2008 Chevrolet Uplander please help

Has the check engine light come on? Have you checked trans fluid to make sure it is clean and tight? Also, what work was just done to it?

I had a speed sensor front wheel hub assembly the throttle body cleaned and I took it to a tran man and he said he put it on the coumputer and it didn't put any codes out the shop that done the work said they had it on a computer and they couldn't find nothing I am stumped

That is what happens today. With all our technology, if there isn't a code, the mechanic is lost. I hate to admit, it becomes a guessing game without the computer, but that is what being a mechanic was all about years ago. Diagnose the problem without a computer.

I have to be honest, it sounds like the transmission is slipping for you. That problem will not show a trouble code. Did the trans tech drive the vehicle?

Ya he said its wasn't the tranny he said the tac was doin it but I had other people say that it wouldn't cause it

TCA? Do you mean TCM?

No the tachometer is what he says

I hate to say it, but I'm not sure how the tach would cause a transmission problem.

You got me but thanks alot

Wish I could have helped more. Let me know if you have have other questions.