Not a fullsize but it's a 94' s10 blazer 4.3 automatic with a 4L60E trans.

It takes off in 3rd (I think) and does not shift into overdrive. Had a shop look at it, said I needed new trans.

Replaced trans, torque converter and trans speed sensor. Well it's doing the same damn thing....any suggestions?

 

Was the replacement trans new or used?

Was the check engine light coming on before or after this issue?

It might be a computer issue. If you can find someone with OBD1 scan equipment to read live data it my point you in the right direction.

 

No codes, it was a rebuilt unit. It's going to a different transmission shop today, so I hopefully they can get it fixed. I am going to assume it's electrical.

 

I helped a buddy with an engine swap on a silverado a couple weeks ago. We had a similar issue. Somewhere during him rushing around he managed to pinch the wires going to the trans. Truck ran fine but had similar symptoms of what you described. Needless to say went back looking and found a wire cut. I hope its that simple for ya. Goodluck

 

I hope its that simple, I will let yall know of the outcome.

 

Does it have a factory converter, or an aftermarket high stall converter?

I ask because an aftermarket "loose" converter will make the computer think your transmission is slipping, and the PCM will default your trans to 3rd gear only. Custom tuning takes care of this, there are a couple DTC's that need to be deleted.

Hope this helps.

 

I removed the factory trans and TC. Replaced with rebuilt trans and reman. TC. Resetting the computer might help?

 

I would definately reset the computer.

 

It was the computer. Didn't need a new transmission afterall. Oh well lol

 

Bummer... I guess you wont be going back to the first shop since they misdiagnosed it.