2_wacko

iTrader: (2)

I have a 99 GMC 4.8, and had the trans filter and oil changed. When I drove the truck it felt like it was in a high gear only. No power, takes off real slow then gains speed, but never shifts. Also got the SES light on when it never has came on what could be the problem thanks?

2004SSS

iTrader: (25)

seeems like you could have pinched or hit a connector to a solenoid in the pan not allowing 1st gear. id pull the pan and check all your connections, i recently serviced my trans and had to take it back apart and reconnect one, i didnt have 4th or lock up and it was a bitch to do .

my black ss

iTrader: (7)

Yes probably pinched a wire or knocked a conector loose .... Or maybe if the guys who changed it disconected something with the key on it would send a code and posably confuse the pcm...Reboot the system before you pull the pan off ... Im not sure if these trucks will do that. But my dads 6.5 deisel (94) has a bad conector in the pan and somtimes when it acts up it will not let first work rebooting it takes care of it

2_wacko

iTrader: (2)

Thanks one of the connections was loose.

Torque_Wrench

iTrader: (13)

These guys are right dude! You've probably pinched a wire gojng to a shift solenoid. Because your truck is pulling out in drive and not 1st or 2nd. Go have your truck scanned and tell us the code and we can help you more.