EARLY TRANS CONVERTER CLUTCH APPLY (INSTALL NEW PROM)

TRANSMISSION APPLICATIONS: 4.3L AND 4L60 AUTOMATIC TRANS.

SUBJECT: EARLY TRANSMISSION CONVERTER CLUTCH APPLY (INSTALL NEW PROM)

VEHICLE APPLICATIONS: 1992 S/T TRUCK WITH 4.3L AND 4L60 AUTOMATIC TRANSMISSION

Condition:

---------- Some owners of 1992 S/T trucks with 4.3L (LB4) engines and automatic transmissions may comment on early transmission converter clutch (TCC) engagement, TCC engagement just after the 2-3 upshift, or lack of power.

Cause:

------ The torque converter clutch is applied at low speeds during some driving conditions.

Correction:

----------- To correct this condition install a new calibration PROM which raises the TCC apply speed. This calibration will increase the TCC apply speed on a 1992 vehicle to be similar to a 1991 vehicle. (See below)

Part PROM Scanner Number Application Broadcast I.D. ------- ------------ ------------ ---------- 16175285 Federal BARL 5551

For vehicles being repaired under warranty use:

Labour Time: 0.8 Hour

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.