Drive shaft lenth with 4" lift?

[Doc1993]

Have been planing to do some work on my "X" for along time, and am now in the position to do it. I have a 93 2dr. So my questions for now are: Would I need longer driveshafts if I install a 4" lift? And if i do Would the shafts from a 4dr be long enough for this lift on a 2dr?


Thanks.

Daniel

 

[Four0Sport]

my 93 2dr has a slight vibration that im attributing to the driveshaft while under light acceleration. vehicle has rear lift springs and extended shackles. the rear is actually a slight bit taller than the front, i am going to put the stock shackles back on to level it and see if that helps with the driveshaft vibration. the boot is still on the slip yolk on the front of the driveshaft and is not stretched out fully so there should still be room there for it to adjust. I think my problem is with the angle of the rear differential and the age of the u-joints.

 

[rustbucketMI]

think my problem is with the angle of the rear differential and the age of the u-joints.

Any time you do a lift, or a drop, the angle of the output shaft of the trans, relative to the input of the diff, will change. When you lift your truck the nominal angle changes. This results in the u-joints having more stress and the drive shaft to slip more on the slip yoke. This caused vibration. Usually when you lift your truck a good deal you will have to replace the drive shaft with a longer one. As well you should change the angle of the diff to the stock angle. Most aftermarket kits will come with a shim of some sort, usually its only a couple degree shim.

Without this shim modification you will usually notice more vibration on the drifeshaft, and your u-joints will wear quicker.

 

[JDraper]

I did a Superlift 5.5 on my '94 Sport and didn't need longer drive shafts. The stock ones worked just fine. If you go above that, or set it up for extra travel in the suspension, you will need a longer driveshaft shaft.