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

 

Is your check engine light on? If it is, scan it and post the codes

 

Something I always recommend is running a good Cleaner through it before any major repair is started. It may not be effective, but if it is, it's a cheep way to resolve issues. Then of course an eventual Fluid and Filter change if the problems are resolved.

 

Help! Please! Replaced tranny 8 years ago and then the truck sat for the last 8 years with only 2000k miles on new tranny. Changed all fluids except tranny, still had good color! Checked fuses, wiring, basic replacements. Drove for a month and all of a sudden on my way home from work, truck wouldn't go into overdrive! Shifts fine and smooth from 1-3 but 3rd is running at high rpms. Also emergency brake lights and brake alarms came on, messed with wiring under the dash and lights finally went off but tranny still acting up. In 3rd if I let off the gas it feels as if I'm coasting in neutral. Any suggestions on where to start? Thank you in advance!!