Had Miss V ('99 XK8) out yesterday, driving her the way for which the car was designed - not crazy, just quickly. Went around a sharp corner at speed and there was an immediate loud repetitive squealing noise from the rear end. I pulled over to see if anything obvious was out of sorts and could not see anything. I went out to our 120k/hr (70 mph) highway and went quite a good deal more quickly than that for a couple of kilometers. The noise was still there - albeit a bit quieter. Back in town I took a corner the opposite direction from the corner which caused the noise and presto chango - the sound totally went away. Does anyone have any ideas. The car only makes the noise if I corner hard and stops if I undo what caused it.

Mike

 

Lift the rear tires clear of the ground and grasp each one at the top and bottom and then rock it back and forth. I would bet one of them would rock, indicating a bad wheel bearing. Squeals under pressure and quiets down when unloaded.

 

Mike,

I've moved your question from General Tech Help to XK8/XKR forum.

Graham

 

Also check the universal joints on the drive shafts.

 

+1 on Verns suggestions, though I found the wheel bearing noise to change or disappear as the bearing warmed up.

I hope it's something simple in the end
John

 

Me too. Frankly it only happens when I drive around a corner quickly, but these things do not heal like humans. They ONLY get worse, so I guess I will need to put it up on the hoist....

 

Have you lubed the axle joints?

 

I have the car scheduled for a spring tune up oil change and lube. I hope it will cover the issue. Good thought though too....

 

My son's xkr developed a horrible sounding squeal from the rear end some time ago. When I jacked the car up and had him run the driveline I found that it was nothing more than a dust seal that had come loose off the front of the differential. It was spinning on the driveshaft yoke and made an unbelievably loud squeal. I put some gasket sealant on it and stuck it back in and it's never come loose since.

 

thanks! I will look at that

 

My XK8 has developed a loud, I think rear end road noise. I would swear that I was driving with knobby, off-road winter truck tires. It's a constant hollow, humming like noise as the wheels turn, that gets louder as the car goes faster. If I didn't have almost new Pirelli tires (balanced & aligned), I'd swear it was the tires. They are all season plus - maybe that's the problem? But even if they were faulty, I wouldn't expect them to run this loud.

There is no uneven tire wear. With the car lifted, the rear wheels have absolutely no play at 3:00, 6:00 or 9:00. Both have slight movement at 12:00 which seems to be identical on both sides. There is some noise when I spin the wheel in neutral. Again, it seems to be the same on each side & I'm not sure it's the same noise?

Any suggestions as to what I should try next?

I'm thinking wheel bearings? But am a little suspicious since both sides seem to be the same.

I've never lubed the axle joints.

I'm unsure how to check the universal joints on the drive shaft?

 

In neutral, while turning a back wheel with the rear end lifted, I did notice that the other rear wheel turns in the opposite direction. I'm not sure if that means anything?

B-t-w, the noise that I described occurs in reverse too.

 

Peter,

Reverse wheel spin is normal on open differential like ours. If we were lucky enough to have limited slip differential they'd spin same way. Could the noise you hear while testing be the pads on the rotor?

I had similar noise in the rain with new brand of tires up front. Let's see what others think.

John

 

Thank you John! I actually removed the pads & rotor on one side, then spun the wheel by hand & it appeared to be the same. Because of the open differential, I found it hard to get the wheel spinning fast enough to see if the sound was similar to what I'm hearing while driving. While raised, maybe I should put it in drive & run the rear wheels fast enough to see if the road noise type sound is there?

 

Oh, & while driving, the noise is the same - regardless of braking, accelerating, etc. The brakes are pretty new & it's not really any kind of noise that I'd expect to hear from brakes. Something I didn't try was while driving, shift to neutral. I expect it would still be there, but I should check to be sure.

 

Peter, well its not the tires if it's not speed dependent. Let me think some more.

BTW- should have asked. when did this noise start? Same time as new tires?

Is it weather dependent? I've heard tires that got noisy in rain.
John

 

Thanks John! The noise is speed dependent, with regard to it getting louder as the speed increases.

Got tires this past summer. Didn't notice excessive noise until recently. Weather doesn't seem to matter.

I'm wondering how I troubleshoot to rule in our out:

=> wheel bearings?

=> axle joints needing lubrication?.

=> universal joints on the drive shaft?

 

Peter,

I can't imagine low lube would do this. IMO a large portion of X100 owners don't even know these obscure lube nipples even exist.

I've always found worn U joints to clunk since worn = play or space between the structures of the joint.

Bearings I've replaced 2 or 3 rear bearing on these cats. Sympoms:
Tend to be heat related (noise either when warm or cold)
Noise(s) more or less pronounced when weight shifts to one side or the other.
Noise is often speed dependent.
Noise is shriek, rattle, whine almost always metal on metal type sound.

These for me were at early stages of failure. One time, as one got worse, I would get STABILITY/TRAC Failure amber message in the display. Simultaneously ABS light would go off. Guess the speed sensor was wiggling in place throwing a code..

Peter do you have the same tires on front and back? If not swap them, see ifnoise moves. I don't imagine putting one full sized spare on would show you anything.

I wish I could help you zero in on the cause better. Hey, here's an idea. Launch a brand new thread with a title like: rear end noise need help ID'ing culprit. (Or whatever you like)

I suggest this because your issue is kind of buried here at the bottom of a similar issue from years ago. I bet way to many folks are just scanning past it, they don't even know you're here.

Summarize the key issues we've spoken about, it'll help you get fast answers.

New tires all4 wheels installed months before noise started.
Noise is speed dependent.
Estimate how much movement you feel at 12oclock.
What noise sounds like.
Not weather dependent.
New pads but not the noise source.
Braking, turning, weight shift (front to back) has no effect on noise.
Same noise in reverse.

Hope it helps man

John

 

Thank you so much John, I appreciate your effort. Good idea regarding a new thread, perhaps I'll include a video of the sound?

From what you've stated, I'm back to thinking it's got to be the tires. I looked it up & it seems that my rear tires are 6 months old. Since they're both 19", I'll try a front to back test.

Front: Pirelli P Zero All Season Plus 245/40R19 98 Y (Jan 2019)
Rear: Pirelli P Zero All Season Plus 255/40R19 100 Y (Jul 2019)

Thanks again!

 

Follow up - decided not to continue troubleshooting on my own. Mechanic stated (drivers side) rear wheel bearing. $900 repair & noise is now gone.