Swapping 904 to 727

[dart6]

Hi got a few questions that hopefully i can get answered. I have a70 sport satellite 318/904 that i want to swap out for my 408 SB/727. Do I need a different trans cross member. I am going to put a 8.75 axle in as well. I am having difficulty finding suppliers for the rear uni crosses, can anyone steer me in the right direction would be much appreciated if i can get the answers.

 

[sawdoff]

Doing the same. First the 727 has a different yoke. 904 is smaller. Any 727 or 4 speed yoke should work (so i was told and the one he sold me fit). Also will need a different dust shield. Cross member went in fine. Havent bought the u joint yet but think there are only 2 small and large??? OH your drive shaft will be different. I think the one you have could be cut down. They are also making a joint that has a small and large side so you can keep your shaft (but if youre making lots of power that may not be a good idea.) If you have to have one made should probably go with the larger u joint.

 

[dart6]

phew that was quick and to boot you're doing the same thing. I already have the slip yoke .So are you saying my cross member as it is will work fine.

I will get a stronger shaft made here but need to find a source for the cross joint that welds onto the shaft and joins to the big 8.75 yoke.

Any sources to point me to

thx

 

[Big Jim]

NAPA stocks the 7260/7290 conversion u-joint you need (at least in AZ) give me a bit & I'lll see if I can get a part#

 

[sawdoff]

The part about "welding the cross joint to the shaft" concerns me. Are you talking about the u joint?

And if you need a new rubber mount get it from rockauto. I paid about $2 each on motor mounts and tranny mount.

 

[Big Jim]

Mopar # for combination u-joint is P5007418, Neapco # is 11-726090. Should be able to cross over at NAPA (just find a counterguy that's been there a while...lol)

 

[dart6]

Thanks for the replies i'll follow them up.
The cross sits in the piece welded to the shaft

 

[67 B-body]

Thanks for the replies i'll follow them up.
The cross sits in the piece welded to the shaft

I'm lost.....
You have the driveshaft tube, with the front and rear ends welded to it. The U-Joints press into the ends,,,, What is the cross??

 

[Big Jim]

Thinking he's referring to the spider of the u-joint itself...

 

[oxytousc]

Yeah, I think Big_Jim is right. He's just talking about the driveshaft end where the u-joint is located. Once it's cut to length, it will have to be rewelded and rebalanced.

 

[dart6]

yes that is correct thx