Ok, I have searched and searched this forum, and I am unable to find a definite answer on this. I have the 4T60-E, will the 4T65-E work in my car?

Definate answer

No it will not work unless you change wiring harnesses and pcms and more than it'* worth.

Thank you very much. I now know what NOT to get when I goto the yard.

Better yet... you may need the exact year.. hang in til some of the experts give you the low down.

They changed connectors and things over the years.. it'* pretty crazy and you are probably limited to 94/95 for replacements.

That was going to be my next question tommorow(by the time I realized it)

So, what years am I limited to?

1995 is for sure, 1994 MIGHT work for you. If you get a 95 FROM A BONNEVILLE, you'll be fine. Buick LeSabre'* and other similar cars had different gear ratios. Make sure you are 3.06 before you go, and make sure the donor car had a 3.06.

I have the 3.06
On the subject of 3.06, what if its NOT a 3.06? Won't work?

EDIT
Is it possible to look on the transmission to determine what exactly it is? Or, do I have to go by the RPO list?

I think the trans has a tag somewhere on them that correctly ID'* them.

YOu want to ensure a 3.06 because otherwise your trans will not shift properly and at the right times.

Oh, so its back to the PCM issue again huh? Current PCM thinks the tranny is a 3.06, but its not and it shifts differently correct?

You got it...

Round hole...square peg theory..

With a big enough hammer...it might fit...but it'll never be right.