Notice: It is very important that tooth contact be tested after the differential
is taken apart. Variations in the differential or differential drive pinion
gear inner bearing may cause the differential drive pinion gear to be too
far away from, or close to, the differential ring gear. Therefore, the tooth
contact pattern must be tested and corrected, (if necessary) to prevent gear
noise.
- Clean all of the dirt from the area of the rear axle housing
cover before removing the rear axle housing cover.
- Remove the rear axle housing cover. Refer to
Rear Axle Housing Cover and Gasket Replacement
.
- Wipe the oil out of the rear axle housing.
- Carefully clean each tooth of the ring gear.
- Install the J 39446
to the speed sensor reluctor wheel on vehicles not equipped with traction
control rear axles.
- Using a medium stiff brush, apply a mixture of gear marking compound
sparingly to all of the ring gear teeth. The area of tooth contact of the
differential drive pinion gear should remain visible.
Notice: Use the correct fastener in the correct location. Replacement fasteners
must be the correct part number for that application. Fasteners requiring
replacement or fasteners requiring the use of thread locking compound or sealant
are identified in the service procedure. Do not use paints, lubricants, or
corrosion inhibitors on fasteners or fastener joint surfaces unless specified.
These coatings affect fastener torque and joint clamping force and may damage
the fastener. Use the correct tightening sequence and specifications when
installing fasteners in order to avoid damage to parts and systems.
- Tighten the differential carrier bearing cap bolts/screws.
Tighten
Tighten the differential carrier bearing cap bolts/screw to 75 N·m
(55 lb ft).
Important: A test made without properly loading the gears will not give a satisfactory
pattern.
- Apply the park brake until a torque of 14 N·m (10 lb ft)
is required in order to rotate the drive pinion gear.
- Use the following procedure in order to obtain a ring gear tooth
contact pattern:
9.1. | Using a wrench on the pinion gear yoke, rotate the assembly through
three complete revolutions of the ring gear. |
9.2. | Using a wrench on the pinion gear yoke, rotate the
assembly through three complete revolutions of the ring gear in the opposite
direction. |
- Inspect the differential
ring gear teeth for a tooth contact pattern (1).
- The pattern is acceptable if the area of differential drive pinion
gear contact (1) remains in the center of the differential ring gear
tooth. If the pattern is not acceptable, proceed to Step 14.
- If the differential ring gear tooth pattern is acceptable, remove
theJ 39446
.
- Install the rear axle housing cover. Refer to
Rear Axle Housing Cover and Gasket Replacement
.
- Inspect the differential
ring gear teeth for a low flank contact pattern (2).
- If this contact pattern exists, repair the low flank contact
by decreasing the shim thickness of the bearing on the differential drive
pinion gear. This moves the smaller diameter of the contact (2) out
toward the center line (1) of the differential ring gear.
- Remove the J 39446
.
- Install the rear axle housing cover. Refer to
Rear Axle Housing Cover and Gasket Replacement
.
- Inspect the differential
ring gear teeth for a heel contact pattern (1).
- If this contact pattern exists, repair the heel contact by decreasing
the backlash. Refer to
Backlash Adjustment
.
- Remove the J 39446
.
- Install the rear axle housing cover. Refer to
Rear Axle Housing Cover and Gasket Replacement
.
- Inspect the differential
ring gear teeth for a high face contact pattern (2).
- If this contact pattern exists, repair the high face contact
by increasing the thickness of the bearing shim of the differential drive
pinion gear. This moves the area of differential drive pinion gear contact
out toward the differential ring gear center line (1).
- Remove the J 39446
.
- Install the rear axle housing cover. Refer to
Rear Axle Housing Cover and Gasket Replacement
.
- Inspect the differential
ring gear teeth for a toe contact pattern (1).
- If this contact pattern (1) exists repair the heel contact
by Increasing the backlash. This moves the area of differential drive pinion
gear contact toward the heel.
- Remove the J 39446
.
- Install the rear axle housing cover. Refer to
Rear Axle Housing Cover and Gasket Replacement
.