DRIVELINE STOP CLUNK SPECIAL LUBRICANT

VEHICLES AFFECTED: 1988-89 C1,C2 WITH 700R4/4L60 AND 400/3L80 AUTOMATIC TRANSMISSION

Normal driveline tension build-up is released in vehicle braking on some 1988-89 C1 and C2 models (with single piece propshafts and automatic transmissions) as driveline clunk when stopping. The tension build-up is the result of the driveshaft splines binding on the transmission slip yoke.

To eliminate stop clunk due to spline-yoke bind, the driveshaft splines should be lubricated with a special lubricant.

NOTICE: This procedure should be applied to 1988 and 1989 C1, C2 vehicles with automatic transmissions and one-piece, propshafts only. When applied to other vehicles, possible transmission lube contamination could result.

PARTS: 500 ml can of special lubricant, GM P/N 12345718, should service about 50 vehicles.

SERVICE PROCEDURE

1. Remove driveshaft.

2. Clean slip yoke and inside of driveshaft spline with solvent and clean cloth.

3. Apply grease to slip yoke spline with a brush or swab, so as to completely cover the entire spline with a light coating of grease.

4. Reinstall propshaft.

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.