K 1500 Truck 4WD V8-5.7L VIN R (1997)
Engine Control Module: Customer Interest
A/T - Chuggle/Surge on TCC Apply/No DTC's
File In Section: 7 - Transmission
Bulletin No.: 77-71-53
Date: April, 1997
Subject:
Chuggle/Surge on TCC Apply/No DTC's (Reflash PCM)
Models:
1996-97 Chevrolet and GMC C/K, G Models
with 5.7L Engine (VIN R - RPO L31) and HYDRA-MATIC 4L60-E Transmission (RPO M30)
Condition
Some owners of the above models may experience a chuggle/surge when TCC is applied under light throttle acceleration.
Cause
Engine inputs (Combustion events) exciting the vehicle platform/driveline or tire balance may be a contributing factor.
Correction
First ensure the most recent engine, not transmission calibration has been installed (Corp. # 76-65-04) and check tire balance.
A new transmission calibration to correct chuggle/surge is available for use on vehicles with persistent concerns only.
Important:
This calibration will raise TCC engagement approximately 7-10 mph depending on application. This calibration should not be installed until the
engine calibration listed above has been installed. Installation of this calibration may lead to decreased fuel economy due to TCC engagement at
higher speeds.
Reflash the Powertrain Control Module with the appropriate part numbers below.
Refer to your Service Manual for proper procedure.
Parts Information
This new calibration will be available starting with the 1997 Disc 4 update.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation
Labor Time
J6355
Reflash Control Module
Use published labor operation time.
