease
Readjust the clutch pedal free
play
Worn change lever sliding
portions
Improper clutch pedal free
play
Change lever operationRepair or regrease the change
lever assembly
Replenish or replace the
engine oil
Hard operating change lever
caused insufficient grease
Insufficient or improper gear
oil
OK
OKNG NG NG NG
OK OKGear oil
Continued on the next page
Shift rod and quadrant box
sliding faces, and other partsReplace the shidt rod and/or
the quadrant boxWorn shift rod and/or sliding
faces
Repair or replace the sleeveSleeve movement failure
NG NG
OKShift block sleeve movement

MANUAL TRANSMISSION 7B1-57

Checkpoint Trouble Cause Countermeasure

Synchronizer assembly
Shift arm and synchronizer
sleeve
Replace the worn parts
Replace the worn parts
Worn synchronizer parts
Worn shift arm and/or
synchronizer sleeve groove
Mainshaft and countershaft
thrust playReplace the worn partsWorn thrust washer, collar,
and/or gear thrust faces
OK
NG NG NG
OK OK
Continued from the previous