Brake pulsation
 

Well - I've finally given up on the drilled / slotted rotors on my 2010 V8 SC. Several years ago I replaced all the rotors with R1 Concepts drilled/slotted and put on EBC RedStuff pads. In less than a year and a few thousand miles I got bad pulsation on braking at highway speeds
R1 Concepts replaced the rotors under warranty (no questions asked - very helpful) and I installed them meticulously myself, cleaning every seating surface, lubricating etc. But 18 months later the pulsation was back. Looks like uneven wear and deposits on the rotors

I've had the dealer do a thorough investigation and they are sure hubs, calipers, wheel and suspension components and everything else is fine. Also had a brake and tyre specialist check it out with same conclusion

So - after living with it for a while I have sadly gone back to Jag OEM rotors and the Porterfield R4-S pads. Only a few hundred miles so not much to say yet. Think the drilled / slotted look was nicer. But most important is to see whether they hold up. I'll report back!

I use sonax wheel cleaner. Is it possible that wheel cleaners could attack the surface coating of the rotor or the pads and cause that issue?

Unlikely to be the Sonax with the amount of people using it & no reports of this. I had drilled & slotted discs on my STR (Brembo setup) when I first got it; they started pulsing not long after. Changed back to OE discs & haven't had a problem in six years odd (touch wood).
EDIT - they did look good though.

I have that setup with brembo pads, it's been around 2 years, and still perfect, although i haven't really done much driving just around 1000 miles.

Sounds like the classic "brake pad deposition" problem, I think you said it yourself with "....Looks like uneven wear and deposits on the rotors".
Lots of discussion about this on this forum and especially over on the Pommy Jag forum where they call it "brake judder", but the bottom line is you MUST bed new pads and rotors in properly to prevent pad material deposition on the rotors. Several sites/pages on the Web where they explain how to do it, sorry no link(s)!
I bought Hart brand drilled and slotted rotors for my old 2010 XFR some seven years ago then swapped them over to my F-Type and I have NEVER had any brake pulsation or judder, which I put down to religiously bedding the pads and rotors in each time I changed them. From all my research I am fairly sure that almost all of the Jag slotted and drilled rotors from Hart, R1 Concepts and so on are the exact same rotors made in the same Chinese factories.
Bed those pads and rotors in!

Agree with ozxfr, when I fitted the brembo ceramic pads i made some hard runs and hard braking, after bedding in it's really noticeable, i also had to change my master cylinder as it was spongy and juddering.

Yep all these rotors are Chinese made.

The other problem might be a bent hub, i had that in a Chrysler what ever rotors i used after some time it's started juddering.

Thanks. Yes - I wondered about bent hub and had them checked a few times and all running true

Hi Oz - i did the bedding in as recommended by R1 and EBC. But it didn't seem to help for me. Sounds like exactly the same issue you had Carlos. I found it took around 4000 miles for the issue to present itself so you may still have it again. Apparently it takes that long to get the uneven wear to be noticeable

I talked to a specialist performance shop up here in NE USA and they advise against drilled / slotted in the climate up here. Not entirely sure why, but he said he sees this a lot on performance cars that have them fitted as a mod

So - I guess I'll see in 6-9 months how it's holding up!

When I bought my car it had the OEM rotors, and the juddering and spongyness was already there, my rotors where warped.
Once i changed the rotos (drilled/slotted) and master cylinder it's been, perfect, it fixed the problem immediately, so far it's been great hope it holds up

About the bent hub i had it in another car i took it to many shops nobody did notice it, it took a long time to spot, i removed the wheel spun by hand and held a piece of wood about 2 mm from the hub, only then did i notice a very slight wobble, enough to cause all the issues i changed the hub and problem solved for good.

Salt and then rust can take hold in the drilled areas as they aren't wiped off of the face like flat rotors would be and then begin weakening the rotor.

This is how I corrected the same brake problem on my XF
JagRepair.com - Jaguar Repair Information Resource

Gus
JagRepair.com - Jaguar Repair Information Resource

Thanks. It's an interesting theory. But I use the parking brake (unlike a lot of people in the US it would seem), which worked fine. And I don't really understand how that adjustment would matter when braking as it's still a hydraulic brake system when using the pedals. I'd love to have tested the idea.

But, I've already changed all the rotors for Jag OEM ones, and the Porterfield R4-S pads. And it now drives perfectly. So it seems the drilled / slotted rotors didn't hold up well.

All I can say it worked for me and I did not replace any parts on the brake system.

Yes - if anyone else has issues it would be great for them to test it and see if it helps