REVISED TCC ENGAGEMENT SPEEDS (NEW PROM RELEASED)

VEHICLES AFFECTED: 1985 'F' Cars With LB9 5.0L TPI Engine (VIN Code F')

Customer comments of 'Chuggle' or 'Shudder' may be received on 1985 'F' cars with 5.0L TPI engines when the torque converter clutch engages at lower vehicle speeds.

This condition can be improved by the installation of a revised PROM which raises the TCC engagement speed to 65 KPH (41 MPH). Service PROM applications are listed below:

Application PROM P/N ----------- -------- Chevrolet With A/C 1227739 Chevrolet W/O A/C 1227740 Pontiac With A/C 1227741 Pontiac W/O A/C 1227742

NOTICE: These service PROMs will also raise vehicle idle speed to 650 RPM.

Use applicable labour time and operation numbers.

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.