Some 1982 and 1983 Rivieras with BE model 325-4L transmissions may experience a shift "busyness" which is most noticeable while driving up inclines and in cruise control. "Busyness" refers to cycling between fourth and third gear.
Beginning on April 22, 1983, with transmission serial number 3931, a revised control valve assembly went into production for all 1983 THM 325-4L BE model transmissions to correct this condition.
When servicing any 1982 or 1983 THM 325-4L BE model transmission produced before the above serial number for this "busyness" condition, order service package number 8635944. This package contains:
(1) 3-4 Throttle Valve (1) Bushing, 3-4 Throttle Valve (1) Spring, 3-4 Throttle Valve (1) Clip, Valve Retaining (1) Pin, Coiled Spring (1) Instruction Sheet
Refer to the instruction sheet contained in the service package as well as the service manual for proper disassembly and reassembly of the control valve assembly.
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.