| Subject: | No Reverse, Reverse Input Clutch Retaining Ring Out of Position |
| Models: | 2008 Chevrolet Avalanche, Colorado, Express, Silverado, Suburban, Tahoe |
| 2008 GMC Canyon, Savana, Sierra, Yukon, Yukon XL |
| Equipped with 4L60E or 4L70E (RPO M30 or M70) Automatic Transmission |
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
Condition/Concern:
Some customers may comment on a no reverse or slip in reverse condition. Disassembly of the transmission may find that the reverse input clutch retaining ring (614) has come out of the groove in the reverse input clutch housing (605).
Recommendation/Instructions:
Replace the reverse input clutch housing (605) and the reverse input clutch retaining ring (614), do not re-use these parts. Inspect the reverse input piston (607) and seal rings (608), reverse input backing plate (613), and input housing (621) for possible
damage and replace as necessary.
Note: Reference SI Document #1553208 for component numbers listed above.
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.
