'00 XJ noise/vibration (like a tire rubbing)

I recently completed a complete (pads, rotors, hoses and calilpers) front brake job on my '00 XJ and it drove fine for several days, but recently I have began to experience an occasional noise/vibration that feels like a tire rubbing on a fender or control arm. It first happened going around a turn, but now can be occasionally heard/felt when turning or going straight. It will clear up completely on it's own and most of the time there isn't the slightest hint of an issue. She runs smooth, straight and vibration free down the highway and when on the brakes.

I'm on the stock suspesion w/ 249K running 235/75R15 General Grabbers and there is no rubbing. I've looked around underneath and can find anything out of place. I initially supsected something in the steering since the first occurrence was coming out of turn. I check the fluid and found it low (wasn't makeing any strange noises or whining at all), so I drained the reservior and refilled with fresh fluid of the proper spec. It was fine for a day after that, but then it happened again a few times yesterday. Seems like it will only do it after it's been running a while on a hot day. So I haven't ruled out a power steering issue yet, especially since I dont' think the fluid has ever been changed.

Other than a quick look underneath and the ps fluid change, I haven't looked at anything else. I know I need to check the rear brakes and probably change the shoes, so it could be something there. I was just wondering if anyone else had ever experienced a similar noise/vibe (based on a rather vague description provided) and could comment on whether or not you found the cause...or just had suggestions on other things to look at. The drivetrain is 100% original so it could be any number of things I guess.

Thanks.

Did you use longer brake lines in prep for a lift? They could rub the inside of the tire if not held away with a spring.

I'd bet you have a wheel bearing going out. Sometimes it will have play if you jack it up and shake the wheel. If it's more noticeable on turns, usually the loaded tire (outside of corner) will make the noise. Ex: if when driving you turn left and it groans, but not when turning right, it's probably the right side bearing.

Thanks guys. I'll check those things out.

I used stock length brake hoses from Napa. I didn't measure them so I guess there's a chance one or both could be longer than what came off. It wouldn't surprise me given the poor quality on the new Napa pads and calipers. Their stuff has really suffered...

I'll get the front end up in the air and check the wheels for play.

Thanks again for the advice!

Did a little investigating over the weekend. Checked the brake lines and they are definitely not rubbing on the tires, so scratch the easy solution. I also jacked up each front tire to check for play in the bearing. Couldn't detect any movement when pushing/pulling on the top and bottom of the tires, but spinning each did produce a rumbling noise that I don't recall hearing back when I did the brakes.


Passenger side

https://www.youtube.com/watch?v=GThZ_RqcXs4

Driver side

https://www.youtube.com/watch?v=W0X2XBUVxo4


I need to check the front gear lube level, but do these noises sound like a wheel bearing(s) problem or possibly something in the diff itself?

Gear lube level was fine and it is was as clean as the day I put it in, so I don't think anything is wrong inside the diff. I also seems to me that if the noise (in the videos) were related to a bad wheel bearing, the chances of both going bad at the same time are pretty slim. I could be wrong though...

I'm going to check the front driveshaft next for play in the joints.

Since first hearing the noise/feeling the vibe, I've done two drain/fills of the power steering fluid and while it does seem better, it hasn't completely gone away, so I don't think it's related to steering.

Unless a bearing was really bad you would feel, but not likely hear, a roughness in the rotation. A truly failed unit-bearing hub makes an almost constant noise when you are driving.

In the video, "front wheel, driver side", What is the sound at about 0:03 to 0:06 ? Sounds like an axle shaft u-joint to me. If you are disassembling to replace a unit-bearing hub, you should install a fresh u-joint at the same time.

Hubs are not that expensive, I replace them in pairs especially if they are know to be the same age/mileage.

Tim_MN said:

In the video, "front wheel, driver side", What is the sound at about 0:03 to 0:06 ? Sounds like an axle shaft u-joint to me. If you are disassembling to replace a unit-bearing hub, you should install a fresh u-joint at the same time.

Hubs are not that expensive, I replace them in pairs especially if they are know to be the same age/mileage.

Click to expand...

I'm not quite sure what that sound is, but both sides did the same thing. I crawled underneath last night and didn't notice any play in the front driveshaft u-joints, but didn't have time to look at the ones on the axles.

Did some more checking last night and I think it's the u-joint(s)...

The first time I looked at them I just grabbed the driveshaft, attempted to turn it and looked for play in the joints. The time I grabbed each yoke and tried to wiggle it in all different directions.

Driver's side did this...

https://www.youtube.com/watch?v=EEItiLDoXPE

Passenger side did produce a similar noise, but wasn't as pronounced and is not really noticeable in this video...

https://www.youtube.com/watch?v=AbDc8H51xWE


So it seems I have at least one bad u-joint...and if I'm going to replace one, I might as well do them both and stick new unit bearings in while it's apart. That being said, I have the Jeep casually for sale on my local craigslist with full disclosure and I do not intend to fix this if I continue my efforts to sell. If I decide to keep it and dump my '15 Tacoma for a commuter car (which I'm very tempted to do), it will need to be addressed sooner rather than later.

I don't think this repair is beyond my ability, but I am somewhat concerned with how the 250K mile seals will hold up to the shafts being pulled out and put back in. The last thing I want to do is spend $150 to $200 doing the u-joints and bearings and then 500 miles down the road, have to pay someone to do the seals (that IS beyond me and I've read it's expensive). Anyone care to comment on that?

Thanks.

If that is the u-joints making those noises they are toast.

If you work with care and use proper techniques, the seals will be fine. The biggest mistake people make is vigorously stabbing the axle shafts back into the axle tubes and damaging or knocking the seals out of place. The axle shafts must be gently guided into the tube until they touch the seals. Then, still gently, maneuver the shafts until they enter the seals.

Thanks for the advice Tim_MN. I really appreciate it.

You recommended replacing u-joints if going in after the unit bearings. How about the reverse? Should I plan to the do bearings if I'm targeting the u-joints? My gut says 250K so go ahead and refresh it all...

I'd bet on the transmission mount. My jeep started getting a vibration from a take off, and I could've swore it was in the front end somewhere. Someone on another forum suggested it, and sure enough, that was my problem

Got the hubs out and axle shafts pulled over the weekend. For the most part the hubs and u-joints seemed smooth and tight, but after flipping the shafts around a few times I did start to get a squeak out of one of the joints.

Now this might be a dumb question, but is it ok to spin the carrier with no shafts in the axle? I'm still a bit paranoid about the noise each side was making when I spun the tires by hand and I would like to see if I hear anything similar by turning the front drive shaft now that the u-joints and hubs are out of the picture.

Thanks.

Yes, spin away.

Started tearing into this a few weekend ago. After I took the nuts off the ends of the axle shafts, for some reason I gave a little push on the end of each shaft and they both very easily slide farther into the axle. I figured that was good as it showed that they were stuck in the hubs. However, after I got the hubs off and shafts pulled out, I realized that little push forced a slightly rusty surface on the each shaft into each axle seal. That made me paranoid, so I decided to go ahead and replace the seals too.

Popped off the bearing caps, pulled the carrier and found this yesterday...

Pass side.






Driver side






So it looks like I'll be replacing the inner bearings as well. I'm now questioning whether or not to also pull the pinion to give it new bearings and a seal too...

The kicker is I need this thing back together soon and I only get a few hours every week to work on it. It was a third vehicle, but will be needed for daily driver service in the not too distant future. I'm driving a VW TDI right now that I'll be turning in as part of the buyback and I don't want to rush into buying something else. That being said, is there any reason I can't pull the front drive shaft, plug the axle tubes, reinstall just the unit bearings and run it as a 4x2 until I have a chance to fix it properly?