GM Service Manual Online
For 1990-2009 cars only

REAR AXLE NOISE NEW PROPSHAFT INTERNAL DAMPER

SOME EARLY BUILT 1982 'F' SERIES VEHICLES EQUIPPED WITH AUTOMATIC TRANSMISSIONS MAY EXHIBIT REAR AXLE NOISE WHICH MAY BE OBJECTIONABLE TO SOME CUSTOMERS. TO CORRECT THIS CONDITION, A NEW PROPSHAFT WITH AN INTERNAL DAMPER HAS BEEN RELEASED FOR PRODUCTION AND IS NOW AVAILABLE FOR SERVICE. THE NEW PROPSHAFT (PART NUMBER 7840541) WILL HAVE, PAINTED RADIALLY AROUND THE TUBE, ONE (1) WHITE AND ONE (1) BLUE STRIPE. THE INTERNAL DAMPER IS LOCATED AT THE SLIP YOKE END AND EXTENDS APPROXIMATELY 240MM. TAPPING ON THE PROPSHAFT TUBE SECTION AT THE MID-SECTION AND AGAIN AT THE SLIP YOKE END WILL PRODUCE A DEADENED RING AT THE SLIP YOKE END. IF A VEHICLE BUILT PRIOR TO THE FOLLOWING BUILD DATED EXHIBITS REAR AXLE NOISE ONLY WHICH IS NOT NOISE DUE TO AN INTERNAL AXLE MALFUNCTION , THE DAMPENED PROPSHAFT SHOULD BE INSTALLED. L - VAN NUYS JANUARY 14, 1982 N - NORWOOD JANUARY 18, 1982

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.