XJfan29

I recently had my xj lifted by a shop that is supposedly experienced with after market mods to trucks/suv's. I have a lingering issue. I hear a low pitched loud rumble past 30 mph or so. Sometimes i think i can hear gears whining, but not sure. Seems a little "off" and i am afraid i might be doing damage to output shaft or diff.

Vehicle specs:
98 xj, 4x4, auto, 4.0

Mods:
Slip yoke eliminator, replacement drive shaft, 3 inch lift. Still running stock tires until i get this squared away.

Question:

Is it normal for excessive road noise/rumble after installing sye? This sound is roughly equal to the window being down. It doesnt matter what the engine rpms are. Some gears sound slightly better than others. Using the transmission to brake (not downshifting just letting off the gas) seems to be louder. I havent tried 4 wheel drive yet. I literally got home with it an hour ago. I have already complained once, and they seem to think it was no big deal.

I would appreciate any help, thanks!

99superjeep01

Take the rear driveshaft out and drive it in 4 wheel. If it doesn't vibrate there's your problem. Just don't take any sharp corners on the pavement and you'll be fine. I've had a dry u joint in my axle cause a vibration like that.

XJfan29

Sorry, the sound is a rumble like noise. I dont think it vibrates, except maybe when i let off the gas past 50ish. Could it still be A dry u joint? They are both new, replaced with driveshaft. Is it possible for it to be dry from the factory?

Tom95YJ

Bad pinion angle

XJfan29

So they didnt shim it properly?

Tom95YJ

Could be the issue I had that issue with my Xj so I installed degree shims and it went away

Jeepxj1234

You want the axle to be pointed toward the transfer case if I remember correctly.

DieselDaze

Betcha they'd think it was a big deal if you didn't pay them.. matter of fact if you paid with a credit card I'd let them know they can fix the shimmy before I dispute the charge...

a reputable shop at the very least would request you bring it by for a test drive...

XJfan29

I drove it today to work, and there is definitely a slight vibration even a low speeds. I am leaning towards the pivot angle. I plan to try it in 4H today, just to make sure there are no surprises there before I decide what I am going to do.

That ship has already sailed. That is part of the problem, this lift and sye took about 2 months to install and get the parts. Extremely frustrating that it wasn't right the first (or second) time. So naturally, the credit card bill was due and paid.

XJfan29

Update:

Talked to shop manager on the phone, he insisted that the sound i hear are the tires. There is some tire noise, but this sound is not from that.

I tried the four wheel drive on a gravel/dirt road next to my house. Engagement did not feel "smooth" so i tried 4 low. 4 low no longer works, the transfer case never switches out of neutral. I suspect this could have something to do with the noise....

Tom95YJ

If you have stock wheels and tires or know someone who does put them on your Jeep then drive it to the shop if it still makes the noise so you can have them fix it