GEAR WHINE NOISE IN FIRST GEAR REPAIR PROCEDURE -P/N

MODELS AFFECTED: 1982-1987 RWD DE VILLES AND BROUGHAMS

Some Cadillacs equipped with a THM 200-4R transmission may experience a gear whine in first gear, which may also be evident in second gear. This condition may be the result of excessive forward clutch shaft and output shaft end play causing a wear pattern on the front planetary gears. To repair this condition, replace the front internal gear, front carrier assembly, and front sun gear. The appropriate part numbers are listed below:

Front Internal Gear: P/N 8639947

Front Carrier Assembly: P/N 8628174

Front Sun Gear: P/N 8628190

Revised end play specifications have been developed for the forward clutch shaft and the output shaft to prevent recurrence of gear whine. Refer to the following end play specifications when replacing noisy front planetary gears: Forward Clutch Shaft .9 - 1.3mm (.036" - .051") Output Shaft .32 - .65mm (.012" - .026")

Refer to the appropriate Service Information Manual 200-4R section for proper overhaul and end play checking procedures.

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.