Mitsubishi Montero Sport (2004+). Manual - part 426

REAR AXLE DIAGNOSIS

TSB Revision

REAR AXLE

27-5

INSPECTION PROCEDURE 4: Gear Noise while Driving <Conventional Differential>

DIAGNOSIS

STEP 1. 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 API 
classification GL-5 or higher; Above 

−23°C(−10°F): 

SAE 90, 85W-90, 80W-90,  From 

−34 to −23°C(−30 to 

−10°F): SAE 80W, 80W-90,  Below −34°C(−30°F): 

SAE 75W.  Then go to Step 6.

NO :  Go to Step 2.

STEP 2. Check the gear engagement.
Q: Is the gear engagement in good condition?

YES : Go to Step 3.
NO :  Adjust or replace the part. Then go to Step 6.

STEP 3. Check the drive pinion turning torque.
Q: Is the drive pinion turning torque correct?

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

STEP 4. Check the gear for damage.
Q: Is the gear damaged?

YES : Replace the gear. Then go to Step 6.
NO :  Go to Step 5.

STEP 5. Check for foreign material.
Q: Is foreign material found?

YES : Remove the foreign material and then inspect. If 

necessary, replace the part. Then go to Step 6.

NO :  Go to Step 6.

STEP 6. 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

27-6

INSPECTION PROCEDURE 5: Gear Noise while Coasting <Conventional Differential>

DIAGNOSIS

STEP 1. Check the drive pinion turning torque.

Q: Is the drive pinion turning torque correct?

YES : 

Go to Step 2.

NO : 

Adjust the turning torque. Then go to Step 3.

STEP 2. Check the gear for damage.

Q: Is the gear damaged?

YES : 

Replace the gear. Then go to Step 3.

NO : 

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 6: Bearing Noise while Driving or Coasting <Conventional Differential>

DIAGNOSIS

STEP 1. Check the drive pinion rear bearing for 
cracks or damage.

Q: Is the drive pinion rear bearing cracked or 

damaged?

YES : 

Replace the part. Then go to Step 2.

NO : 

Go to Step 2.

STEP 2. Retest the system.

Q: Is the abnormal noise eliminated?

YES : 

The procedure is complete.

NO : 

Start over at Step 1.

INSPECTION PROCEDURE 7: Noise while Turning <Conventional Differential>

DIAGNOSIS

STEP 1. Check the side bearing for wear or 
damage.

Q: Is the side bearing worn or damaged?

YES : 

Replace the part. Then go to Step 3.

NO : 

Go to Step 2.

STEP 2. Check the side gear, pinion gear or 
pinion shaft for damage.

Q: Is the side gear, pinion gear or pinion shaft 

damaged?

YES : 

Replace the part. Then go to Step 3.

NO : 

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.

REAR AXLE DIAGNOSIS

TSB Revision

REAR AXLE

27-7

INSPECTION PROCEDURE 8: Heat <Conventional Differential>

DIAGNOSIS

STEP 1. 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 API 
classification GL-5 or higher; Above 

−23°C(−10°F): 

SAE 90, 85W-90, 80W-90,  From 

−34 to −23°C(−30 to 

−10°F): SAE 80W, 80W-90,  Below −34°C(−30°F): 

SAE 75W.  Then go to Step 3.

NO :  Go to Step 2.

STEP 2. Check the gear backlash (excessive). Refer to 
GROUP 26, Differential Carrier 

− Inspection Before 

Disassembly 

P.26-41

.

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 heat 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

27-8

INSPECTION PROCEDURE 9: Oil Leakage <Conventional Differential>

DIAGNOSIS

STEP 1. Check the breather hose for clogging.
Q: Is the breather hose clogged?

YES : Clean or replace the part. Then go to Step 5.
NO :  Go to Step 2.

STEP 2. Check the cover installation.
Q: Is the cover installed correctly?

YES : Go to Step 3.
NO :  Repair. Then go to Step 5.

STEP 3. Check the oil seal for wear or damaged.
Q: Is the oil seal worn or damaged?

YES : Replace the seal. Then go to Step 5.
NO :  Go to Step 4.

STEP 4. 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 : Refill Hypoid gear oil API classification GL-5 or 

higher; Above 

−23°C(−10°F): SAE 90, 85W-90, 

80W-90,  From 

−34 to −23°C(−30 to −10°F): SAE 

80W, 80W-90,  Below 

−34°C(−30°F): SAE 75W.  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.

INSPECTION PROCEDURE 10: Abnormal Noise during Driving or Shifting <Limited-Slip Differential>

NOTE: In addition to a malfunction of the differential carrier components, abnormal noise can also be caused 
by the universal joint of the propeller shaft, the drive shafts, the wheel bearings, etc. Before disassembling 
any parts, take all possibilities into consideration and confirm the source of the noise.

DIAGNOSIS

STEP 1. Check for looseness in the companion 
flange tightening nut.

Q: Is there looseness in the companion flange 

tightening nut?

YES : 

Tighten to 216 N

⋅m (159 ft-lb). Then go to 

Step 3.

NO : 

Go to Step 2.

ACX01083 AC

8 mm (0.3 in)

UPPER
LIMIT

LOWER
LIMIT