1998 MITSUBISHI LANCER EVOLUTION IV differential

27-1
REAR AXLE
CONTENTS
SERVICE SPECIFICATIONS 2. . . . . . . . . . . . . .
LUBRICANT 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SEALANT 2. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPECIAL TOOLS 3. . . . . . . . . . . . . . . . . . . . . . . .
TROUBLESHOOTING 5. . . . . . . . . . . . .
ON-VEHICLE SERVICE
27. . . . . . . . . . . . . . .
1. Rear Axle Total Backlash Check 27. . . . . . .
2. Gear Oil Level Check 27. . . . . . . . . . . . . . . .
3. Gear Oil Change 28. . . . . . . . . . . . . . . . . . . . .
4. Fluid Level Check 29. . . . . . . . . . . . . . . . . . . .
5. Bleeding 29. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6. Differential Carrier Oil Seal
Replacement 30. . . . . . . . . . . . . . . . . . . . . . . . .
7. Speed Sensor Output Voltage
Measurement 31.
8. Action When Battery Runs Out 32. . . . . . . .
REAR HUB ASSEMBLY 33. . . . . . . . . . . . . . . .
KNUCKLE 35. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DRIVE SHAFT 36. . . . . . . . . . . . . . . . . . . . . . . . .
DIFFERENTIAL CARRIER
39.
DIFFERENTIAL CARRIER
41. . . . . . . . . . . . . . . . . . .
TORQUE TRANSFER DIFFERENTIAL
43. . . . . . . . . . . . . . .
LSD CASE ASSEMBLY
46. . . . . . . . . . .
HYDRAULIC UNIT
50. . . . . . . . . . . . . . .
SENSOR RELAY
52. . . . . . . . . . . . . . .
AYC-ECU 53. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

REAR AXLE – Service Specifications / Lubricant / Sealant27-2
SERVICE SPECIFICATIONS

ItemsStandard valueLimit
Rear axle total backlash mm–5
Pressure generated by hydraulic unit MPa {kgf/cm2}0 – 1.6 {10.0 – 16.0}–
Wheel bearing axial play mm–0.05
Wheel bearing rotation starting torque Nm {kgf
cm}–1.0 {10.5} or less

ItemsStandard valueLimit
Right-to-left difference in combined thickness of friction plate and fric-
tion disc mm0 – 0.05–
Clearance between spring plate and differential case mm0.06 – 0.25–
LSD differential torque
Nm {kgf
m}
When new clutch plate is installed5 – 19 {0.5 – 1.9}–
Nm {kgf
m}
When existing clutch plate is installed2 – 19 {0.2 – 1.9}–
Distortion of friction plate and friction disc mm–0.08
Difference in thickness between friction plate, friction disc, and spring
plate mm–0.1
LUBRICANT

ItemsSpecified lubricantCapacity
Gear oilTorque
transfer
differential
DifferentialMITSUBISHI GENUINE DIA QUEEN SUPER
HYPOID GEAR OIL (GL-5)0.41 ± 0.02 dm3
{0.41 ± 0.02 }
differentialTorque transfer
mechanismMITSUBISHI GENUINE DIA QUEEN AYC FLUID0.700
0.05dm3
{0.700
0.05}
Hydraulic piping fluidMITSUBISHI GENUINE DIA QUEEN ATF-SPII1 dm3 {1 }
Torque transfer mechanism oil seal lipsVaselineAs required
SEALANT

ItemsSpecified sealant
Torque transfer differential vent plugSemi-drying sealant: THREEBOND 1281B (460 g)
Torque transfer mechanism cover

REAR AXLE – Special Tools27-3
SPECIAL TOOLS
ToolNumberNameUse
MB991529Diagnosis code
check harnessInspection of AYC (diagnosis display by AYC
warning lamp)
MD998330
(MD998331)Oil pressure
gauge
(2,942 kPa
{30 kgf/cm
2})
Hydraulic pressure measurement with AYC>
MB991705Hose adapter
MB990925Bearing & oil seal
installer setPressfitting of oil seal
MB991115Oil seal installerPressfitting of oil seal (used in
combination with MB990938)
MD998812Installer capPressfitting of oil seal nism of vehicles with AYC>
MD998813Installer 100
MD998829Installer adapter
(60)
MB990767End yoke holderFixing of hub

REAR AXLE – Special Tools27-4
Tool UseName Number
AB
MB990241
A: MB990242
B: MB990244Rear axle shaft
puller
A: Puller shaft
B: Puller bar
Removal of drive shaft

Removal of rear hub assembly
MB991354Puller body
A: MB991017
B: MB990998
C: MB991000A, B: Front hub
remover &
installer
C: Spacer
Temporary fixing of unit bearing

Measurement of wheel bearing rotation
starting torque

Measurement of wheel bearing axial play
Use MB991000 (component
of MB990998) for the spacer.
MB990326Preload socket
Measurement of wheel bearing rotation
starting torque

Measurement of drive pinion preload
MB991406,
MB990635, or
MB991113Steering linkage
puller
Disconnection of ball joint

Removal of hub bolt
MB991460PlugPrevention of differential oil from being dis-
charged and entry of foreign matter tial>
MB990988Side gear holding
tool setMeasurement of clutch plate preload without AYC>
MB990850End yoke holderRemoval and installation of companion flange

REAR AXLE – Troubleshooting 27-22
INSPECTION PROCEDURE 2
AYC warning lamp remains lit up after the engine has
started.
Probable cause
The AYC warning lamp ON circuit is probably short-circuited.
Defective combination meter

Defective harness (short-circuit)

Defective AYC-ECU
NOTE
This symptom is limited only when AYC-ECU power supply is in normal condition and the diagnosis
code is correct.
OK
Replace combination meter.
NO
Check the harness between AYC
warning lamp and AYC-ECU.NG
Repair
Does the AYC warning lamp goes out
when the B-96 AYC-ECU connector
is disconnected?YESReplace AYC-ECU.
INSPECTION PROCEDURE 3
AYC is inoperative.
Unable to start or accelerate on slippery road surfaces.
Probable cause
The hydraulic oil level is probably low, there is an oil leak, the hydraulic unit is defective,
or the torque transfer differential is defective.
Low hydraulic oil level

Oil leak

Defective hydraulic unit

Defective torque transfer differential
NOTE
This symptom is limited only when the diagnosis code is correct.
NG
Replace the hydraulic unit.
NG
Replace the torque transfer differential.
Check the trouble symptom.
NG
Replace AYC fluid.
OK
Correct
Check the trouble symptom.NO
Replace the torque transfer differential.
OK
Is foreign matter trapped in the hydrau-
lic line?YES
Repair
OK
Check the AYC for operation.OKCheck the AYC fluid.
NG
Add hydraulic oil.
NG
Check hydraulic pressure.NGBleed the system of air.
Check the hydraulic oil level.NGCheck for oil leak.OK
Repair

REAR AXLE – Troubleshooting 27-23
INSPECTION PROCEDURE 4
Rear tires are noisy during low-speed cornering.
Probable cause
The hydraulic unit or torque transfer differential is probably defective.
Defective hydraulic unit

Defective torque transfer differential
NOTE
This symptom is limited only when the diagnosis code is correct.
NG
Replace the hydraulic unit.
NG
Replace the torque transfer differential.
Check the trouble symptom.
NG
Replace AYC fluid.
OK
Correct
Check the trouble symptom.NO
Replace the torque transfer differential.
OK
Is foreign matter trapped in the hydrau-
lic line?YES
Repair
Check the AYC for operation.OKCheck the AYC fluid.
NG
Check hydraulic pressure.NGBleed the system of air.

REAR AXLE – On-vehicle Service 27-27
ON-VEHICLE SERVICE

1. REAR AXLE TOTAL BACKLASH CHECK
If the drive system roars or the vehicle vibrates, use the
following procedure to measure total backlash in the rear
axle. Based on the measurement taken, determine whether
the differential carrier assembly needs to be removed or not.
(1) Place the shift lever in the neutral position and operate
the parking brake.
(2) Turn the propeller shaft fully clockwise and make an
alignment mark on the companion flange dust cover and
gear carrier.
(3) Turn the propeller shaft fully counterclockwise and
measure the deviation between the alignment marks.
Limit: 5 mm
(4) If the backlash exceeds the limit, replace the differential
carrier assembly.
2. GEAR OIL LEVEL CHECK
2-1 DIFFERENTIAL
(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.
Standard value (A): 6 mm
(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:
MITSUBISHI GENUINE DIA QUEEN SUPER
HYPOID GEAR OIL (GL-5)
NOTE
10
C or more: #90, less than 10
C: #80
(4) Fit the filler plug and tighten it to the specified torque.
Alignment marks
Filler plug
49 Nm
{5.0 kgf
m}
Gear oil
Upper
limit
Lower
limit

REAR AXLE – On-vehicle Service 27-28
2-2 TORQUE TRANSFER MECHANISM
(1) Remove the filler plug.
(2) Check that the gear oil level is up to the bottom end
of the filler plug hole.
(3) If the gear oil level is lower than the bottom end of the
filler plug hole, add the specified gear oil up to the bottom
end of the filler plug hole.
Specified gear oil:
MITSUBISHI GENUINE DIA QUEEN SUPER AYC
FLUID
(4) Fit the filler plug and tighten it to the specified torque.
3. GEAR OIL CHANGE
3-1 DIFFERENTIAL
(1) Remove the drain plug to discharge the gear oil.
(2) Fit the drain plug and tighten it to the specified torque.
Tightening torque: 49 Nm {5.0 kgf
m}
(3) Remove the filler plug and add the specified gear oil
up to the bottom end of the filler plug hole.
Specified gear oil:
MITSUBISHI GENUINE DIA QUEEN SUPER
HYPOID GEAR OIL (GL-5)
Quantity used: 0.41 ± 0.02 dm
3 {0.41 ± 0.02 }
NOTE
10
C or more: #90, less than 10
C: #80
(4) Fit the filler plug and tighten it to the specified torque.
Filler plug
49 Nm {5.0 kgf
m}
Gear oil
Filler plug
49 Nm
{5.0 kgf
m}
Gear oil
Drain plug