C 1500 Yukon 2WD V8-4.8L VIN V (2000)
PROM - Programmable Read Only Memory: Customer Interest
A/T - Wide Open Throttle 1-2 Double Bump/Harsh Shift
File In Section 06 - Engine/Propulsion System
Bulletin No.: 99-06-04-049
Date: October, 1999
TECHNICAL
Subject:
Wide Open Throttle (WOT) 1-2 Double Bump and/or Harsh Upshift (Reprogram PCM)
Models:
2000 Chevrolet and GMC C/K Models (Silverado and Sierra) With 4.8 L Engine (VIN V - RPO LR4) and 4L60-E Automatic Transmission (RPO M30)
Built Prior to the following VIN Breakpoints:
Plant
VIN Breakpoint
Pontiac East
YE124221
Fort Wayne
YZ124556
Oshawa
Y1108340
Condition
Some customers may comment on a double bump or harsh shift when making a wide open throttle (WOT) 1-2 upshift.
Cause
Some early built 2000 model year production Siverado and Sierra pickups, with the 4.8 L engine and the 4L60-E automatic transmission, were built with
an engine calibration that may place the engine fuel cut-off RPM too close to the transmission 1-2 WOT upshift point.
Correction
A new calibration has been released, raising the engine fuel cut-off to 6000 RPM. Reprogram the PCM with the new calibration listed below.
Parts Information
Previous
New
Calibration
Calibration
Description
16263681
9357621
C/K 10 003-53
and LR4 and M30
The calibration listed is an electronic calibration and is NOT available from GMSPO. The calibration will be available from Techline starting August
12,1999, on the TIS 2000 Disc 17 CD ROM.
Warranty Information
For vehicles repaired under warranty, use:
Labor
Operation
Description
Labor Time
J6355
Prom-Reprogramming
Use published
On Vehicle
labor operation
time