I have a Chevy Avalanche I bought off a friend it is a 2002 and has only been serviced by the dealer its whole life. He said under 2 years ago the tranny went and they replaced it or rebuilt it (hes looking for the paper work). I have only been using it as a second vehical with little driving. One day pulling away from a red light it starts to revv high and go nowhere... like its slipping, turns out first gear is good, second gear works just fine, 3rd gear and Drive are the problem, it just seems to rev to about 3,000 rpm then rev to the moon and go nowhere. do i have to replace the whole transmission could it be a smaller part like a solenoid or something? thanks

 

most often if its completing the shift and slipping in that gear it will need a tear down.