GMC TSB #PIP5012D
2012 GMC Sierra
Affected Component: ELECTRICAL SYSTEM
- Summary
- This Preliminary Information communication provides information to the technician about vehicles that have a clunk noise or a harsh 6-5 downshift while driving at 50 to 70 miles per hour. Technician will reprogrammed the Transmission Control Module and a FastLearn procedure will need to be performed to correct the condition.