You are not going to like to hear this but this is normal and yes you have an adaptive transmission computer that is constantly adjusting to the way its being driven. You can take it back to the dealer all you want but nothing it going to change as the dealers have no fixes. Its the way the new computerized vehicles operate. It will get better as the miles roll up, give it 20,000-30,000 miles and you will adapt, I did.
Mike
2015 Sierra Denali 6.2L 8L90 Crew Cab Standard Box 4WD
