Testing Procedure
WARNING: This page is about a different car, the 2021 GMC Sierra 3500 HD and 2021 GMC Sierra 2500 HD. However, it is still accessible from the selected car via links, so may be relevant.
- Wipe clean the differential case, the ring gear and the differential carrier housing of lubricant. Carefully clean each tooth of the ring gear.
- Use a medium stiff brush in order to sparingly apply gear marking compound GM P/N 1052351 (Canadian P/N 10953497) or equivalent to all of the ring gear teeth.IMPORTANT:
Avoid turning the ring gear excessively.
- Using a wrench, turn the drive pinion flange/yoke so that the ring gear rotates at least 3 full revolutions.
- Turn the drive pinion flange/yoke in the opposite direction so that the ring gear rotates at least 3 full revolutions in the opposite direction.
- Observe the pattern on the ring gear teeth. Compare the pattern with the following illustrations.
- Once the proper pattern is obtained, continue the assembly of differential carrier. Front Axle Assemble