Hey guys,

I have a irritating problem. My steering wheel is shaking while braking *when my brakes are warm*.

I've just got back from a tour to the Swiss and Italian alps (Stelvio pass included) and also took a lap on the Nürburgring Nordschleife on my way back. When going downhill in the alps, when braking more than just occasionally on the autobahn and after like 3 turns on the Nordschleife, the shaking starts. If I let the brakes cool down, it stops.

The thing is: I knew I had this problem, so before leaving on the trip I changed all four brake pads and all four brake discs to brand new genuine parts at an authorized Jaguar workshop in order to get rid of the problem as I figured it must be a warped disc or something. As soon as I reached the autobahn 1 day of driving later, I realized the problem was still there (!).

Videos of it happening here: https://we.tl/tRELRvehfW

So what on earth can this be? It can't be the discs as they are brand new, and the problem persisted after changing both pads and discs. Grateful for any help or guidance!

Cheers,

Jonas

 

How's front tire wear? Cupping or uneven?

 

Two thoughts:
Check out the runout on your front wheels (might be bent)
Front tire cords may be delaminating (more likely given the problem description).

 

you say it has new discs
I have seen this happen when new discs are badly fitted
and as others have said check tyres and wheels

 

Try wheel balancing!

 

I forgot to add that to the original post, but I also fitted brand new Michelin Pilot Sport 4S a month ago, so it shouldn't be the tires.

What does "runout" mean in the context you refer to? Sorry for not understanding, English is not my native language.

Thanks for the tips anyhow.

/Jonas

 

I bought new tires a month ago, so my wheels should be balanced already. Also then it wouldn't make a difference if the brakes were cold or warm, would it?

Thanks for the tip though!

 

Tires are relatively new, can't really see much wear at all so I'd say it's even?

 

Balance would not be affected with hot or cold brakes, at least I don't think so!

 

It could be a sticking front brake caliper slide pin.
Doesn't stick when the brakes are cold as it sits a bit loose in the bore/sleeve, but when the brakes get hot the slide pin expands just a tiny bit and now sticks.
Try removing, cleaning and lightly greasing (with high-temp ceramic based brake grease) the slide pins and the sleeves they fit in, not a big job.

 

Runout is just the variation in surface position of the wheel at the beads as you measure around the circumference of the wheel.. It's simply a way of determining if the wheel is bent. Not a likely cause in your case because it only occurs when things warm up..

 

Hmm sounds like a plausible cause to me. Thanks for the tip, will check it out!

 

Did this work? I just posted the same issue with my 2011 XF. Exactly the same thing is happening that you described. Changed everything and it still happpens. Did you try lubricating the brake caliper slide pins? Thanks!

 

I contacted Jaguar and got brake discs and pads changed again as a warranty claim on the previous job. I have no idea if they did anything else at the same time, but at least the problem's gone. Maybe they lubricated the brake caliber pins as well, I don't really know. I'll send them an e-mail and ask.

 

Thank you! I look forward to hear me what the dealer says. Mike