4L60-E/4L65-E Automatic Transmission 2-3 Shift Clunk (Reprogram Powertrain Control Module (PCM) (05-07-30-012)

Publication date: 2005-05-09
Reference number: 05-07-30-012

4L60-E/4L65-E Automatic Transmission 2-3 Shift Clunk (Reprogram Powertrain Control Module (PCM)

TECHNICAL SERVICE BULLETIN

Reference Number(s): 05-07-30-012, Date of Issue: May 09, 2005

Affected Model(s):

2005 Cadillac Escalade; 2005 Chevrolet Avalanche, Silverado, Suburban, Tahoe; 2005 GMC Sierra, Yukon; with 4L60-E (RPO M30) or 4L65-E (RPO M32) Automatic Transmission

Condition

Some customers may comment on a 2-3 shift clunk noise. Typically, this clunk noise is most noticeable when the 2-3 shift occurs under approximately 48 km/h (30 mph).

Correction

IMPORTANT:

The PCM calibrations may REDUCE but not ELIMINATE the 2-3 shift clunk.
This bulletin only applies to the 2005 model year vehicles listed above.
As always, make sure your TECH 2(R) is updated with the latest software version.

To determine if this calibration will help to reduce 2-3 shift clunk, use the Tech 2 to navigate to the transmission diagnostic section and view the 2-3 shift adapt cells.
- If the 2-3 adapt cell values are negative, this calibration change will have minimal benefit in reducing the 2-3 shift clunk.
- If the 2-3 adapt cell values are above approximately + 5 psi, this calibration may provide a reduction in the 2-3 shift clunk.

IMPORTANT: These calibrations also contain the second gear start correction as detailed in bulletin 05-07-30-013 .

Technicians are to reprogram the PCM with an updated software calibration. This new service calibration was released with TIS satellite data update version 5 or later available May 1, 2005. Refer to Service Programming System (SPS) in Vehicle Control Systems in the appropriate SI Document.

Warranty Information

For vehicles repaired under warranty, use:

Warranty Information

Labor Operation	Description	Labor Time
J6355	Module, Powertrain Control - Transmission Reprogramming	Use Current Published Labor Time