Beginning late in the 1982 model year, the THM 200-4R transmission control valve assemblies were changed to eliminate the Torque Converter Clutch Valve Train (Figure #1). The computer command control unit (C-3) controls the converter clutch making the T.C.C. Valve Train unnecessary. The new control valve assembly (Figure #2) will have a solid bushing in it to direct oil flow.
When servicing any 1982 or 1983 THM 200-4R transmission that has a C-3 system (all except diesel and Canadian models), it is important that the proper spacer plate and gaskets be used. Refer to the following charts for proper usage.
1982 THM 200-4R
Transmission Control Valve Assembly, Spacer Model Plate & Gasket Service Package
BY 8634977 OG 8634978
1983 THM 200-4R
Transmission Control Valve Gasket Spacer Model Assembly Package Plate
BY 8639133 8634969 8639023 OG 8639218 8634969 8639026
SERVICE INFORMATION
The spacer plate and gaskets are included in the 1982 service packages to prevent mixing of the new and past design spacer plates. New gaskets (Figure #3) can be used with new and past design control valve assemblies. New spacer plates (Figure #4) cannot be used with past design control valve assemblies.
Location of the solid bushing is important. Locate the bushing so that the coiled pin fits into the groove of the bushing (Figure #2).
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.