Differential Runout Check

If the ring gear runout check (before disassembly) exceeds specification, the condition may be caused by a warped ring gear, a damaged case, excessively worn differential bearings or foreign material between mating surfaces (burrs, shavings, etc.). To determine the cause of excessive runout, proceed as follows:

1. Remove the differential case from the axle housing and remove the bolts that attach the ring gear to the differential case. Remove the ring gear from the case with a hammer and a drift.

Differential Assembly Installation:

2. Install the differential assembly including the bearing cups and shims in the axle housing. Tighten the bearing cap bolts to 109-128 Nm (80-95 ft-lbs).

Differential Assembly Rotation Inspection:

3. Rotate assembly to insure proper seating of differential bearings.

Differential Runout Check:

4. Check the runout of the differential case flange with a dial indicator TOOL-4201-C or equivalent. If the runout is within specification, (Max. 0.003 inch), install a new ring and pinion gear. If the runout exceeds specification, the ring gear is true and the trouble is due to either a damaged case or bearings. Visually inspect the bearings. If bearings are not damaged, replace both the case and bearings. Recheck the runout with new parts (case and bearings).

5. Install new differential bearings on the case hubs using Replacer Tool, D81T-4221-A or equivalent and install the differential assembly in the carrier without the ring gear.

NOTE: Press against the bearing cone only.

Differential Runout Check:

6. Check the case runout again with the new bearings. If the runout is now within limits, use the new bearings for assembly. If the runout is still excessive, the case is damaged and should be replaced.