A new final drive to transmission gasket (P/N 1627494) currently available through WDDGM has been released. When installing these gaskets, the listed service procedure must be used.
1. Apply a thin, even coat of anaerobic sealant (P/N 993010) or equivalent onto both sides of the gasket.
2. Clean both gasket mating surfaces on the transmission and the final drive, and inspect these surfaces for nicks, machining lines, or warpage. Also ensure that the bottom edge of the final drive housing does not interfere with the transmission pan.
3. Position the gasket onto the final drive unit, and install the final drive as outlined in the appropriate Service Information Manual.
General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.