I'm swapping from a th400 to a th350, and I need to know if i need a stock driveshaft. I've heard they'll fit with the 350, and where is a good place to get one? Not one of the junk yards around here have one.

 

You have a TH400 and are going to put in a TH350?

There are 2 different lengths depending on the tranny. A long tail shaft TH350 (9") can use a driveshaft from a third gen that has a 700R4 tranny. A short tail shaft TH350 (6") needs a driveshaft from a 82-83 third gen that came with the 3 speed auto (A 200c tranny)

 

Thanks thats what I neede to know. The peopl at summit and jegs had no idea.

 

you're making an issue out of something that shouldn't be. you can get a DS in any length you want out of just about any tube you want.

 

Sure, if you're like me and have one custom made. I had 2 made now. First one was 3" x .083" walled steel tube with 1350 ends. It was expensive because I had buy everything new. I've changed transmissions and moved my engine/tranny back since then. This winter after installing my 4-link, I measured out the driveshaft length required. I needed one 1-5/8" longer for a perfect fit. They cut off the 1350 ends, welded in a longer tube then rebalanced the driveshaft. Much cheaper than the first one since I didn't need to buy new ends.

If you're just doing a simple tranny swap, there's only a couple of choices when reusing a factory driveshaft.

As for finding a junkyard driveshaft, only f-body driveshafts will fit in f-bodies. Other cars like G-body etc are too long. F-bodies have a very short wheel base.