Runout
DESCRIPTIONIf the ring gear runout check (before disassembly) exceeds specification, the condition may be caused by a warped ring gear, a damaged rear axle housing loss of differential bearing preload or debris between the ring gear back face and the case flange. To determine the cause of excessive runout, proceed an follows:
PROCEDURE
1. With the pinion removed, place differential case/ring gear subassembly with differential bearings and differential bearing cups in rear axle housing.
2. Install a 6.75 mm (0.265-inch) differential bearing shim on the LH side of subassembly.
3. Install the LH bearing cap finger-tight.
4. Install progressively larger differential bearing shims on the RH side until the largest differential bearing shim selected can be assembled with a slight drag feel.
5. Install the RH side bearing cap. Install bearing cap bolts. Tighten to 95-115 Nm (70-85 ft. lbs.).
6. Rotate the assembly to make sure differential rotates freely.
7. Install Dial Indicator with Bracketry TOOL-4201-C or equivalent. Check and note ring gear runout.
8. If the runout is within specification, the original out-of-specification runout was caused by insufficient differential bearing preload. If the runout exceeds specification, proceed to Step 9.
9. Remove differential case from the rear axle housing.
10. Remove ring gear using a drift that will bottom in ring gear bolt holes. Strike at alternate holes around gear.
11. Install differential case in carrier without ring gear.
12. Check runout of differential case flange with Dial Indicator with Bracketry TOOL-4201-C or equivalent.
- If runout is within specification (maximum 0.076 mm, 0.003 inch), install a new differential ring gear and pinion.
NOTE: Ring gear and pinion are matched and MUST be replaced as a set.
- If runout exceeds specification, ring gear is true and concern is due to either a damaged differential case or differential bearings. Inspect differential bearings. If differential bearings are not damaged, replace both differential case and differential bearings. Recheck runout with new parts (differential case and differential bearings).
13. Press new differential bearings on differential case hubs using Differential Side Bearing Replacer T57L-4221-A2. Install differential assembly in carrier without differential ring gear and pinion.
NOTE: Press against the differential bearing only.
14. Check case runout again with new differential bearings.
- If runout is within limits, use new differential bearings for assembly.
- If runout is still excessive, differential case is damaged and should be replaced.