For 1990-2009 cars only
4L60-E/4L65-E Automatic Transmission 2-3 Shift Clunk (Reprogram Powertrain Control Module (PCM))
| Subject: | 4L60-E/4L65-E Automatic Transmission 2-3 Shift Clunk (Reprogram Powertrain Control Module (PCM) |
| Models: | 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® 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.
- 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.
| • | 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.
Warranty Information
For vehicles repaired under warranty, use:
Labor Operation | Description | Labor Time |
|---|---|---|
J6355 | Module, Powertrain Control - Transmission Reprogramming | Use Current Published Labor Time |
