Driveshaft question ???

[22dog22]

I am getting close to reinstalling my driveshaft i have replace the 7-1/4 open rear with a 70 duster 8-3/4 possi rear, i will be using my 904 trans. That came with my 69 cuda with a 318 engine, i know i will need the driveshaft shorten, but will the rear yoke/u-joint fit the 8-3/4 rear now??? Or will the driveshaft company that shortens the shaft need to replace the rear yoke ??? Any thoughts???

 

[fishy68]

Should fit. Almost all A-bodies used the 7260 U-joint. I think only big block cars used a 7290 U-joint. Even if the rear does have a larger 7290 U-joint you can use a conversion U-joint that has the smaller 7260 size one direction and larger 7290 size the other direction. Or you can change the yoke if you desire, but that'd be quite a bit more costly.

 

[Supershafts]

When you see your driveline shop they'll tell you what to measure and from that they'll know which joint you have and need.
If you need the 7290 series i'd tell you to change the weld yoke now to the correct size so you don't need to worry about conversion joints, which are being deleted, spicer has stopped making the 60/90 joint and the only others that are worth while are Rockwell and Neapco which are going to wind up getting in the $60 area soon or more.

 

[22dog22]

thanks for the information I will follow up at my local driveline shop.