As a matter of fact, nearly all front and rear suspension components were recently replaced under warranty. Everything else appears tight and in spec. By the way, I have no vibration.

 

The company I bought them from supposedly checked this. They do have a lifetime warranty. I might have them re-checked tomorrow.

I am perplexed how 4 brand new wheels go from being fine with the Michelins to being out of round with the Pirellis :/

 

Check to see if one of the wheel has significantly more brake dust which will be obvious if you are using semi-metallic pads. Lift the car and turn each wheel by hand and you may find one that may be dragging. Take off each tire and remove caliper and pads and examine the brake rotor for anything unusual. Make sure the pins on the rear pads line up with the notches in the piston of the rear calipers or they will be cocked and not contact the rotor in the same plane. If you did not use the proper retraction tool to rotate the piston back into the rear caliper you may have damaged the caliper, which will be obvious because it will not release properly and drag. Bleed the system at least twice and follow the special procedure for bleeding rear calipers with electric integral parking brake, then follow the electric braking brake calibration procedure. If there is still no relief take the rotors to a machine shop and have them checked for trueness. I have never had a bad rotor out of the box, but it maybe possible.

When you rule out the brakes then move on to the tires. There maybe a bad belt in one of the tires. Take the spare and rotate it into each position and test drive. Start simple and move to the most complicated.

 

I have Brembo brakes, rears were done with no issue a couple of months ago and the shake in the steering would indicate a front end issue. IF it is the brakes, it would be either the pads or rotors but wouldn't I feel something in the pedal?

Jag said all four tires had flat spots. I am tempted to bring them back tomorrow and just spend the extra for the Michelins.

 

This.

 

?

 

I would start here. But that's just me.

 

Y'know last year I had vibration and shimmying when braking from speed, and thought it must be the front discs. However it disappeared when I had the rears replaced due to being on the wear limit. Strange !!

 

I started by hoping my experience would assist the original thread starter, now I feel like I am hijacking here...sorry!

I am still having vibration at 60MPH+ Jag dealer roadforce balanced the tires, the vibration lessened but they are suggesting the OE Pirelli P Zero tires are not appropriate for my application and I should go back to my Michelins. UGH!!!!

Are Pirelli tires that bad?

 

Pirellii's have been bad for me in the past.

What I meant with the "this" was that I was agreeing with you (that you should do what you were tempted to do) and that you should get the Michelins.

 

You do occasionally get a bad tire even from a good manufacturer. Are these pirellis new? If so you can always try to return them. If they have more than say 15k mi and are more than a couple years old, it is possible that they are getting hard in spots - this is what drove me from kumhos. When the tire hardens unevenly, it wont balance at high speeds and you need to get rid of it. Not saying this is your problem but I've had this problem before.

I dont know if pirellis are prone to this or not. I stick with Michelin, Bridgestone, and Continental. I am fortunate to know exactly what tires I want and why, and these three offer what I want. So, unfortunately I can't say anything about Pirelli. They are stock on Jaguars though, so can they be that bad?

We have discussed the by-far two most likely causes of your problem - wheel balance and warped rotors. Its possible you have a slightly bent rim that prevents your tire from balancing. Also, if your tire guy cant do a road force balance, he could have the wheel balanced at low speed but out of balance at high speed. It absolutely can be difficult to find a good tire technician; I would check around if I were you. The brake thing is much easier to check.

 

After spending some time doing a lot of hard braking it appears THAT vibration is gone.

The issue with the rims/tires persists.

I thought I had mentioned it, but the tires and Jaguar rims are brand new. The Jag dealer roadforce balanced them twice and determined the tires are out of round with flat spots and the rims were out of round but within factory spec.

The vibration from about 60MPH persists.

The car calls for 96Y rated tires, the P Zero Nero is 98W but also available in a 102H which is OE on the new XJ. Could that have anything to do with it? Oh and for some reason the 98W is 3 pounds heavier than the 102H and 96Y Michelins, FWIW...

 

That is your problem right there. I would have demanded replacement tires on the spot, before leaving the shop. Out of round cant be balanced away, and it depends on the driver whether you notice it/it bothers you. Sounds like the rims aren't acceptable, either - within spec or not, if they are too off that you feel a vibration, since you are buying them new, just return them.

It sounds like your only choice is to replace those tires - or at least those that are out of round. Rims too, depending on the severity.

You always want to use the same load rating or higher that came with your car. Other than that it doesnt make too much difference; it wouldnt affect balancing issues.

Last thing - with tires and rims, lighter is better. You dont want a rim that is so light that it is fragile though - you can have light, cheap, and strong - but you can pick only two =) For a given price and strength, go with the lightest rim you can find, speaking generally.

 

Getting them replaced under warranty is not the problem. My hesitation is what will solve the problem, I hate going through the trouble of replacing the tires, for example, to find the issue hasn't been solved or getting another set of jaguar rims to find they too have in spec deformity. The dealer of course said I should start with the tires I know, the Michelins at double the price of the Pirellis, not that I can't afford it but I guess I'm getting a bit frugal when I can buy something tire rack rated higher for half the price.

Of course tire people will say you should never go down in speed rating, but as I mentioned before the same tire with higher load rating but lower speed rating is 3 pounds lighter and is now the OE tire for the new XJ which now gives me a 3rd option to chose from, if that can be considered an option. I don't drive 140mph anymore, so speed rating means nothing to me unless it has a big impact on handling.

And thus I am left in a quandary.

 

Get a good mechanic to check the runout on the brake discs you installed. The discs are part of the locating mechanism for your wheels. If you have runout, you will have vibration.

 

Try the Michelins. Trust me. But I would also get the dealer to provide rims that are better than "in spec." I.e., can you get rims that are not close to the limit of the spec? Splitting hairs, but that's how these things go.

Another thing to think about. if for example you have 19 or 20 in rims, going to an 18 in rim will make a big difference.