Help! Still Have High Speed Vibes....

[woodkrawler]

My 99 XJ has a 3" OME lift and i ran a t-case drop forever without any vibes but i finally was able to do the RE hack-n-tap and i used an XJ front DS and some 3* shims to put my pinion within 2* of my DS. The jeep drives and rides great until you reach approx. 68+mph then the vibes set in. They aren't terrible, just very annoying. It comes and goes with varying RPMs, worse as you accelerate. Im 99% sure they are coming from my driveline but i can figure what else it could be. the U-joints seem tight as well as the CV and now its shimmed correctly.

Could the DS be out of balance? Is there anything i can check for? Any suggestions would be much appriciated!!

Thanks
Lincoln

[BillR]

Pull the front driveshaft and recheck it. That will narrow it down to an area.

[woodkrawler]

Pull the front driveshaft and recheck it. That will narrow it down to an area.

Ill try that but im pretty sure its coming from the rear. It didn't vibe until i did the SYE.

lincoln

[FUNKYTEE5]

[QUOTE=woodkrawler]My 99 XJ has a 3" OME lift and i ran a t-case drop forever without any vibes but i finally was able to do the RE hack-n-tap and i used an XJ front DS and some 3* shims to put my pinion within 2* of my DS. The jeep drives and rides great until you reach approx. 68+mph then the vibes set in. They aren't terrible, just very annoying. It comes and goes with varying RPMs, worse as you accelerate. Im 99% sure they are coming from my driveline but i can figure what else it could be. the U-joints seem tight as well as the CV and now its shimmed correctly.

Could the DS be out of balance? Is there anything i can check for? Any suggestions would be much appriciated!!

Thanks
Lincoln[

If it was imbalance it would most likely vibe in relation to driveline speed regardless of load. Have you checked to see how much axlewrap your getting? Mine vibes under load also due to axle/springwrap. Maybe try some different shims and rotate the pinion down some more to compensate for load conditions. Also, does it vibe/throb a lil under acceleration at lower driveline speeds? Just some thoughts:) Good luck.

FUNKYTEE5

[BrettM]

did you use all new u-joints?

I've seen 3 different vehicles, 5 different times, get vibrations from changing the angle on a driveshaft while leaving the joints. all 5 times replacing the joints eliminated the vibrations. always replace all your joints if you change the angle on your driveshaft.

[DrMoab]

did you use all new u-joints?

I've seen 3 different vehicles, 5 different times, get vibrations from changing the angle on a driveshaft while leaving the joints. all 5 times replacing the joints eliminated the vibrations. always replace all your joints if you change the angle on your driveshaft.
Stole my thunder Brett...I was also going to say though that yeah it could be out of ballance....Just because you don't feel it below a certian speed does not mean anything.....Driveshafts do very weird things.

[woodkrawler]

thanx for the help guys, im going to have it balanced and i replaced 2 out of the 3 u-joints but i might replace the 3rd one too.

lincoln

[xjaddiction]

did you try taking your front d-shaft out and putting it in the rear (leave out front d-shaft)?