I have a 2000 XJR that has an interesting vibration/noise.

It sounds similar to very excessive road noise, or like an engine that never shifts, but it's neither of those things. The pitch of the noise goes up with speed, not RPM.

I've replaced bad rear wheel bearings. There doesn't seem to be any play in the front bearings, though I haven't ruled them out completely at this point, as the vibration/noise seems to be originating from the front of the car.

The wheel alignment has recently been done and then was re-done after replacing the rear bearings.

I've replaced a bad passenger side engine mount.

The interesting thing to me is that if I take a long hard right turn at speed (enough to cause a noticeable sideways G-force) the noise goes away for the duration of the turn, but not when turning left.

Any ideas?

I just passed safety and emissions today. My next step is to get the fluids all changed... I could use an oil change right about now anyway.

 

Since you've already changed the wheel bearings the are at least two things to consider. One is a bad tire. Try switching the tire rear to front to see if you notice a difference. The other item is the axle bearing on the diff itself. I had one fail on an X300 and it acted as you describe. It's not easy to check as I think you'll have to pull the drive shafts and check endplay on both axle stubs. There should be a preload so any movement is too much...

Good luck!

 

Not a tire issue either. That was actually the first thing I replaced trying to figure out the issue. All new tires. I should've mentioned that in my the original post. My bad.

 

Ok, so I just had my fluids changed and they told me I have a transmission leak.
I asked about it and they say it's a dealer only thing to even check the fluid... that it doesn't even have a dipstick.

Sure enough, I checked under the hood and it has the cap with no dipstick attached that notes that only Mercedes Benz should service it. Ha! OH Greeaaat...

I think I should look into this issue before I go any further searching for bad bearings. I'm hoping it's not a huge deal, but it needs attention regardless.

Now, the hard part... I don't want to risk harming the transmission, but is there an aftermarket dipstick for these things and do we know what type of fluid it requires? Or do I just pony up the cash and take it to a dealership?

Have any local (Utah Valley) XJR owners dealt with this?

 

The dipstick is available on ebay or online tool dealers. Or make your own and read using the depths posted in pictures in other threads.

If it is leaking, it is likely the collar where the wiring harness enters the transmission, well known problem, easy and cheap fix. At the same time, do a fluid and filter change.

Any Merc dealer has the collar and filter much cheaper. They stock the newer redesigned collar.

 

Gille - the noise, and disapperance of noise when turning in 1 direction only certainly sounds like a front wheel bearing. On my car it was the front driver's side that was bad. After repalcing it the noise was gone

 

I have a similar noise and a mechanic buddy helped me and we think it is coming from the differential.

After reading this post could it be the output bearings and not the differential?

We check the fluid and the level was fine but the color was dark, but didn't smell burned.

 

I think I'll find someone with a lift or a dyno so that I can run up the rear wheels to see if I still have the noise while the front wheels are stationary... if the noise isn't there, I guess it'll be time for new front wheel bearings.

 

interesting and timely for me as well....but not on my jag, on my toyota tacoma.....i get the humming noise.....and the noise intensifies the faster you go...did some research ....and of course points to wheel bearing as you mention.
i also have BEEN FOOLISHLY DRIVING MY TACOMA WITH BAD BALD TIRES....got bad scare...with last snow storm....so i just got a new set of toyo's open country tires....will be interesting to see if noise goes away with new tires on the front....but i think not.....i probably will need wheel bearing job and new pads after all is said and done as well.....

funny thing the noise/humming seems to lessen to a barely audible level when the temperature goes down to the 20ies....as temperature outside increases the noise returns louder.....anyone have an explanation for this phenomena?

good luck with your repair/fix....i will up-date on mine....

 

I had the car into 2 different tire shops today, one was just where my brother's friend works. He messed around for a bit and couldn't find anything more than an alignment problem, and we noticed significant tire wear on the outside of the front tires, especially on the right.
So i took it back to the shop that I got the tires from... took one of their guys on a drive to hear the noise. They rotated the tires, threw some new front brakes on and did another alignment. front right was about 30 degrees out of spec. Drove it home and the noise was still there, so I gave them a call and I'm taking it back tomorrow. The tire wear and mystery noise continue... ughh...

 

I am with Rocklandjaq. Front wheel bearings. I was hearing noises and burning up outside of front tires. Just my experience.

 

up-date...as per my tacoma- new tires on the front and replacing front pads...got rid of the noise.....but in your case i still think....wheel bearing issue....keep us posted on progress and good luck...

 

I called up the tire place this morning and told them I'm taking it to a real mechanic... Someone that I trust won't send me out the door without actually verifying that they've fixed the problem.

I took my mechanic on a drive and he said he's almost positive that it's a bad wheel bearing.

He also emphasized that after he confirms his suspicions and replaces it that I need to take it back as soon as possible to the tire shop that I got the tires from and get an alignment through them and talk to them about warranty on the tires and how they missed the issue after taking it back to them numerous times which caused unnecessary tire wear on some expensive tires.

He's always looking out for me... I don't know why I didn't just take it to him sooner. I'll have a quote and the exact cause later today.

 

Turned out to be a bad front bearing and lower ball joint. All fixed now

 

Good to hear Brandon.
There's nothing worse than being led a merry dance by shysters who call themselves professionals!
If you are not mechanicly inclined, you don't mind paying that little extra if
you know you are going to get a good job done by a true professional and not some jumped up grease monkey!!

 

Had the same thing happen; front wheel bearings.

Replaced them both. You need(ed) a special socket tool; I found mine on eBay, but it was from an outfit in Texas that had the best price, $150 or so.

I used it, and then sold it on eBay for $125, a pretty fair deal - I hope it's still going around.

 

Yeah, I had read the procedure on how to do it before my mechanic got back to me with a quote and decided to dish out the $380 for the front wheel bearing and lower ball joint replacement. Seemed to be the better deal for my financial situation.
Thanks!

 

You did well.

 

Is it because when its cold you drive round with the window(s) wound up ? lol

 

I'm still getting very excessive outside feathering on the passenger side front tire. Possible issues? It's always the front right tire... the others look pretty good. It's almost like I have too much positive camber, but I didn't think these cars have camber adjustments... Any Ideas?