kyle b

Hey everyone. I have a 2000 Jeep Cherokee Sport with a 3" suspension lift. Recently I have heard a vibrating sound coming from underneath the vehicle when I go 60MPH or faster.
It makes a loud vibrating/grinding sound but I do not know what it is. Also, when I am stopped and I take off quickly I hear a grating sound coming from the rear end and I feel it vibrate.
Can anyone help me out as to what this problem is please?

COSXJFAN

Moved to tech, wrong section...

jfiedler

could be bad driveline u-joints, probly caused from the increased driveshaft angle.

dukie564

you likely need to add a SYE kit and double cardan drivehshaft (common for even a moderate lift on late model XJs), or fix your pinion angle.

With a single U-joint at each end of the driveshaft, the pinion angle MUST be parallel with the transfer case output, so each u-joint cancels the vibes from the other.



If you have a sye and a double cardan at the transfer case, you point the pinion directly at the transfer case so you have 0* difference between the pinion angle and driveshaft angle, meaning your pinion is pointed higher

warthog

You can try a TC drop and or shim the axle under the leafs

jeepxj19

u dont need a sye for a 3 lift, just get a tcase drop or shims in the rear, before that check the ujoints first

no rdplz

You don't need an SYE for a 3" lift. All you need is a 1" t-case drop and/or axle shims. I did a 3" on my 99 and all I needed was the t-case drop. Check your u-joints, you may want to replace them anyway with some higher end ones just to play it safe. They're easy to change out so I'd go ahead and do it just to play it safe.

Skunkape

Yeah try a tcase drop first......every Jeep is different but you should not need a sye at 3"

kyle b

thanks. I am putting some degree shims in the rear end above the leaf springs so i will see how it all goes....

warthog

try 6 degree shims

TrekkerJmm

Same exact problem after I installed my 3 inch on my 94. I dropped T-case and put in shims then the Vibs went away...Tj

kyle b

Hey guys, I just got a pair of 4* shims put in the rear end to try and stop the vibrations that were going on and it seems like it just got worse or didn't even do anything so does anyone else have any advice?? Im lost as to what to do to fix this problem....

dukie564

This is the solution to your problem. You need to put the shim UNDER the leaf spring, thicker end toward the rear.

alloutperform

also make sure your ujoints are in good shape.....your increased angle could be causing them to make noise because the are flexing outside of their normal wear pattern...happens alot