I have a 1991 Lumina APV van. It’s the 3.1L 3 speed. I have the cradle down and the engine and transmission off of it to replace the engine.

Seems it’s all down anyway I would like to swap it for a 4 speed auto. I know I have some potions. I could go older with the TH440 or I can go around this van’s vintage with the 4T60 before they were electric.

Here’s where I’m asking for advice: out of what car should I grab the transmission and what about the CV axles. If I need to get the transmission out of one type of car and the axles out of another, that’s fine.

I see that my transmission that’s currently in it is compatible with Buick Centurys. Am I correct in thinking that if my transmission and my CV joints will fit in a Century, then will the Century 4 speed and its CVs fit in my van?

I believe if I go a little bit older there isn’t the worry about the electrical connection but then again, I’m not afraid to look at wiring diagrams to make a torque converter lock-out work.

I believe that whatever transmission I go with I’ll have to run a vacuum line but that’s no big deal.

Can anybody tell me if there is a 4 speed that will bolt up and work with CV shafts being changed? If there is going to be modification required can anybody lend me some advice on what transmission would be best to go with?

I’ve done hours of research across multiple forums and all I can find is some Fierro guys who’ve done this with their cars and I’m unsure how well that translates over to this van.

I appreciate any insight and advice. Thanks for taking the time to read this.