differential ISUZU TF SERIES 2004 Repair Manual

MANUAL TRANSMISSION 7B1-5

Rear Oil Seal (4





2)
Disassembled View
220R300030
Legend

(1) Rear Propeller Shaft (2) Rear Oil Seal

Removal
1. Raise and support vehicle with suitable jack stands.
2. Remove propeller shaft flange yoke bolts and nuts
at the differential side.
3. Remove center bearing from crossmenber.
4. Remove prepeller shaft from the transmission main
shaft spline.
Refre to the section “Rear Propeller Shaft”.
5. Use a screwdriver to pry the rear oil seal from the
rear cover.

Installation
1. Install a new oil seal (2) using the installer 5-8522-
0050-0.



220RS044
2. Insert the splined yoke into the transimission
mainshaft spline.
3. Install the propeller shaft flange yoke to the drive
pinion flange.

MANUAL TRANSMISSION 7B1-9

6. Remove gear control lever (5).
7. Raise and support vehicle with suitable stands.
8. Remove rear propeller shaft (6).
NOTE: Apply alignment marks on the flange at the
differential side.

401RS023
9. Loosen the front exhaust pipe fixing nuts (7) at the
engine side but not remove them. (Diesel engine
only)
150R300003

10. Remove the exhaust pipe (8). (6VE1 only)
RTW37ASH0001
11. Disconnect harness connectors and clips on the
transmission.

Neutral Switch


Back up Switch

Car Speed Sensor
12. Remove the fuel pipe bracket (9) with pipes from the
transmission (17).
Diesel engine
220R300012

Legend
(1) Bolt
(2) Nut
(3) Fuel Pipe Assembly

7B1-66 MANUAL TRANSMISSION

6. Remove gear control lever (5).
7. Raise and support vehicle with suitable stands.
8. Remove rear propeller shaft (6).
NOTE: Apply alignment marks on the flange at the
differential side.
9. Remove front propeller shaft (7).
NOTE: Apply alignment marks on the flange at both
front and rear sides.
401RS023
10. Loosen the front exhaust pipe fixing nuts (8) at the
engine side but not remove them. (Diesel engine
only)
150R300004
11. Remove the exhaust pipe (9). (6VE1 only)
RTW37ASH000101
12. Disconnect harness connectors and clips on the
transfer.


Actuator connector


Car Speed Sensor

810R300069

Legend
(1) Neutral Switch Connector: Transmission
(2) Back up Switch Connector
(3) Speed Sensor Connector
(4) Actuator Connector
(5) 2W - 4W Switch Connector
(6) Neutral Switch Connector: Transfer

7D1-34 TRANSFER CONTROL SYSTEM

Diagnosis
Before determining a trouble (Non-trouble mode)
1. When shifting from 2H to 4H:
1-1-1 When the flashing frequency of the 4WD indicator is changed from 2Hz to 4Hz (Shft on the fly)
If the load is too large to shift the gears synchronously, the operation is repeated up to 3 times. If the shifting
is not effected after being repeated 3 times, the indicator frequency is changed from 2Hz to 4Hz and, at the
same time, the actuator condition is changed to 2H, indicator flashes at 4Hz for 10 seconds, and then goes
out.
Cause of excessive synchronous shifting load

Extremely low temperature (the oil viscosity of the front differential increases requiring a large load for
synchronization)
 High speed (since the difference of relative revolutions of gears to be shifted synchronously is too large,
required work load per unit time becomes larger).
Step 1-1-1:
Stop the vehicle or decrease the speed and operate as required again.

1-1-2 When the flashing frequency of the 4WD indicator is changed from 2Hz to 4Hz (Rigid and free wheel
Hub) / Block out of meshing spline.
Step 1-1-2:
Run the vehicle forward and backward several meters and operate as required again.

1-2 When the flashing of 4WD indicator at 2Hz continues more than 11.5 seconds (repetition of 3 times of
above No.1 is counted) (Shift on the fly)
If there is difference of revolutions and phases between the front wheel and axle, connecting the front wheel
and axle is difficult.
Until shifting in the transfer and connection of the front wheel and axle are completed

, the indicator flashes
at a frequency of 2Hz. In the above case, the indicator continues flashing at a frequency of 2Hz until the
connection of the front axle is completed. (If the shifting in the transfer is not completed, the flashing
frequency is changed to 4Hz (above No.1).)
By correcting the difference of relative revolutions and deviation of phases, the shifting can be completed.
Step 1-2:
While the vehicle is running, make sure of safety around the vehicle and accelerate or decelerate the
vehicle while going straight.
When the vehicle is at a stop, run the vehicle forward and backward several meters.

2.
When shifting from 4H to 2H
2-1 When 4WD indicator continues flashing at 2Hz
When shifting from 4H to 2H, the 4WD indicator continues flashing at 2Hz until separation in the transfer and
the separation of the front wheel axle are completed
. When torsional torque is accumulated in the drive
system, separation in the transfer and separation of the front axle
is difficult. In such a case, they can be
separated by removing the torsional torque of the drive system.
Step 2-1:
While the vehicle is running, make sure of safety around the vehicle and accelerate or decelerate the
vehicle while going straight.
When the vehicle is in stop, run the vehicle several meters forward and backward.


: Shift on the fly only.

7A3-16 ON-VEHICLE SERVICE (AW30 –40LE)

Evaluation
i. If there is no 1 
2 upshift:

Solenoid S2 is stuck
 1 –2 shift valve is stuck
ii. If there is no 2 
3 upshift:

Solenoid S1 is stuck
 2 –3 shift valve is stuck
iii. If there is no 3 
OD upshift (throttle valve opening
1/2):

Solenoid S2 is stuck
 3 –OD shift valve is stuck
iv. If the shift point is defective: Refer to TROUBLESHOOTING CHART in this
section.
v. If the lock-up is defective: Refer to TROUBLESHOOTING CHART in this
section.
2. In the same manner, check the shock and slip at the 1 
2, 2 
3 and 3 
OD upshifts.
NOTE: Drive the vehicle on level ground.
Evaluation
If the shock is excessive:
Refer to TROUBLESHOOTING CHART in this section.
3. Run at “D" range lock-up or OD gear and check fo
r
abnormal noise and vibration.
NOTE: The check for the cause of abnormal noise and
vibration must be made with extreme care as it could
also be due to loss of balance in the propeller shaft,
differential, the torque converter, etc. or insufficient
bending, rigidity, etc. in the power train.



RUW37ASH000201

4. While running in “D" range, 2nd, 3rd gears and OD,
check to see that the possible kick-down vehicle
speed limits for 2 1, 3 1, 3 2, OD 3 and
OD 
2 kick-downs conform to those indicated on
the automatic shift diagram.



RUW37AMH000101
5. Check for abnormal shock and slip at kick-down.
6. While running in “D" range, OD gear or “lock-up",
shift to “2" and “L" ranges and check the engine
braking effect at each of these ranges.
7. Also check to see that downshift is made from 3 
2
or from OD to 3 and then to 2 immediately and that
2 
1 downshift point is within the limits shown in the
diagram when tested by releasing the accelerato
r
pedal and shifting into position of “L" while driving in
the third gear or in overdrive.

ON-VEHICLE SERVICE (AW30 –40LE) 7A3-43

Removal
NOTE: Before removing transmission and transfer
assembly from vehicle, change the transfer mode to
2WD using the 4WD push button switch on dash panel.
1. Disconnect battery ground cable.
2. Raise and support vehicle with suitable stands.
3. Remove front propeller shaft.(4WD only)
NOTE: Apply alignment marks on the flange at both
front and rear sides.
4. Remove rear propeller shaft.
NOTE: Apply alignment marks on the flange at the
differential side.


401RS023
5. Remove the middle exhaust pipe.



RTW37ASH0001

6. Disconnect the transfer harness connectors and the
clips.(4WD only)

Speed sensor
 2W-4W shift actuator
NOTE: Avoid turning the vehicle ignition switch to the
ON position when the 2WD-4WD connector is removed
(battery connected).
If the ignition switch must be turned to the ON position,
the controller must first be removed (memory must be
cleared because the CHECK 4WD INDICATOR will
light).
7. Support transfer case with a transmission jack.(4WD only)
8. Remove the transfer case assembly from the
transmission.(4WD only)
9. Disconnect the shift cable.
10. Remove the fuel pipe clips with the fuel pipes from the brackets and put aside it. Remove the fuel pipe
brakets from the transmission.






P1010010
11. Discinnect the transmission harness connectors
and clips.
12. Remove the oil level gauge and the guide tube.
13. Remove the suspension crossmember.

DIAGNOSIS (JR405E) 7A2-107
No. B10: Brake is Applied in R Range

Description:

Brake is applied suddenly in R range.

Diagnosis Hints:

Basically a trouble in the AT main unit. However, some trouble in the sensor system or output system may have
some influence on the trouble in the main unit and therefore these systems should be also checked to prevent
reproduce of the trouble.

Possible Cause:

Seized clutch (low clutch, high clutch, 2-4 brake).

Shortage or faulty quality of ATF.

Trouble in control valve body (faulty operation, sticking, clogged oil passage).

Disordered select cable (select indicator light indicates R but the hydraulic system is not in the R range).

Malfunction of parking mechanism.


No. B11: Insufficient Starting or Shaking in D Range

Description:

Insufficient starting or shaking in D range.

Possible Cause:

Slip of clutch (low clutch, low one-way clutch, reverse clutch, low & reverse brake).
If slip of clutch is caused, a DTC (gear ratio error) is stored.

Shortage or faulty quality of ATF.

Dropped line pressure.

Trouble in control valve body (faulty operation, sticking, clogged oil passage).


No. B12: Noise or Vibration is Generated at Starting

Description:

Noise or vibration is generated in the vicinity of AT at starting.

Diagnosis Hints:

Cause other than AT can be also considered. It is effective means to reproduce a running condition using a lift
up, chassis dynamo, etc. to investigate the origin (generating condition) of noise and vibration.
Caution:
Lifting up some unit to test it accompanies danger. Provide safety measures as far as possible and
carry out the test with sufficient care.

Possible Cause:
Following sources of noise or vibration other than the AT can be considered.

Noise from differential gears.

Noise from propeller shaft.

The bearing support in the middle of the propeller shaft has fatigued, and the bend angle of the propeller shaft
has changed, causing vibration at the time of start.

Unbalanced and poor uniformity of tires cause vibration.

7A2-130 DIAGNOSIS (JR405E)
No. F2: Engine Races Up During Acceleration (Slip)

Description:

The engine speed up when the accelerator pedal is stepped on for acceleration and the gear is shifted up or
down.

Only the engine speeds up but vehicle speed does not increase when the accelerator pedal is stepped on for
acceleration during the running.

Diagnosis Hints:

Basically same causes as "No. C1 - C8: Engine races up (slip) by shift up or shift down" are considered.
When the condition of No. C1-C8 grows worse, symptom of No. F2 results.




No. F3: Noise or Vibration During the Running in R, D, 3, 2 or L Range

Description:

Noise or vibration is generated in the vicinity of AT during the running.

Diagnosis Hints:

Cause other than AT can be also considered. It is effective means to reproduce a running condition using a lift
up, chassis dynamo, etc. to investigate the origin (generating condition) of noise and vibration.
Caution:
Lifting up some unit to test it accompanies danger. Provide safety measures as far as possible and
carry out the test with sufficient care.

Possible Cause:
Following sources of noise or vibration other than the AT can be considered.

Noise from differential gears.

Noise from propeller shaft.

The bearing support in the middle of the propeller shaft has fatigued, and the bend angle of the propeller shaft
has changed, causing vibration at the time of start.

Unbalanced and poor uniformity of tires cause vibration.




No. F4: Engine Brake Does Not Apply in L Range

Description:

The engine brake does not apply, allowing the vehicle to run freely when the accelerator pedal is released at low
speed in L range.

Possible Cause:

Slip of clutch (low & reverse brake)
If slip of clutch is caused, a DTC (gear ratio error) is stored.

Faulty input/output signal system.
Low & reverse brake duty solenoid

Faulty control valve (faulty operation, sticking).

7A2-146 DIAGNOSIS (JR405E)

5. If there is no reverse.

Reverse clutch malfunction.

Reverse clutch hydraulic circuit failed.

Low & reverse brake hydraulic circuit failed.

Low & reverse brake duty solenoid stick.
Refer to symptom diagnosis "No. A2: Vehicle Dose Not
Run in R Range" or DTC section "Low & Reverse
Brake Duty Solenoid Failure".
6. If there is no parking.

Parking pawl malfunction.
Refer to symptom diagnosis "No. G1: Vehicle Moves in
P Range or Parking Gear in Not Disengaged othe
r
than P Range".

NOTE:
The check for the cause of abnormal noise and vibration
must be made with extreme care as it could also be due to
loss of balance in propeller shaft, differential, the torque
converter, etc. Or insufficient bending, rigidity, etc. in the
powertran.