Originally my Avalanche was doing fine, but then about halfway through my ten minute trip the truck stopped being able to shift from 1st to 2nd, and if it did, it then had trouble getting into 3rd. The next day I tried starting the truck, and the engine would turn on, all the electronics were fine, but then the engine would rev up, then drop to probably only 200-300 rpm, back up, until it finally died and left just the battery running. Any thoughts?
