Mitsubishi Montero Sport (2004+). Manual - part 427

REAR AXLE DIAGNOSIS

TSB Revision

REAR AXLE

27-9

STEP 2. Check the drive gear backlash 
(excessive).

Q: Is the gear backlash correct?

YES : 

Go to Step 3.

NO : 

Adjust the backlash. Then go to Step 3.

STEP 3. Retest the system.

Q: Is the abnormal noise eliminated?

YES : 

The procedure is complete.

NO : 

Start over at Step 1.

INSPECTION PROCEDURE 11: Abnormal Noise when Cornering <Limited-Slip Differential>

DIAGNOSIS

STEP 1. Check that Hypoid gear oil MITSUBISHI Genuine 
Gear Oil Part No.8149630 EX or equivalent is being used.
Q: Is the Hypoid gear oil MITSUBISHI Genuine Gear Oil 

Part No.8149630 EX or equivalent being used?
YES : Go to Step 2.
NO :  Replace the oil. Then go to Step 4.

STEP 2. Check the oil level.

Remove the filler plug and check the gear oil level.
Q: Is the gear oil level more than 8 mm (0.3 inch) below the 

bottom of the filler plug hole?
YES : Check the oil leakage from differential carrier, and 

repair if necessary. Then refill Hypoid gear oil 
MITSUBISHI Genuine Gear Oil Part No.8149630 EX 
or equivalent. Then go to Step 4.

NO :  Go to Step 3.

STEP 3. Check the limited slip differential case assembly 
for damage.
Q: Is the limited slip differential case assembly damaged?

YES : Replace the part. Then go to Step 4.
NO :  Go to Step 4.

STEP 4. Retest the system.
Q: Is the abnormal noise eliminated?

YES : The procedure is complete.
NO :  Start over at Step 1.

ACX01083 AC

8 mm (0.3 in)

UPPER
LIMIT

LOWER
LIMIT

REAR AXLE DIAGNOSIS

TSB Revision

REAR AXLE

27-10

INSPECTION PROCEDURE 12: Gear Noise <Limited-Slip Differential>

NOTE: Noise from the engine, muffler vibration, transmission, propeller shaft, wheel bearings, tires, body, 
etc., is easily mistaken as being caused by malfunction in the differential carrier components. Be extremely 
careful and attentive when test driving, etc.
Test methods to confirm the source of the abnormal noise include: coasting, acceleration, constant speed 
driving, raising the rear wheels, etc. Use the method most appropriate to the circumstances.

DIAGNOSIS

STEP 1. Check that Hypoid gear oil MITSUBISHI Genuin 
Gear Oil Part No.8149630 EX or equivalent is being used.
Q: Is the Hypoid gear oil MITSUBISHI Genuine Gear Oil 

Part No.8149630 EX or equivalent being used?
YES : Go to Step 2.
NO :  Replace the oil. Then go to Step 9.

STEP 2. Check the oil level.

Remove the filler plug and check the gear oil level.
Q: Is the gear oil level more than 8 mm (0.3 inch) below the 

bottom of the filler plug hole?
YES : Check the oil leakage from differential carrier, and 

repair if necessary. Then refill Hypoid gear oil 
MITSUBISHI Genuine Gear Oil Part No.8149630 EX 
or equivalent. Then go to Step 9.

NO :  Go to Step 3.

STEP 3. Check the tooth contact (engagement) of the drive 
gear. Refer to GROUP 26, Differential Carrier 

− Inspection 

Before Disassembly 

P.26-41

.

Q: Is the tooth contact (engagement) of the drive gear 

correct?
YES : Go to Step 4.
NO :  Adjust or replace the part. Then go to Step 9.

STEP 4. Check the drive gear backlash.
Q: Is the drive gear backlash correct?

YES : Go to Step 5.
NO :  Adjust the backlash. Then go to Step 9.

STEP 5. Check the drive pinion turning torque.
Q: Is the drive pinion turning torque correct?

YES : Go to Step 6.
NO :  Adjust the turning torque. Then go to Step 9.

ACX01083 AC

8 mm (0.3 in)

UPPER
LIMIT

LOWER
LIMIT

REAR AXLE DIAGNOSIS

TSB Revision

REAR AXLE

27-11

STEP 6. Check the drive gear and drive pinion for tooth 
damage or breakage.
Q: Are the drive gear and drive pinion for tooth damaged?

YES : Replace the part. Then go to Step 9.
NO :  Go to Step 7.

STEP 7. Check the drive pinion bearing and side bearing 
for seizure, damage or breakage.
Q: Are the drive pinion bearing and side bearing damaged?

YES : Replace the part. Then go to Step 9.
NO :  Go to Step 8.

STEP 8. Check the limited slip differential case assembly 
for damage.
Q: Is the limited slip differential case assembly damaged?

YES : Replace the part. Then go to Step 9.
NO :  Go to Step 9.

STEP 9. Retest the system.
Q: Is the gear noise eliminated?

YES : The procedure is complete.
NO :  Start over at Step 1.

INSPECTION PROCEDURE 13: Gear Oil Leakage <Limited-Slip Differential>

DIAGNOSIS

STEP 1. Check for looseness in the filler or drain 
plug.

Q: Is the filler or drain plug loose?

YES : 

Tighten the filler plug to 49 N

⋅m (36 ft-lb) or 

tighten the drain plug to 59 N

⋅m (44 ft-lb). 

Then go to Step 5.

NO : 

Go to Step 2.

STEP 2. Check the breather hose for clogging or 
damage.

Q: Is the breather hose clogged or damaged?

YES : 

Clean or replace the part. Then go to Step 

5.

NO : 

Go to Step 3.

STEP 3. Check for looseness in the companion 
flange tightening nut.

Q: Is the companion flange tightening nut loose?

YES : 

Tighten to 216 N

⋅m (159 ft-lb). Then go to 

Step 5.

NO : 

Go to Step 4.

STEP 4. Check the oil seal for wear, damage or 
foreign material.

Q: Is the oil seal worn, damaged or does it contain 

foreign material?

YES : 

Replace the seal. Then go to Step 5.

NO : 

Go to Step 5.

STEP 5. Retest the system.

Q: Is there oil leakage?

YES : 

Start over at Step 1.

NO : 

The procedure is complete.

REAR AXLE DIAGNOSIS

TSB Revision

REAR AXLE

27-12

INSPECTION PROCEDURE 14: Seizure <Limited-Slip Differential>

NOTE: In the event of seizure, disassemble and replace the parts involved. Be sure to check all components 
for any irregularities and repair or replace as necessary.

DIAGNOSIS

STEP 1. Check that Hypoid gear oil MITSUBISHI Genuine 
Gear Oil Part No.8149630 EX or equivalent is being used.
Q: Is Hypoid gear oil MITSUBISHI Genuine Gear Oil Part 

No.8149630 EX or equivalent being used?
YES : Go to Step 2.
NO :  Replace the oil. Then go to Step 6.

STEP 2. Check the oil level.

Remove the filler plug and check the gear oil level.
Q: Is the gear oil level more than 8 mm (0.3 inch) below the 

bottom of the filler plug hole?
YES : Check the oil leakage from differential carrier, and 

repair if necessary. Then refill with Hypoid gear oil 
MITSUBISHI Genuine Gear Oil Part No.8149630 EX 
or equivalent. Then go to Step 6.

NO :  Go to Step 3.

STEP 3. Check the drive gear backlash (low).
Q: Is the drive gear backlash correct?

YES : Go to Step 4.
NO :  Adjust the backlash. Then go to Step 6.

STEP 4. Check the drive pinion turning torque (excessive).
Q: Is the drive pinion turning torque correct?

YES : Go to Step 5.
NO :  Adjust it. Then go to Step 6.

STEP 5. Check the side bearing preload (excessive).
Q: Are the side bearing cap mounting bolts tightened to 69 

− 78 N⋅m (51- 58 ft-lb)?
YES : Go to Step 6.
NO :  Tighten them to 69 

− 78 N⋅m (51 − 58 ft-lb). Then go 

to Step 6.

STEP 6. Retest the system.
Q: Does the seizure still occur?

YES : Start over at Step 1.
NO :  The procedure is complete.

ACX01083 AC

8 mm (0.3 in)

UPPER
LIMIT

LOWER
LIMIT