Differential Assembly: Service and Repair
I-MARK & IMPULSE1. Working through access holes in axle shaft flange, remove four nuts and washers retaining the axle shaft dust shield and brake backing plate to the axle housing.
2. Remove rear axle shaft retaining plate.
3. Remove axle shaft with a suitable puller.
4. Remove differential cover and discard gasket.
5. Check and record ring gear backlash.
6. Mark differential side bearing caps and carrier with a punch so the caps can be reinstalled in original positions.
7. Remove differential side bearing cap bolts and caps.
8. Using two wooden hammer handles, pry differential case assembly from carrier. Do not drop or interchange differential side bearing outer races.
9. Insert adapter J-2241-11 in differential case bearing hub and remove side bearings using puller J-22888 with adapter leg J22939.
10. Remove the differential case to ring gear bolts and tap ring gear off case, using a mallet.
11. Remove the differential pinion shaft retaining pin, using a suitable 1/8 inch pin punch. Remove pinion shaft, pinion gears, differential side gears, and thrust washers.
Drive Pinion Removal & Disassembly
1. Remove torque tube assembly.
2. Using Special Tool J-22932, hold barrel spline and remove pinion preload nut.
Fig. 1 Barrel spline sleeve removal:
3. With Special Tool J-22937, remove barrel spline from drive pinion, Fig. 1.
4. Remove drive pinion by tapping rearward with a soft faced hammer.
Fig. 2 Rear pinion bearing removal:
5. Remove rear pinion bearing, using Special Tool J-22912, Fig. 2.
6. Remove pinion bearing outer races using a brass drift.
Drive Pinion Assembly & Installation
Fig. 6 Gauge shaft assembly installation:
1. Install front pinion bearing outer race using installer J-8611-01 and driver handle J-8092, Fig. 3.
Fig. 4 Rear pinion bearing outer race installation:
2. Install rear pinion bearing outer race, using installer J-7818 and driver handle J-8092, Fig. 4.
3. To determine the correct pinion depth setting, perform the following procedures.
4. Make certain all gauge parts are clean. Check particularly the discs, gauge pin ends, dial indicator tip and gauge plate surface.
5. Lubricate front and rear pinion bearings which will be used in final reassembly and position them in their respective races in the carrier.
Fig. 5 Pinion gauge plate installation:
6. Thread stud into gauge plate. With bearings held in place in races, install gauge plate and stud assembly on rear pinion bearing inner race, Fig. 5. Install pilot on front pinion bearing.
7. Install nut on stud. Hold stud stationary with wrench positioned on flats on end of stud; torque nut until a reading of 20 inch lbs. is obtained.
8. Make certain differential side bearing support bores are clean and free of burrs.
Fig. 6 Gauge shaft assembly installation:
9. Install discs on gauge shaft assembly, Fig. 6.
10. Position the gauge shaft assembly in the carrier so that the dial indicator rod is centered on the gauging area of the gauge block and the discs are seated fully in the side bearing bores. Install bearing caps and torque bolts to 45 ft. lbs.
11. Set dial indicator at ZERO. Then, position on mounting post of the gauge shaft with the contact button touching the indicator pad. Push dial indicator downward until the needle rotates approximately 3/4 turn clockwise. Tighten the dial indicator in this position and recheck.
12. Rotate gauge shaft slowly back and forth until the dial indicator reads the greatest deflection. At the point of greatest deflection, set the dial indicator to ZERO. Repeat rock action of gauge shaft to verify the ZERO setting.
13. After the ZERO setting is obtained, rotate gauge shaft until the dial indicator rod does not touch the gauge block.
14. Record dial reading at point position. EXAMPLE: If the dial reading showed .033 inch, this indicates a shim thickness of .033 inch.
15. Select correct pinion shim to be used during pinion reassembly on the following basis:
Fig. 7 Pinion marking:
a. Examine the head of the drive pinion. The pinion depth code is stamped by chemical ink, Fig. 7.
b. The number indicates a necessary change in the pinion mounting distance. A plus number indicates the need for a greater mounting distance (which can be achieved by decreasing the shim thickness). If examination reveals no pinion depth code, the pinion is ``nominal.'' If the figure is plus, convert the figure from hundredth millimeters to inches and subtract from step (11). If the figure is minus, convert the figure from hundredth millimeters to inches and add to step (11).
Fig. 8 Pinion shim chart.:
c. Use the chart, Fig. 8, to determine the proper shim variation to compensate for plus or minus markings.
Fig. 9 Rear pinion bearing installation:
16. Place shim on the drive pinion, then install the rear pinion bearing onto the pinion using installer J-21022, Fig. 9.
17. Lubricate pinion bearings and assemble the drive pinion, collapsible spacer, front pinion bearing, oil deflector plate and barrel spline sleeve in the differential carrier.
Fig. 10 Barrel spline sleeve installation:
18. Thread barrel spline sleeve installer J-22938 onto the drive pinion and draw the spline sleeve onto the pinion until there are sufficient threads of the pinion protruding to install the pinion preload nut, Fig. 10. Do not use installer J-22938 to adjust pinion preload. When the drive pinion endplay is eliminated, the preload specification is being approached. If this specification is exceeded, replace the collapsible spacer.
19. Remove installer J-22938 and install washer and pinion preload nut. Using Special Tool J-22932, hold barrel spline and tighten the preload nut until a preload of 6-13 inch lbs. (9 inch lbs. desired) with used bearings is required to rotate the drive pinion.
20. Install a new pinion oil seal that has been soaked in differential lubricant.