Transmission slips GM truck
GM has issued a service bulletin to address a Transmission slips GM truck, transmission flares issue on several GM trucks. If you own a 2012 Chevy Avalanche, Silverado, Suburban, Tahoe, or GMC Sierra, Yukon with the 5.3L engine and 6L80 automatic Transmission, then read this post.
The Transmission slips GM truck issue appears as a 2-3 shift flare when cold, especially after sitting for a while. The problem is most prevalent in colder climates and it caused by a software issue in the transmission control module (TCM). DON’T replace any parts.
Reprogram the TCM with the latest software update. Get your vehicle reprogrammed at any GM dealer or independent shop that’s has reprogramming capabilities. The charge should be less than $150