I am rebuilding a 1970 Cutlass convertible, and switching from the 350 engine and turbo 350 trans over to a 455 with turbo 400. I bought a new yolk for the driveshaft and test fit it OK to the turbo 400. Here is the problem. I purchased a AC Delco front u joint part #45u0106. that u joint does NOT fit into the new yolk. When I took the bearing caps off to fit it, it just doesnt clear the yolk ends like the u joint is slightly too long. ???? Any ideas?

 

Can you post a picture, some clips go to the inside on the caps instead of the outside yoke groove.

 

Are you sure you got a Olds yoke, and not a Chevy?

 

Im not sure about the yolk. I think I bought it from the parts place a few years ago. What's the difference between the chevy and olds yolk? This can be the whole problem. My car is a 1970 cutlass cv came with 350 engine and th350 trans. original non posi rear end. I replaced the engine with 455 ci. 400 turbo and rear end with o type posi. I took the drive shaft to the local mechanic to have the parts place yolk installed with new delco #106 u joint. He called back and said that u joint wont fit. I went there and He showed Me. When He took off the bearing caps it wouldn't fit into place like was too wide? He put on a different u joint and it worked. So I take the drive shaft back home and tried to install it. Slid it into the tranny and then it wouldn't fit the rear end like the shaft was about 1/2 inch too long. Sorry to write this into a story but just trying to explain. It seems the best solution would be to cot off 2 inches off the yolk, but I really don't want to try that.

 

How deep is the yoke in the transmission, some 400 have an o-ring on the output shaft that need a counter bored yoke.
did you measure to make sure the drive shaft was the correct length with your combination?

 

Turbo 400 yokes are not that long, post a picture of yours.

 

I took the driveshaft and yolk(already assembled) to a driveshaft shop today and He is going to shorten it from 56 1/2 " to 55". That should be enough to allow for yolk movement in the tranny. Hopefully this works. THANKS!