vibration at high speeds

[FL. 2001 XJ]

After installing 3.5 rubicon express lift I have been trying to track down vibrations. First installed trasfer case drop kit. Still had big vibrations. Then I installed sye with cv drive shaft and installed 4 degree shims. Vibrations were gone on acceleration and deceleration. From 0 intill about 60 the jeep has never felt better, but after 60mph I have a pretty good vibration. Its constant. decelleration or acceleration does not effect it. The faster I go after 60mph the worse it gets. I appreciate every ones comments
just trying to get rid of these vibrations

 

[JAGER]

Double check your rear yoke nut. I didn't have mine tightened enough and I would get vibrations at 66 MPH+. You may want to remove your front driveshaft and see if the vibrations are still there with it removed. Hope this gets you in the right direction!

 

[matchrocket]

I am fighting the same issue right now. Yanked my front DS and its gone. U-Joints are probably getting tired.

 

[FL. 2001 XJ]

Double check your rear yoke nut. I didn't have mine tightened enough and I would get vibrations at 66 MPH+. You may want to remove your front driveshaft and see if the vibrations are still there with it removed. Hope this gets you in the right direction!

Thanks for reply. I will take the front drive shaft off and drive it. I was going to try that but, I just didnt know it that was a good way to diagnose a front drive problem

 

[matchrocket]

Thanks for reply. I will take the front drive shaft off and drive it. I was going to try that but, I just didnt know it that was a good way to diagnose a front drive problem

I guess I should of been a bit more specific. Do you have a non-disco front D30? Part time 4wd option? If so its spinning, but not under power, while driving down the freeway.

 

[builder]

you installed a 4* shim after you took the D/S and the pinion angles? and is the pinion now 1-2* lower than the D/S. if you didn't take readings of both you may have the wrong shim in.just a thought....

 

[Talyn]

Possibly unbalanced rear shaft is what it sounds like to me.. I know its a new shaft, but it happens.

 

[FL. 2001 XJ]

thanks for all replies. Took the front drive shaft off. Now I have no vibrations.
I have some play in the slip of the shaft. I am taking it into a drive shaft shop. I have herd of problems with Lp differentials I that isn"t the problem.