Tooth Contact Pattern Test

Standard Rear Axle Assembly:

Rear Axle Assembly With Traction Control (Acceleration Slip Regulation):

^ Tool Required:
- J 39446 ABS Exciter Ring Protector Kit

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.

NOTICE: Always use the correct fastener in the correct location. When you replace a fastener, use ONLY the exact part number for that application. The manufacturer will call out those fasteners that require a replacement after removal. The manufacturer will also call out the fasteners that require thread lockers or thread sealant. UNLESS OTHER WISE SPECIFIED, do not use supplemental coatings (paints, greases, or other corrosion inhibitors) on the threaded fasteners or fastener joint interfaces. Generally, such coatings adversely affect the fastener torque and the joint clamping force, and may damage the fastener. When you install fasteners, use the correct tightening sequence and specifications. Following these instructions can help you avoid damage to parts and systems.

CLEAN
1. All dirt from area of rear axle housing cover (43) before Removing.
2. Remove rear axle housing cover.
3. Wipe oil out of the housing (16) and carefully clean each tooth of the ring gear (20).
4. Select correct exciter ring protector from J 39446 and attach to speed sensor reluctor wheel (39) on vehicles with non-traction control rear axles only.
5. Use gear marking compound, and apply a mixture sparingly to all ring gear teeth, using a medium stiff brush. When properly used, the area of differential drive pinion gear tooth contact will be visible when hand load is applied.
- Tighten Differential carrier bearing cap bolts/screws (26) to 75 Nm (55 ft. lbs.).
6. Apply park brake until a torque of 54 to 70 Nm (40 to 52 ft. lbs.) is required to turn drive pinion gear (23).

Important: A test made without loading the gears will not give a satisfactory pattern. Turn pinion gear yoke (3) with a wrench so that ring gear (20) rotates one full revolution. Reverse rotation so that ring gear (20) rotates one revolution in the opposite direction.





7. Observe pattern on the ring gear teeth and compare with "Differential Ring Gear Tooth Contact Pattern Diagnosis Chart."
8. If pattern is acceptable, remove J 39446.
9. Install rear axle housing cover.