SERVICE AND PARTS INFORMATION ON NEW PUMP ASSEMBLY VANE RINGS
New THM 700-R4 and 200-4R Transmission Oil Pump Assemblies with Nodular Iron Vane Rings. The new design vane rings will reduce the possibility of vane ring distress.
DATE OF PRODUCTION CHANGE: (Figure 1) -------------------------- Beginning April 28, 1987 (Julian date 118) all 1987 THM 700-R4 production transmissions and Service Replacement Transmission Assemblies (S.R.T.A.) were produced with these new vane rings.
Beginning June 17, 1987 (Julian date 168) all 1987 THM 200-4R transmissions were produced with these new vane rings.
The new design pump vane rings (212) can be used on any 1982 through 1987 THM 700-R4 transmissions and any 1981 through 1987 THM 200-4R transmissions. The past design vane rings can be used on any 1982 through 1987 THM 700-R4 transmission or any 1981 through 1987 THM 200-4R transmission, but it is recommended that the new iron pump vane rings be used when replacement of the vane rings becomes necessary.
THM 700-R4 transmissions only:
8657531 Pump Vane Ring (2 required)
THM 200-4R transmissions only:
8657692 Pump Vane Ring (2 required)
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.