Sierra 1500 4WD V8-6.0L VIN U (2006)
12. Remove the pinion oil seal. Use a suitable seal removal tool. Do not damage the housing.
Installation Procedure
1. Install a new pinion oil seal using the J 22388.
2. Apply sealant GM P/N 12346004 (Canadian P/N 10953480) or equivalent to the splines of the pinion yoke.
3. Install the pinion yoke. Align the marks made during removal.
4. Seat the pinion yoke onto the pinion shaft by tapping it with a soft-faced hammer until a few pinion shaft threads show through the yoke.