LOW POWER/LACK OF PERFORMANCE INSTALL TRANS. TORQUE CONV.

Subject: LOW POWER/LACK OF PERFORMANCE

Model and Year: 1991-92 C2 & C3, K2 & K3, R/V TRUCKS

THIS BULLETIN CANCELS AND SUPERSEDES DEALER SERVICE BULLETIN NO. 92-175-6E, DATED APRIL 1992. THE LABOR OPERATION AND TIMES HAVE BEEN CHANGED. ALL COPIES OF 92-175-6E SHOULD BE DISCARDED.

CONDITION:

--------- Some owners of 1991-92 C/K and R/V trucks with the H.D. 5.7L engine (VIN K) and 4L80E (RPO MT1) transmission may comment of low power and/or lack of performance under normal operating conditions/temperatures. These low-power comments are mostly on heavy throttle maneuvers such as towing, highway passing, and on uphill grades.

CAUSE:

----- The transmission torque converter, engine and transmission calibration (MEMCAL) were not optimum in matching the engine torque curve.

CORRECTION:

---------- This service fix is for all 1991 and 1992 models built before the following VIN breakpoints:

Pontiac East: Chev= E159784 GMC = E523373 Oshawa: Chev =1173368 GMC = 1525884

To correct trucks:

1. Install transmission torque converter P/N 08685994.

2. Install Memcal per chart below:

New Memcal New Broadcast Code New Memcal I.D. Type Axle Prom Kit Memcal Label Scan Tool ---- ---- ---------- ------------------ --------------- C, R (2-Wheel All 16173069 BAAX 3001 Drive)

K, V (4-Wheel All 16173073 BAAY 3011 Drive)

3. Install TBI Body Kit P/N 17112900.

Part Availability:

Parts are currently available from GMSPO.

Warranty Information:

Labor Operation: Mem-Cal: T0500 Labor Time: 0.2 Hr.

Labor Operation: Torque Converter and TBI: T7516 Labor Times: "C" Models: 2.9 Hrs. "K" Models: 4.5 Hrs. "R" Models: 2.5 Hrs. "V" Models: 3.5 Hrs.

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.