Jeep 1997 Grand Cherokee Service Manual page 112

3 - 54 DIFFERENTIAL AND DRIVELINE
DIAGNOSIS AND TESTING (Continued)
CONDITION
WHEEL NOISE
AXLE SHAFT NOISE
AXLE SHAFT BROKE
DIFFERENTIAL CASE
CRACKED
DIFFERENTIAL
GEARS SCORED
LOSS OF LUBRICANT
POSSIBLE CAUSES
1. Wheel loose.
2. Faulty, brinelled wheel bearing.
1. Misaligned axle shaft tube.
2. Bent or sprung axle shaft.
3. End play in drive pinion bearings.
4. Excessive gear backlash between ring
gear and pinion gear.
5. Improper adjustment of drive pinion gear
shaft bearings.
6. Loose drive pinion gearshaft yoke nut.
7. Improper wheel bearing adjustment.
8. Scuffed gear tooth contact surfaces.
1. Misaligned axle shaft tube.
2. Vehicle overloaded.
3. Erratic clutch operation.
4. Grabbing clutch.
1. Improper adjustment of differential
bearings.
2. Excessive ring gear backlash.
3. Vehicle overloaded.
4. Erratic clutch operation.
1. Insufficient lubrication.
2. Improper grade of lubricant.
3. Excessive spinning of one wheel/tire.
1. Lubricant level too high.
CORRECTION
1. Tighten loose nuts.
2. Faulty or brinelled bearings must be
replaced.
1. Inspect axle shaft tube alignment. Correct
as necessary.
2. Replace bent or sprung axle shaft.
3. Refer to Drive Pinion Bearing Pre-Load
Adjustment.
4. Check adjustment of ring gear backlash
and pinion gear. Correct as necessary.
5. Adjust drive pinion shaft bearings.
6. Tighten drive pinion gearshaft yoke nut
with specified torque.
7. Readjust as necessary.
8. If necessary, replace scuffed gears.
1. Replace broken axle shaft after correcting
axle shaft tube alignment.
2. Replace broken axle shaft. Avoid
excessive weight on vehicle.
3. Replace broken axle shaft after inspecting
for other possible casues. Avoid erratic use
of clutch.
4. Replace broken axle shaft. Inspect clutch
and make necessary repairs or adjustments.
1. Replace cracked case; examine gears and
bearings for possible damage. At reassembly,
adjust differential bearings properly.
2. Replace cracked case; examine gears and
bearings for possible damage. At reassembly,
adjust ring gear backlash properly.
3. Replace cracked case; examine gears and
bearings for possible damage. Avoid
excessive weight on vehicle.
4. Replace cracked case. After inspecting for
other possible causes, examine gears and
bearings for possible damage. Avoid erratic
use of clutch.
1. Replace scored gears. Scoring marks on
the drive face of gear teeth or in the bore are
caused by instantaneous fusing of the mating
surfaces. Scored gears should be replaced.
Fill rear differential housing to required
capacity with proper lubricant. Refer to
Specifications.
2. Replace scored gears. Inspect all gears
and bearings for possible damage. Clean and
refill differential housing to required capacity
with proper lubricant.
3. Replace scored gears. Inspect all gears,
pinion bores and shaft for damage. Service
as necessary.
1. Drain excess lubricant by removing fill plug
and allow lubricant to level at lower edge of
fill plug hole.
ZG