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A/T Controls - Intermittent Highway Speed Chuggle

Bulletin No.: 06-07-30-020

Date: August 29, 2006

TECHNICAL

Subject:
LP1/LY7 Intermittent Engine Chuggle at Highway Speeds During Light Throttle Load (Reprogram Transmission Control Module (TCM))

Models:
2004-2005 Cadillac CTS, SRX, STS

with 2.8L or 3.6L V6 Engine (VINS T, 7 - RPOs LP1, LY7) and Automatic Transmission

Condition

Some customers may comment on an intermittent engine chuggle at highway speeds (typically above 100 km/h (62 mph)) during light throttle load.

Cause

This condition may be due to engine torque variation when the torque converter clutch (TCC) is at full lock.

Correction

A new transmission control module (TCM) calibration update has been released to correct this condition. This new calibration changes TCC full lock operation to a higher vehicle speed. Reprogram the TCM using SPS. This new calibration is available on TIS2WEB.

Warranty Information





For vehicles repaired under warranty, use the table.





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