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TWO PIECE PARK/LOCK ROD CHANGE NEW ONE PIECE DESIGN-THM200-4R

MODELS AFFECTED: ALL 1983 THM 200-4R TRANSMISSIONS

Beginning in October, 1982, the parking lock rod assembly, in all 1983 THM 200-4R transmissions, was changed to a one piece assembly (Figure #1). Previously, the parking lock rod assembly was a two piece assembly (Figure #2).

In servicing any THM 200-4R with this parking lock rod assembly, it is important that the correct detent lever be used. Refer to the chart below for proper usage of the parts for the parking lock rod assembly. These parts are not interchangeable.

First Design (Two Piece)

Rod Assembly - Parking Lock 8639110 Lever - Inside Detent 8634184

Second Design (One Piece)

Rod & Lever Assembly - Parking Lock 8634991


Object Number: 89047  Size: MF

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.