I drove 1300km during the weekend, going from Liechtenstein to Monaco and back. On the way home my wife commented on a noise, which sounds like "road noise", as the tire treads touching the asphalt. I had a bit of this from when I bought the car already, but I simply thought it was road noise from the P-Zero's, which I've heard are noisy.

Now the noise has gotten much, much worse however, and it sounds like it might be coming from the rear, although it is hard to determine with this kind of droning sound. The noise gets louder with speed, and its pitch follows wheel rotation.

So I guess I'm looking at new bearings as well. Since I also need new discs and pads all around, perhaps I should do a complete 4x bearing+disc+pad job.

I was thinking about handing the discs+pads job myself, since it looks pretty easy, but I won't do the bearings. Looks like you need some special tools to handle the job. Besides, when doing the bearings, putting some new rotors and pads in I suppose would add about 5min work per wheel...

What could I expect to pay for this?

[youtube]IcGtv3jmnIM[/youtube]

 

It could also be the suspension bushes.

 

I drove 1300km during the weekend, going from Liechtenstein to Monaco and back.

I've got you beat!!

I drove 12 miles to the grocery store and back...twice, (forgot the Cheerios first time).

Honestly, that sounds like a dream trip.

I just replaced my pass side bearing in front and I am usually pretty good at hearing those go, but never heard a thing on mine.

Typically if you load the side of the car w/the bad bearing at speed in a turn the noise is reduced somewhat, but..again, I did not hear mine and it was so far gone the wheel cambered out a good 2-3 inches when we got it on the rack

 

The noise actually seems to be pretty much constant regardless of turning. Perhaps I should do the old 6-12 o'clock wiggle on the wheel and check for any play.

 

The list of possibilities grows - check the diff.

Nice drive to Monaco and back. Beat you for distance the weekend before. Gibraltar to Durham (1780 miles).

Graham

 

azeteg, how many miles on the car?

EZDriver 2000 XK8

 

96k miles.

 

Did the 12-6 wiggle, and have about 5mm play (top and bottom of wheel) on both rear wheels. I have a hard time suspecting a bearing issue, this play is the same on both sides, and is probably from some worn bushing.

Also did some "spirited" driving wiht turning, but the noise remains constant through both left and right turns.

The quest goes on...

 

Sounds more like a rear end to me. Better have it checked right away.

 

Could be u-joint failure

 

What does a rear end encompass?

Unfortunately I cannot check it out for a while, I just woke up from an 8-hour long spinal surgery, and am unable to drive for 6 weeks

Reading jag forums from the hospital bed right now, all drugged up.

 

I still think it's likely to be the diff as in Post #5.

Here's a graphic of the rear end:

JTIS - 2002 Rear Drive Axle and Differential.pdf

Note also the UJ's on the drive shafts.

Best wishes for a speedy recovery from the surgery.

Graham

 

Thanks. Is there some test I can do for the diff, or do I need to get the car off the ground, put in drive, then walk around and listen?

Thanks for the wishes. I'll be hospitalized for 10 days. I have already been up and taken 3 steps though, even though I almost fainted. Stuffing myself with good Swiss chocolate should help for a swift recovery

 

You can check the drive shafts with the vehicle off the ground. The UJ's should be greased at scheduled service but are often ignored. There's quite a lot of rubber bushes involved in the rear suspension isolating vibration. Any of these may be worn and transmitting vibration.

First examination with the diff itself would be oil level and then whether there's any metallic particles in the oil indicating excessive wear.

If the oil check out OK, then input and output shafts are next on the list.

The following link is to the JTIS section covering removal an installation of the diff:

Free Cloud Storage - MediaFire

Much more information than you need but pages 4 and 5 illustrate the tie rod and stabilisers.


Graham

 

Hey Azeteg,
If you ease off the throttle does it reduce? Does it change when loading left to right? If I were to make a stab at it based on your video I would suspect a pinion shaft bearing, its the bearing where the prop shaft enters the diff. Almost 100% its not u joints, they generally make more vibration than noise. Incidentally there is a surprising amount of end float on the rear wheel bearings so the 12-6 test can be a bit misleading, if its excessive its most likely the lower pivot bushing. The only other area I would suspect would be the output shaft bearings in the diff, its a pretty simple fix. Hope this helps, good luck!

 

The noise stays constant even if I ease off on the throttle, brake or turn sharply right or left. Pinion shaft bearing sounds possible for sure! I'll look around a bit in JTIS.

I also don't expect the wheel bearings anymore, the 5mm top to bottom wheel play isn't much at all, I suppose that could be due to a shock bushing...

 

Had the back left wheel bearing fail in my 2004 XKR at 65k Km , was so worn it had created a lip on the hub and we had to replace the hub as well, luckily got a good second hand one. The noise was no where near as bad as it sounds in your recording so I would be getting the rear end checked out pronto if I was you.

 

I'll have the rear end checked ASAP. Still in hospital though, plus a 6 week ban on driving, due to the surgery. The cat will stay in our garage meanwhile, and the wife will use the BMW.

 

I did find some other videos on Youtube regarding pinion bearing noise, and they sound EXACTLY like the noise I'm having.

What should I expect to pay, approximately, to have the pinion bearings replaced?

 

In my younger days working in a dealership I observed cars on jacks driving the rear wheels with the wheels off the ground. I was amazed at the noise that came from the differential. It would sing like crazy. I was told by the old experience guys that it was normal with no load on the unit. I also had a 240z that would always sing a little in the differential. In that car you could hear it more than other cars since the differential was mounted on the body directly rather than through springs like our cars. That car went 150K miles with no problem. My point is you might be getting fooled by running the car jacked with no load. There might be absolutely nothing wrong with it.