I went to a local guys house to buy a driveshaft for my 71 340 cuda 833 tranny 8 3/4 rear. He shows me a drive shaft that he has for sale . It was the correct length but it had a small rear u-joint. My question is ,,, Did a 340 71 cuda with a 833 tranny come with a small rear u joint or should it have the bigger one??Thx

Ujoints are easily swapped and there are combo joints that work great. I would be more worried about the correct length myself.

Are you sure the rear one was small?

Some 340 cars (including AARs & T/As) had a little one up front & the big one in the rear.

What Stump said, I'd get your rear axle up on stands (so it is loaded) & butt a yoke all the way into the trans & measure the C to C you need (that length minus 5/8-3/4). If good there then the combo ujoint & you're all set

Does your rear yoke take the big joint or small? Honestly? Unless he wants a gazillion rollars for it or you are doing a correct restoration, put an adapter joint in it and call it a day. The small u-joints are pretty tough.

I pretty sure 70 and later a-body's used the small joint. I got a 72 with the small joint (3 speed).

[quote=cudaman1969]I pretty sure 70 and later a-body's used the small joint. I got a 72 with the small joint (3 speed). [/quote

I need it for my 71 cuda. Yea I'm sure both top and bottom where small joints. He wants $200 for it so he's not giving it away. I don't mind paying it if it's *correct" for the car. I don't want to put it in or buy it just because it fits!

If you located in the archives the C to C dimention for your vehicle and his shaft matched that then it would be a correct one. I would tho mock something up & see what C to C you need (you do have a bit of leeway) just for reference no matter what choice you make. Not sure if yours' came with 7260's or 7290's & as you know a pig change somewhere down the line could have changed that (7260/7290) too on the rear end of the shaft for the ujoint needed

Sorry it's not for sell, just using for example. You say 71 Cuda? That would be a big joint, e-body, thought you where talking a-body. That would be right at 44 inches and change, cup to cup, 3 1/4 diameter necked down at the back.