SHIFT BUSYNESS IN CRUISE THM 200-4R TRANSMISSION

MODELS AFFECTED: 1981 DEVILLE AND BROUGHAM SERIES VEHICLES

This bulletin updates Serviceman Bulletin 83-107. Changes to the original bulletin are shaded for reference. This change affects the THM 200-4R transmission only. Bulletin 83-107 should be retained for information concerning the THM 325-4L transmission.

Some 1981 rear wheel drive Cadillacs equipped with 4.1L V-6 engines may experience a transmission shift busyness at highway speeds with the Cruise Control engaged. Shift busyness refers to cycling of the transmission between fourth and third gears. This condition is most noticeable while driving up inclines.

To correct this condition, install service package 8634995 into the control valve assembly. This package contains:

1 - 3-4 Throttle Valve 1 - 3-4 Throttle Valve Bushing 1 - 3-4 Throttle Valve Spring 3 - Coiled Steel Pins 1 - TV Spring 1 - TV Mod. Upshift Spring 1 - Instruction Sheet

Refer to 1984 Service Information Manual, Section 7A, for on-car R&I procedures as well as Section 200-4R for proper disassembly and reassembly of the control valve assembly, and the instruction sheet contained in the service package for installation of the above parts.

For warranty purposes, use labor Operation No. K6560 at 1.2 hours.

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.