Page 953 of 1449
REAR AXLE -Special Tools27B-7
Tool UseName Number
MB990850End yoke holderDRemoval of the self-locking nut
DAdjustment of the drive pinion turning
torque
MB990339Bearing pullerDrive pinion rear bearing inner race removal
MB990648Bearing remover
B A
MB990835
A: MB990836
B: MB990392Drive pinion setting
gauge set
A: Drive pinion
gauge assem-
bly
B: Cylinder
gaugeAdjustment of drive pinion height
MB990988Side gear holding
tool setMeasurement of clutch plate preload (vehicles
with mechanical LSD)
MB990728Side & rear bearing
inner race installerPress-fitting of drive pinion rear bearing inner
race
MB990727Oil seal installerPress-fitting of drive pinion oil seal
MB990813Ta pRemoval of adhesive
Page 955 of 1449

REAR AXLE -Troubleshooting 27B-9
ERASING THE DIAGNOSIS CODES
Connect the MUT-IIto the 16-pin diagnosis connector and
erase the diagnosis code. (Refer to GROUP 00 – How to
Use Troubleshooting/Inspection Service Points.)
Caution
Turn the ignition switch to the LOCK (OFF) position before
connecting or disconnecting the MUT-II.
INSPECTION CHART FOR DIAGNOSIS CODE
Diagnosis
code No.Diagnosis itemsReference page
12Power supply voltage (valve power supply) systemopen- or short-circuitRefer to
GROUP22
13Failsafe relay system open- or short-circuit
GROUP22.
21FR wheel speed sensor systemopen- or short-circuit
22FL wheel speed sensor systemopen- or short-circuit
23RR wheel speed sensor systemopen- or short-circuit
24RL wheel speed sensor systemopen- or short-circuit
25Wrong-diameter tire
26Wheel speed sensor (faulty output signal)
31Steer sensor (ST-1, ST-2, ST-N) systemopen- or short-circuit
32Steer sensor (ST-N) systemshort-circuit
33fixed
34Steer sensor (ST-1, ST-2) systemshort-circuit or output
fixed
41TPS systemopen-circuit or ground
42short-circuit
45Pressure sensor systemopen-circuit or ground
46open earth
47abnormal power supply
51G sensor (longitudinal) systemopen- or short-circuit
52defective sensor
56G sensor (lateral) systemopen- or short-circuit
57defective sensor
Page 962 of 1449

REAR AXLE -On-vehicle Service27B-16
DATA LIST REFERENCE TABLE
For check, refer to GROUP 22.
ACTUATOR TEST REFERENCE TABLE
For check, refer to GROUP 22.
CHECK AT 4WD-ECU TERMINALS
For check, refer to GROUP 22.
ON-VEHICLE SERVICE
REAR AXLE TOTAL BACKLASH CHECK
1. Park the vehicle on a flat, level surface.
2. Move the transmission control lever to the neutral position.
Apply the parking brake. Raise the vehicle on a jack.
3. Turn the companion flange clockwise as far as it will go.
Make the mating mark on the dust cover of the companion
flange and on the differential carrier.
4. Turn the companion flange anti-clockwise as far as it
will go, and measure the amount of distance the mating
marks moved.
Limit: 6 mm
5. If the backlash exceeds the limit value, replace the
differential carrier assembly.
GEAR OIL LEVEL CHECK
1. Remove the filler plug.
2. Check that the gear oil level is within the specified range
from the bottom end of the filler plug hole.
3. If the gear oil level exceeds the standard value, add the
specified gear oil up to the bottom end of the filler plug
hole.
Specified gear oil:
Hypoid gear oil
MITSUBISHI Genuine Gear Oil Part No. 8149630
EX, CASTROL HYPOY LS (GL-5, SAE 90),
SHELL-LSD (GL-5, SAE 80W - 90) or equivalent
4. Fit the filler plug and tighten it to the specified torque.
Tightening torque: 49±9 N·m
Mating marks
Upper
limit
Lower
limit
Gear oil
8mm
Page 965 of 1449

REAR AXLE -On-vehicle Service27B-19
FLUID LEVEL CHECK
1. Remove the maintenance lid located in the luggage
compartment.
2.
If the vehicle has been run, leave it for 90 min. or more
in an ordinary temperature (10_C–30_C) to allow the
accumulator internal pressure to drop.
NOTE
If the ambient temperature is 10_C or less, allow more
time to leave the vehicle to stand idle.
Set MUT-IIto 16 pin diagnostic connector. Turn the ignition
switch to the ON position, operate MUT-II, drive the
hydraulic unit (item No.03) forcibly, release the pressure in
the accumulator.
Caution
Turn the ignition switch to the LOCK (OFF) position
before connecting or disconnecting the MUT-II.
NOTE
(1) To drive (oil level check mode) forcibly, turn the
directional valve of the hydraulic unit 20 turns from
side to side, release the differential automatically.
Drive can also be cleared forcibly using the Clear
key of MUT-II.
(2) If the function has been stopped by fail safe, the
hydraulic unit can not be cleared forcibly.
3. Check that the fluid level in the oil reservoir is in the
range between MAX and MIN.
4. If the fluid level is lower than MIN, add the specified
fluid.
Specified fluid: ATF-SP III
5. Reinstall the maintenance lid.
BLEEDING
1. Lift up the vehicle.
2. Set the MUT-IIto the 16-pin diagnosis connector.
Caution
Turn the ignition switch to the LOCK (OFF) position
before connecting or disconnecting the MUT-II.
3. Turn the ignition switch to the ON position.
4. Set the steering wheel in the straight-ahead position.
5. Operating the MUT-II, drive the hydraulic unit (item No.02)
forcibly.
NOTE
(1) Drive the bleeding mode forcibly for 5 minutes, release
the operation automatically. Drive can also be cleared
forcibly using the Clear key of MUT-II.
(2) If the function has been stopped by fail safe, the
hydraulic unit cannot be cleared forcibly.
Page 966 of 1449

REAR AXLE -On-vehicle Service27B-20
6. Remove the cap of the left bleeder screw on the torque
transfer differential and connect a vinyl hose.
7. Gradually turn the steering wheel clockwise from the
straight-ahead position. At this time, loosen the left bleeder
screw and check that fluid is discharged with air.
8. After air has been completely discharged, tighten bleeder
screw and turn the steering wheel in the straight-ahead
position.
Caution
While the system is being bled of air, add fluid as
necessary to ensure that it is left in the oil reservoir
during the entire procedure.
9. Repeat steps 6 and 7 two to three times until no air
bubbles are recognized in the fluid that comes out. Then,
tighten the bleeder screw to the specified torque.
Tightening torque: 9±1 N·m
10. Perform steps 5 through 8 for the right bleeder screw.
Note, however, that the steering wheel should be turned
conterclockwise.
11. When removing the hydraulic unit, bleed the fluid line
in ACD side. (Refer to GROUP 22 – On-vehicle Service.)
12. After the system has been completely bled of air, check
for the fluid level. (Refer to P. 27B-19.)
Caution
If the system is not completely bled of air, the hydraulic
unit could generate noise, degrading pump durability.
AYC OPERATION CHECK
1. Lift up the vehicles.
2. Set the MUT-IIto the 16-pin diagnosis connector.
Caution
Turn the ignition switch to the LOCK (OFF) position
before connecting or disconnecting the MUT-II.
3. Start the engine.
4. Set the gear to the 2nd gear or above, operate MUT-II,
and check from the service data (Item No.09) that the
wheel speed is within 10 km/h to 20 km/h.
NOTE
(1) Set the steering wheel to the neutral position.
(2) When turning the steering wheel, AYC operates
continually (operation sound from the torque transfer
differential), but it is not system fault. In this case,
set the steering wheel to the neutral position, and
perform the following operations in order to stop the
ACD.
DRelease the clutch.
DSet the gear to ”Neutral”.
DStop the engine.
Bleeder
screw
Vinyl hose
Page 967 of 1449

REAR AXLE -On-vehicle Service27B-21
5. Operate the MUT-II, drive the torque transfer differential
(item No.06 and 07) forcibly.
NOTE
(1) Drive the clutch operating mode forcibly for 1 minutes,
release the operation automatically. Drive can also
be cleared forcibly using the Clear key of MUT-II.
(2) If the hydraulic unit function has been stopped by
fail-safe, the torque transfer differential cannot be
forcibly driven.
6. Operating the MUT-II, by service data (item no.07 and 08),
check the condition of the wheel speed below.
The left rear wheel is faster 2km/h than right rear wheel.
The right rear wheel is faster 2km/h than left rear wheel.
NOTE
If the above are not satisfied, check the oil pressure as
the system may be faulty.
OIL PRESSURE CHECK
1. Lift up the vehicle.
2. Set the MUT-IIto the 16-pin diagnosis connector.
Caution
Turn the ignition switch to the LOCK (OFF) position
before connecting or disconnecting the MUT-II.
3. Turn the ignition switch to ON.
4. Disconnect the hydraulic unit and the hydraulic unit hose
assembly, connect the special tool to L port, put the lid
to R port or connect the hydraulic unit hose assembly
disconnected from L port to R port.
5. Operating the MUT-II, drive the hydraulic unit forcibly
(item No.02).
NOTE
(1) Drive the operation check mode of the clutch left
side for 1 minutes, release the operation automatically.
Drive can also be cleared forcibly using the Clear
key of MUT-II.
(2) If the function has been stopped by fail safe, the
hydraulic unit cannot be cleared forcibly.
6. Check that the generated oil pressure of the hydraulic
unit satisfies the standard value.
Standard value: 0.9 – 1.1 MPa
Caution
While the oil pressure is checked, add fluid as
necessary to ensure that it is left in the oil reservoir
during the entire procedure.
7. Check the oil pressure of the clutch right side following step
4 through 6. Connect the special tool to R port, put the lid
to L port or hydraulic unit hose assembly disconnected
from R port to L port, use the MUT-IIdrive item No.07
(operation check mode of clutch right side) forcibly.
MD998330
MB991705
Page 973 of 1449
REAR AXLE -Rear Hub Assembly27B-27
INSPECTION
WHEEL BEARING ROTATION STARTING TORQUE
CHECK
1. Tighten special tools in rear hub assembly to the specified
torque.
2. Hold rear hub assembly in a vice by way of wooden
block.
3. Measure the wheel bearing rotation torque with special
tools.
Limit: 1.0 N
·m
4. Hub rotation starting torque must be under the limit value
and there should be no stickiness or roughness when
rotating the hub.
WHEEL BEARING AXIAL PLAY CHECK
1. Check the wheel bearing axial play.
Limit: 0.05 mm
2. If the wheel bearing axial play exceeds the limit value
at the specified torque of (225±25 N
·m), replace the
rear hub assembly.
Wooden
block
MB991000
(MB990998)MB991017
225±25 N·m
MB990326
Wooden
block
Wooden
block
Page 983 of 1449
REAR AXLE -Differential Carrier 27B-37
BUSHING REPLACEMENT
1. Remove and press fit the bush with special tool. (About
removal and press fitting the bush of the differential
support arm, refer to P. 27B-57.)
2. Press fit the bush so that the hollow of the bush is on
the position shown as the illustration.
3. Press fill the bush until the surface of the outer sleeve
of the bush, differential mounting bracket.
MB990641 Bush
Differential
mount
bracket
Steel block
Hollow