2005 Tahoe Brakes/Tranny Mystery

I have a 2005 Tahoe 2wd w/Autoride system. Only 7K miles of city driving in Texas and no towing. The problem is after a moderate to hard stop there is a lunge on acceleration and an occasional rough shift from 1st to 2nd. Almost feels like a clutch slipping in the tranny or loose u-joints. The car was serviced @ 3200 miles and the tranny is full.

Although the car is still under warranty I'm wondering if anyone else has had this problem and what the cause may be before I take it to the dealer. Thanks for any suggestions