According to a technical service bulletin issued in 2012 (PIP3136P), General Motors was aware of a number of issues that could cause the serious and expensive transmission problems in the 2003 – 2012 Chevy Tahoe. So let’s investigate and find out what the problems could be.
What Transmission Do I Have?
Reasons your 2003 – 2012 Chevy Tahoe 4L60 could be slipping
If you discover that your transmission is slipping when going into 2nd, 3rd or 4th gear, subsequent diagnosis could be a failed 2-4 band and/or 3-4 clutch. If the transmission fluid is at the proper level and is fresh and clean, and the root cause may be one of the following items:
Low line pressure
Cracked or broken 1-2 accumulator piston
Damaged 2-4 servo piston seals
Scored 2-4 servo apply pin
Scored 2-4 servo piston bore
Servo feed oil passage blocked with sediment
Damaged for word clutch apply piston seals
Cracked forward clutch apply piston
Damaged turbine shaft oil seal rings
Turbine shaft check valve retainer and ball assembly (if the check ball is missing, it’s gone inside of the torque converter, and the torque converter will have to be replaced)
Damaged 3-4 clutch apply piston seals
Cracked 3-4 clutch apply piston
Blocked 3-4 clutch and forward clutch oil feed passages
Damaged overrun clutch seal
Leaking or unseated 3-4 clutch check ball and/or #7 check ball
Undersized 4-3 sequence valve
Stuck boost valve
Damaged input sun gear to input carrier thrust bearing
Cracked or damaged oil pump body
Damaged forward sprag
Worn or damaged rear stator shaft bushing
Out-of-spec transmission pump cover
Should none of these issues present themselves, then the input housing, forward and clutch piston and 3-4 clutch piston should be replaced. Hilariously, the TSB says that the transmission should simply be replaced if the problem presents itself again.
What Transmission Do I Have?
Or you could save yourself a lot of time and money in the first place, and replace it with a remanufactured 4L60E transmission from Street Smart Transmission. All of the problems listed above have already been corrected by R&D department before the transmission is put into production. And it comes with a three year/unlimited mile warranty that is good at any licensed repair shop in the country. Some of you want to keep your truck on the road for as long as possible, this is the best way to go about it. To learn more, click here.
