For a couple of months now, at speeds over 40 mph, I've had a brake applied rumble and vibration coming from the Rt. rear wheel area. I have '98 XK8 with 91,000miles. Checking suggestions in previous threads I focused on a warped rotor. I had less then 20,000 miles on the after market drilled rotors with ceramic pads but replaced them anyway. Had the new rotors, OEM type, trued and found they were perfecly flat. Made sure the Tech torqued the lug nuts. After installation, the noise and vibration, were still there with no change. A shake of all joints, both sides, with a bar couldn't find anything loose. Any other suggestions before I go see dealer? Since it's not brakes it may be pothole caused damage. On some roads they're shoulder to shoulder. New Jersey grows them like the mid-West grows wheat. Jack

 

well, vibration would definitely be felt if the wheel is bent...but a noise too? Hmmm...if you didn't see a previous thread I started awhile back (months) I had a noise and some vibration, but it was more in the lower speeds however. The lower bushing was all kinda spent. Only way i could diagnose this (and it took many different people before motorman up north of me showed me how to do it) was by lifting the rear, putting the rear on jack stands, then putting the jack under the rear wheel...getting it just where the weight of the wheel was being supported by the jack...little or no suspension movement, then hit the bottom of the shock with your fist...it made a banging noise. When its fully extended (w/o the jack under the wheel) the shock was pulled to its full length, and a force exerted on the lower bush to the bolt, no noise could be heard when hitting it then.

couldn't hurt to check it that way.

Check your bearings to...look for play in the wheel in any direction.

 

Thanks H20boy. Did you get the vibration all the time or just when applying the brakes like me. The noise I hear is the vibration of the body. Kind of like going over the highway shoulder rumble strips but not as loud. Can the lower shock bushing or lower control arm bushings cause noise only when brakes applied? Jack

 

unfortunately, I did not get the noise specifically while braking. do you get the noise while going over bumps, or is it on any surface at any speed? Besides my RR shock, the rear suspension components have been very reliable, not requiring any type of maintenance...arm bushings, sway bar rubber, etc.

In addition to the noise at that low speed, I did get a slight vibration at high speeds as it was transferred to the driver. I could tell, because after the shock was replaced, nothing else being done, all of a sudden I didn't have as much high speed vibrations. A couple months later, I repaired my front wheel (very smallish bent rim) and elimiated all vibrations.


Brutal recommended cleaning all the corrosion on the hub also, around the lug studs so the face of the inner wheel matches up evenly on the hub.

Do you have any play in the wheel in any direction?

 

H20boy, The tech and I tried shaking everything. Couldn't find anything loose. I can run the car from 0 to 70 and not have any vibration or noise but the second I step on the brake to slow down it starts. No noise or vibration going over bumps or stopping while going slow. I know what you mean about bent wheel vibration I just had 2 wheels on my X-type repaired. Ever hear of a problem with the caliper causing these kind of problems. I can't even guess how to check it out at high speed short of strapping the tech to the rear fender. I don't think he would appreciate that too much. Jack

 

You may need to take Brutal's other recommendation and actually have the rotor runout measured with a dial indicator.

 

Well, you could always throw a salvage caliper and caliper bracket at the car...to rule that out. Other than that, and the hub...not sure what to tell ya.

 

Well I'm at the dealer. Took the shop forman for a ride so the noise and vibration would be duplicated. Had to heavy brake from highway speed to get it started then I would get the problem every time I braked over 40mph. We're going to try a "Jaguar" rotor and pad on the side the sound is coming from. If that doesn't solve he problem....Oh well Jack

 

Crossing my fingers! They've got the parts at least to try.

 

Forman just came back after installing Jag brake parts. No change!! Going to put old parts back. Now he's looking at motor mounts. Right side is definately bad. Engine raises way up while power braking. Took one of the techs out for a ride to get another opinion. $$$$$$$$ Jack

 

The second set of eyes and ears worked. A new set of.... FRONT.... Jag brakes and the noise went away. Some how the noise was resonating to the back. Have to pay for the Jaguar front brake job$$$ but not for any of the diagnostic time, 4 hours. Guess I'll have to go back to cleaning the brake off the wheels again. Didn't have to do any of that with the aftermarket parts. Will have to think a while about the motor mounts. Jack

 

what pads and rotors were you using? I'd still redo the pads...maybe next year with some ceramics.

 

h20boy, I believe I got the bad rotor from Brakeworld might be Centrix brand. They were drilled and I had Ceramic pads. Maybe too much heat for the thinner rotors.That wheel also had 2 lug nuts that somebody didn't put the socket all the way on and damaged the thin covers. Don't know if this would affect the amount of torque applied to the nut. Couldn't get a 22mm socket on. Had to use a 23mm to remove those 2 nuts. The 2 nuts were next to each other. I hate those "freekin'" guns. I will go back to Ceramic pads with the "Jag" rotors ASAP. Not having all that black crap messing up the wheels makes cleaning the car so much easier. Jack

 

I've got 15 old OEM lug nuts if you want a few spares. I replaced mine awhile back. Or, you could pay $25 a piece at the dealer.

My tire shop gave me a little grief when I asked them to not use the air tools to remove and install my lug nuts. But when I spend $500 for two tires installed at a time, they didn't refuse. I know it takes an extra 5 minutes a wheel to use a torque wrench and your hands, but I don't want to ding the SS nuts that were made for me.

 

Thanks h20boy but I got 5 lug nuts from wherejagsgotodie.com. Jack

 

Very glad to hear this chapter has closed, and you got those subject lug nuts swapped out. You have a whole new appreciation for the car when theres no vibration, doesn't pull to one side or the other, there arent any noises, and you can just E N J O Y the driving experience...and focus on the vehicles aesthetics. Now, give the cat a good detail for all the invasive procedures you just put it thru.

 

Amen!