Page 950 of 1449

REAR AXLE -Lubricants/Sealants/Special tools27B-4
ItemQuantity Specified lubricants
Vehicles with
ACDand
Hydraulic piping fluidATF-SP™1L
ACDand
AY CTorque transfer mechanism oil
seal lipsVaselineAs required
B.J. jointRepair kit grease85±10 g
T.J. jointRepair kit grease105±10 g
SEALANTS
ItemsSpecified sealantsRemarks
Vehicles with me-
chanicalLSD
Vent plug3M ATD Part No. 8661, 8663 or
equivalent
Semi-drying sealant
chanicalLSD
Differential cover assembly
equivalent
Vehicles with ACD
andAYC
Vent plug
andAYC
Differential carrier cover
mounting part
Vehicles with me-
chanical LSDDrive gear and differential
case mounting part3M Stud Locking 4170 or equivalentAnaerobic sealant
SPECIAL TOOLS
ToolNumberNameUse
MB991502MUT-IIsub as-
semblyInspection of AYC (diagnosis display by
MUT-II)
MB991529Diagnosis code
check harnessInspection of AYC
(diagnosis display by ACD mode indicator
lamp)
MD998330
(MD998331)Oil pressure gaugeHydraulic pressure measurement
with AYC>
MB991705Hose adapter
MB990925Bearing and oil
seal installer setRemoval of wheel bearing
Page 951 of 1449
REAR AXLE -Special Tools27B-5
Tool UseName Number
MB991115Oil seal installerPress-fitting of oil seal
(AYC differential: used in combination with
MB990938)
MD998812Installer capPress-fitting of oil seal
(torque transfer mechanism of vehicles with
AYC)
MD998813Installer100
MD998829Installer adapter
(60)
MB990767Front hub and
flange yoke holderRemoval, installation of the drive shaft nut
A
B
MB990241
A: MB990242
B: MB990244Rear axle shaft
puller
A:Puller shaft
B:Puller barDRemoval of drive shaft
DRemoval of rear hub assembly
MB991354Puller body
A
CB
00005697
A: MB991017
B: MB990998
C: MB991000A,B: Front hub re-
mover and in-
staller
C: SpacerDTemporary fixing of wheel bearing
DMeasurement of wheel bearing rotation
starting torque
DMeasurement of wheel bearing axial play
Use MB991000 (component of MB990998)
for the spacer.
Page 952 of 1449
REAR AXLE -Special Tools27B-6
ToolNumberNameUse
MB990685Torque wrenchMeasurement of the starting torque of wheel
bearing
MB990326Preload socket
MB991113 or
MB990635Steering linkage
pullerDisconnection of ball joint
MB990641Lower arm bush
(A) remover & in-
stallerRemoval and press-fitting of differential
support member bush
MB991439Bush remover &
installerRemoval and press-fitting of differential
support arm bush
MB991460PlugPrevention of differential oil from being
discharged and entry of foreign matter
differential>
MB990909Working baseSupporting of the differential carrier
MB991116AdapterSupport of differential carrier assembly
MB990810Side bearing pullerDRemoval of the side bearing inner race
DRemoval of the companion flange
Page 954 of 1449

REAR AXLE -Special Tools/Troubleshooting 27B-8
NumberNameO.D.mm
BoxMB990551Box–
CBaseMB990989Base–
ABCBase
MB990990Tool A25A
Tool
MB990991Tool B28
ToolMB990992Tool C31
Installer adapterBrass bar
Bar (one-touch type) AB
C
Toolbox
Tool numberO.D.mmTool numberO.D.mm
AMB99092639AMB99093363.5
MB99092745MB99093467.5
MB99092849.5MB99093571.5
MB99092951MB99093675.5
MB99093054MB99093779
MB99093157BMB990938-
MB99093261CMB990939-
TROUBLESHOOTING
BASIC TROUBLESHOOTING CONDITIONS
Refer to GROUP 00 – How to Use Troubleshooting/Inspection Service Points.
NOTE
Before starting the troubleshooting procedure, make sure that the following items have been checked
okay.
DThe correct steering wheel has been properly installed in the neutral position of the steering column
shaft.
DTire and wheel sizes are correct with correct specifications. Inflation pressure, balance, and wear
conditions are okay.
DWheel alignment is correct.
DThe engine, suspension, and other parts have not been remodeled so as to affect the AYC system.
DIAGNOSIS FUNCTION
READING THE DIAGNOSIS CODES
Read the diagnosis code using MUT-IIor ACD mode indicator
lamp. (Refer to GROUP 00 – How to Use Troubleshooting/
Inspection Service Points.)
NOTE
Connect the MUT-IIto the 16-pin diagnosis connector.
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 961 of 1449

REAR AXLE -Troubleshooting 27B-15
INSPECTION PROCEDURE 6
Rear tires are noisy during low-speed cornering.
Vehicle skews.
Probable cause
The hydraulic unit or torque transfer differential is probably defective.DDefective hydraulic unit
DDefective torque transfer differential
NOTE
This symptom is limited only when the diagnosis code is correct.
NG
Replace the hydraulic unit. (Refer to
P.27B-61.)
NG
Add fluid. (Refer to P.27B-19.)
OKRepair
Check the trouble symptom.NO
Replace the torque transfer differential.
OK
Is foreign matter trapped in the hydrau-
lic line?YES
Repair
Check the fluid level.
(Refer to P.27B-19.)Check the hydraulic pressure line for
leak.
OK
Check hydraulic pressure.
(Refer to P.27-21.)NGBleed the system of air.
(Refer to P.27-19.)
Check the AYC for operation.
(Refer to P.27B-20.)Check the trouble symptom. OK
NG
NGNG
INSPECTION PROCEDURE 7
Noise is produced from the torque transfer differential
during turning
Probable cause
The torque transfer differential is probably defective.DDefective torque transfer differential
NOTE
This symptom is limited only when the diagnosis code is correct.
NG
Replace the gear oil of the torque transfer differential. (Refer to
P.27B-17.)
Replace the gear oil of the torque transfer differential. (Refer to
P.27B-17.)Normal
Replace the gear oil of the torque transfer differential. (Refer to
P.27B-17.)
Replace the torque transfer differential.
Check the trouble symptom.
OKNG
NG
MUT-IIActuator test
DNo. 06 Clutch operation check (left side) 5 times
DNo. 07 Clutch operation check (right side) 5 times
DSteering wheel on neutral position
DDrive straight in 20 km/h or less
MUT-IIActuator test
DNo. 06 Clutch operation check (left side) 5 times
DNo. 07 Clutch operation check (right side) 5 times
DSteering wheel on neutral position
DDrive straight in 20 km/h or less
Check the trouble symptom.
Normal
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