Subject: | Flare, Late Or Delayed Shifts, Metal Debris in Transmission Pan |
Models: | 2006-2008 Buick Allure, Lacrosse, Lucerne, Rendezvous, Terraza |
| 2006-2008 Chevrolet Impala, Uplander |
| 2006-2007 Chevrolet Monte Carlo |
| 2006-2008 Pontiac G6, Grand Prix, Montana SV6 |
| Equipped With a 4T65E Transmission RPO Codes M15, M76, MN7 |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Customer may comment that the vehicle exhibits a shift flare, late or delayed shifts. Technicians may find various shift performance codes and metal debris in the transmission pan. The concern may be caused by sticking valves in the valve body due to delamination
of the either the drive or driven sprocket bearing surface.
Recommendation/Instructions:
Closely inspect the drive and driven sprocket bearing surfaces for delamination (See photo). If delamination is found replace the sprocket and corresponding bearing. Make sure to thoroughly disassemble clean and reassemble the valve body prior to reassembling
the transmission to ensure there are no sticking valves.
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.