diff conversion

[Obsessed]

Hi guys I have a 72 duster with a 904 trans im changing my differential from a 7.25 to a 8.75 how much should my driveshaft be shorten by to suit the 8.75 diff
Thank u

 

[krazykuda]

About 2", but call your driveshaft shop and ask them how to measure it, so you do it their way and it comes out right....

My local shop says to shove the front yoke in all the way to the rear of the trans and measure from center of u-joint to center of u-joint in the rear and then subtract an inch for installation.