Lowering pinion instead of t-case drop ?

Yup, I searched, but did not find a clear answer. And don't tell me I need a SYE, no money for that right now, thanks.

I lifted the 2001 XJ 2 inch via longer shackles, and I got vibes, I know about the 1 inch t-case drop, but I was thinking about lowering the pinion instead, I want to know if it will work better or with equal result than the t-case drop ??

The jeep was aligned, and drive straight. I got the "klunk" from the t-case now, I'll have to grease it.

Any opinion ?

So, you want to add more angle to the driveshaft?

lowering the pinion would increase the angles on the driveshaft. if anything, you want to point the pinion up.

but also, part of the reason for a SYE/tcase drop is to to shorten the distance. the vibes comes from the fact that there's not as much contact between the splines on the tcase output and the driveshaft. geometrically this happens because when you lift the jeep, the axle effectively gets farther away from the case but you have the same driveshaft that's trying to cover that now-longer distance.

i know you said you can't afford it... but there really is no better way to do it than the SYE. i'd do the tcase drop for now and then start saving pennies.

HTH...

edit: that's what i get for typing a long post, mark beat me to it...

I did not think about the added angle on the joints.....sorry about that.

:doh:

I'll just drop the t-case for now and see

Thanks

You mean raising the pinion...right? Lowering it will make it worse. You can install shims, probably only 1* or 2* shims, to help correct the geometry.

i wonder how long it will take for the stock rear springs to sag with a 2" lift shackle?

Lift shackles raise the diff pinion, taking it out of phase with the t-case pinion angle. You need both pinion angles to match on a non-CV driveshaft, so you'd need to lower the diff pinion angle IMO. Buy a pair of 2 degree shims and put them in fat side forward, tighten everything down and test drive it. If the vibes go away, you're good to go.

fubar XJ said:

Lift shackles raise the diff pinion, taking it out of phase with the t-case pinion angle. You need both pinion angles to match on a non-CV driveshaft, so you'd need to lower the diff pinion angle IMO.

Click to expand...

I agree with this, however you should be leaving the pinion and dropping the t-case since the driveshaft will be too short and the u-joints at too extreme of an angle if you lower the pinion.

The angles of the two u-joints (t-case output and axle yoke) should cancel each other out.

http://www.4xshaft.com/techinfo.html

Believe you will need a combination of TC drop and some shims to correct the pinion angle....and yes, the pinion does need to be pointed down slightly so that the output shaft of the TC matches the pinion angle.

Depends on how much the pinion rotated.

I've never even heard of a 2" lift shackle...?