Bad u-joints?

[JeepXJ93]

Started happening immediatly after doing the 3" lift...thought that it was just driveline vibes...but aside from those, whenever i'm on the highway anwhere from 45-65....for example if i had to take an exit soon as i start letting off the gas maybe for a few seconds i hear this horrible vibrating sound. Also happens if i were to slow down from highway speeds to coast for a min and then as soon as i start to accelerate again it would happen for a second or two....sounds like its coming from somewhere towards the back end of the jeep. I've realized also that once doing 55 if i hold on the gas just slightly to keep my speed from dropping the noise/vibe would stay constant. Would this have anyhting to do w/ bad u-joints?? Anything in the diff. maybe? Thanks for any help.

[paulhead]

What your pinion angle look like? I think within 3degrees is tolerable. This is what my YJ looked like after 4" WITH a T-case drop kit. You having a longer driveshaft it may not be as bad but enough for vibe. I ended up getting a SYE and longer driveshaft and still had to shim my axle 8 degrees.

Also get under neath your jeep, grab the DS at the pinion a see if you have alot of play, bad bearings/seal?

[aston]

you-jay

U/Js are relatively cheap. You might just want to change them if you have any doubts: easier to do in the garage than on the trail.

Tom Woods makes good DSs and now he has U/Js as well http://www.4xshaft.com/

While you have the rear DS off, take a spin with FWD and see if the noise has gone.

Also, U/Js need lots of grease and often.

Chris L.

[paulhead]

Yea thats what I got the Tom Woods SYE and drive shaft.