PUMP BODY ASSEMBLY/THM200-C NEW DESIGN SERVICE REPLACEMENT

MODELS: 1982-1983 S-TRUCK WITH THM 200

Beginning in early March, 1983, a new design pump body assembly went into production for all 1982 and 1983 THM 200-C transmissions used in S-truck applications. The new design pump body assembly has the pressure relief port removed from the body casting (Figures No. 1 & 2).

When servicing any 1982 or 1983 THM 200-C transmission used in the S-truck, that necessitates that the pump body assembly be replaced, order service parts as listed as follows:

Model Pump Body Pump Cover

C7, CN, CO, CK, CB, CW, HB, HF, HH, HL, 8638922 8633958 PS, C9, CS, HO, & JJ

The old style pump body assembly should not be used in the S-truck application.

The new design pump body casting will have part number 8648111 cast into it. Verify that you have the correct part before installing in into the vehicle.

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.