Drive Pinion Yoke Replacement

Removal Procedure
^ Tools Required
- J 8614-01 Companion Flange Holder

Important: Observe and mark the positions of all the driveline components, relative to the propeller shaft and the axles, prior to disassembly. These components include the propeller shafts, drive axles, pinion flanges, output shafts, etc. Reassemble all the components in the exact places in which you removed the parts. Follow any specifications, torque values, and any measurements made prior to disassembly.

1. Raise the vehicle. Refer to Vehicle Lifting.
2. Remove the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Steering and Suspension.
3. Remove the brake drums.
4. Remove the propeller shaft. Refer to Propeller Shaft Replacement - Rear.





5. Measure the amount of torque required to rotate the pinion. Use an inch-pound torque wrench. Record this measurement for reassembly. This will give the combined preload for the following components:
^ The pinion bearings
^ The pinion seal
^ The carrier bearings
^ The axle bearings
^ The axle seals
6. Draw two arrows pointing at each other. One on the pinion stem. The other on the pinion yoke/flange.
7. Record the number of exposed threads on the pinion stem for reference.





8. Remove the pinion yoke/flange nut and washer. Hold the pinion yoke/flange using the J 8614-01.





9. Remove the pinion yoke/flange using the J 8614-O1. Use a container in order to retrieve the lubricant.


Installation Procedure
^ Tools Required
- J 8614-O1 Companion Flange Holder
1. Apply sealant (GM P/N 12346004 or equivalent) to the inside sealing surface of the pinion yoke/flange.
2. Apply seal lubricant (GM P/N 12377985 or equivalent) to the outside sealing surface of the pinion yoke/flange and the sealing lip of the pinion seal.

Notice: Do not hammer the pinion flange/yoke onto the pinion shaft. Pinion components may be damaged if the pinion flange/yoke is hammered onto the pinion shaft.

Important: Install the pinion yoke/flange in the same position as marked during removal to maintain driveline balance.

3. Install the pinion yoke/flange by tapping it with a soft-faced hammer until a few pinion shaft threads show through the yoke/flange.





Notice: Refer to Fastener Notice in Service Precautions.

Important: Reference the number of exposed threads on the pinion shaft recorded during removal.

4. Install the washer and a new nut using the J 8614-01.
^ Tighten the nut until the pinion end play is just taken up. Rotate the pinion while tightening the nut to seat the bearings.





Important: If the rotating torque is exceeded, the pinion will have to be removed and a new collapsible spacer installed.

5. Measure the torque required to rotate the pinion, using an inch-pound torque wrench. Compare this value with the rotating torque recorded during removal.
^ Tighten the nut in small increments, as needed, until the rotating torque is 0.40 - 0.57 Nm (3 - 5 inch lbs.) greater than the rotating torque recorded during removal.
6. Once the specified torque is obtained, rotate the pinion several times to ensure the bearings have seated. Recheck the rotating torque and adjust if necessary.
7. Install the propeller shaft. Refer to Propeller Shaft Replacement - Rear.
8. Inspect and add axle lubricant to the axle housing, as necessary. Use the proper fluid. Refer to Lubrication Specifications and Fluid and Lubricant Recommendations.
9. Install the brake drums.
10. Install the tire and wheel assemblies. Refer to Tire and Wheel Removal and Installation in Steering and Suspension.
11. Lower the vehicle.