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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 1999 🢒 GMC C-Series Medium Duty Truck B7 🢒 Bulletins 🢒 Poor Engine Performance and/or Transmission Shift Quality (Reflash Calibration)

Poor Engine Performance and/or Transmission Shift Quality (Reflash Calibration)

Subject:Poor Engine Performance and/or Transmission Shift Quality (Reflash Engine Calibration)

Models:1999-2000 Chevrolet and GMC B, C, and F Medium Duty Models
With Caterpillar® 3126 Engine (VIN C -- RPO LG5) and Allison® Transmission (Model AT545)


Condition

Some drivers may comment on poor engine performance and/or poor transmission shift quality.

Cause

This condition may be related to engine horsepower.

Correction

Verify that the engine horsepower option is 190 hp (RPO LSW). Contact the nearest GM authorized Caterpillar® dealer equipped with a CAT ET and reflash the Powertrain Control Module (PCM) with the most current 190 hp high performance (AT545) calibration. See service information for instructions.

Warranty Information

For vehicles repaired under warranty, use:

Labor Operation

Description

Labor Time

J6355

Powertrain Controller - Reprogram

0.5 hr