KChiefin29

Hi, I just recently installed a rough country 4.5" xflex lift with transfer drop....doing sye and ds in 2 weeks. Anyways, today is the first time I got her on the highway and started hearing a droning or buzz/hum sound when I press on the gas. The sound is oscillating - and the droning or what not gets faster as the car speeds up. The noise is not apparent or as apparent when coasting. Anyone know what could be causing this and is it something that needs immediate attention?

Anyways, I had the lift installed and they were not able to get the upper control arms in. Reason being, we need new uca bushings (the ones on the axles) and needed them mailed in I was told. Anyways, I did not want to leave the car for over a week.

My guess is that the lack of uca is causing the front axle to be pitched weird...causing a chain reaction to ds etc...but, I am in 2wd and it only happens when I give it gas on the highway...Or...wheel bearing?

Thanks in advance



Also posted this in the lifted questions thread.

xLxDIZZYx

Did u install new tires

KChiefin29

Yes, new wheels and 33x12.5 general grabber at2....so it's just tire noise lol? If so I feel dumb....

KChiefin29

As I gave it some thought...the sound doesn't seem like tire noise as I can hear that...and it's a diff noise...but nothing that concerns me.

Still...it could be the tires but who knows.

rctrav

So what your saying is your running no UCA??? Right now

RubberSideUp

Post a video.

KChiefin29

Ha sorry...the factory uca's are in there for now. I'll try to post a video of some sort.

I'm hearing that it may be wheel bearing or u joints....

Red82

If it's an oscillating sound it could be hubs but my first question is fid you get it aligned after you lifted it?

KChiefin29

Yes, alignment, mounting, and balance was done at the shop.

Red82

Cool. You'd be surprised how any people don't get an alignment after they lift it. I don't think hubs would be that loud. Could you take a video and let us try and hear it?

98cherokee531

That sounds like the rear driveshaft to me. I have about 4" in the rear of my xj with the shorter 5spd tranny. 1" t case drop and around 50mph in 3 or 4th gear it hums a bit. Grab the 4wd lever while you hear the noise (do not engage just touch the lever please) and see if it vibrates and matches the humming you hear.

KChiefin29

I tried to post a video lastnight, but when I transferred them over to my pc....no sound!

Anyways, when playing the videos on the phone....I couldn't even hear the humming or buzzing in the vid when watching it on the phone....lots of road noise and background noise...windows were up and radio off. You can almost feel it in the whole car...but its barely there.

It may be the rear driveshaft...the sound isn't super loud or anything...its definitely oscillates and it's like a buzzing or hum....not really noticeable until I'm going 50+ and when my foot is on the gas. Though the sound did not seem audible on the camera/phone....I can def hear it in the cab.

How do I know if I have bad U joints? I hear that they rarely go out...my cherokee has around 118k...also...I'll be doing wheel bearing and hubs soon and was wondering if I should go ahead and do the U joints...FYI...never done wheel hub/bearings and/or U joints.

Red82

Hubs are pretty simple just make sure you have the right tools.

Usually if it's your drive shaft u joints they chirp like a bird when they go bad.

KChiefin29

I wanted to mention that I can somewhat shake or move the DS around the joint closest to the transfer case....It is a very slight movement.

Is this normal?...or should it not budge at all. Sorry if that's a dumb question...

98cherokee531

It will move slightly because of the increased angle when the vehicle is lifted. Bad u joint just lay under the vehicle while its in neutral or no load on the transmission. Grab the driveshaft and twist it back and forth and if its sloppy at any u joint point, it's time for new ones