A/T - Low Power, Lack of Performance With 4L80E

Number: 92-175A-6E (REVISED)

Section: 6E

Date: JUNE 1992

Corporate Bulletin No.: 236507R

ASE No.: A1, A8



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 MTI) 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.






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.