NEW PUMP ASSEMBLIES P/N FOR SLIDE SPRINGS

1985 THM 700-R4 YA, YC, YZ MODELS

Beginning on March 4, 1985, or Julian Date 064, (refer to Figure 1) a new pump assembly went into production for 1985 THM 700-R4 "YA", "YC" and "YZ" model transmissions.

This new pump assembly uses an inner slide spring and an outer slide spring (refer to items 243 and 209 of Figure 2) or nested slide springs, that lowers the wide open throttle 3-4 upshift.

To update pump assemblies used in 1985 THM 700-R4 "YA", "YC" or "YZ" model transmissions built prior to Julian Date 064, the following springs may be ordered from W.D.D.G.M.:

8639562 - Inner Pump Slide Spring 8639563 - Outer Pump Slide Spring

Use procedures contained in the appropriate Service Information Manual and the illustration provided in 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.