2003 Silverado LS auto transmission 1st gear problems
Bought this vehicle back in '04 and it has always had a hard 'thunk' when shifting from 1st to 2nd and I thought, well, maybe it just shifts hard, but this weekend a new condition has occurred. Now it sticks in 1st gear and will stay there at very high rpms, unless I back off the accellerator and then pump the gas to coax it into shifting to 2nd. There are no problems once in 2nd, although the oil pressure gauge is pegged at max all the time. I've driven it about 8 hours since this first started.
Any suggestions or similar stories are appreciated. I'll bring it in if I need to, but if it is something like a pump or filter or anything else I may be able to save a few hundred dollars on by doing it myself, I'm game.