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nobbyclark
17th January 2020, 01:32 PM
My JCW is now a smidge over 2 years old and has just clicked over 10k. At the recent service, the dealer recommended that the front discs should be replaced due to corrosion and wear. I find this incredible after such a short period of time and fairly low mileage. It is mostly driven 90 miles a week up and down the M90 (45 miles on Monday morning to park at Edinburgh airport and 45 miles back on Thursday night to Perth). Braking is minimal as there is not a lot of traffic at those times.
Certainly when it is parked for a while, I can see that the front discs are covered with brown surface rust. Is this usual? Also, if I do replace them, are the ventilated and grooved ones any better?
I don't remember my previous R53 suffering in the same way and it had a very similar driving profile between 2007 and 2016.

Track Ali
17th January 2020, 02:35 PM
Have you looked at your discs and had a feel at them yourself?

I'd suspect that the dealer is playing safe and/or looking for work. I've certainly been through my share of brake discs but the usage your describing shouldn't require replacement that soon. Surface rust will wear off and if you've worn grooves into the discs then some of the rust may still have been present when the dealer inspected it.

As for the dimpled and grooved discs, I'd say it's more of a cosmetic thing. I've certainly never noticed a tangible difference in terms of feel or performance. The only difference I'd say is that you can hear the ventilated discs when you brake as the pads passing over the dimples generates a faint sound of rushing wind. It's not loud though so I wouldn't let it put you off if you fancy going for them.

nobbyclark
17th January 2020, 02:53 PM
Yes, I have taken a look and if left for a few days, they certainly look a little brown. But as you say, after a few applications, the rust wears off apart from what is in some of the grooves. I do like the look of the ventilated discs but not sure if (a) they are any better (had them on the R53 as well) or (b) worth the £350+ outlay before fitting costs are added.
Just wondered if anyone else had similar issues or whether it was the damp microclimate up here in Perth.

badwolf340
17th January 2020, 07:40 PM
Brake discs nowadays seem to be more susceptible to the Elements and are almost a serviceable item .

Kettlepot
18th January 2020, 06:14 PM
I’ve always found that the rears corrode more than the fronts. As the fronts do most of the work, unless the sliders are sticking and one side of the disc isn’t wearing properly [emoji2371]

nobbyclark
21st January 2020, 10:13 AM
That certainly used to be the case on my R53, where the rears were often rusty looking. However, the F56 is the opposite. Will ask them to look at the alignment of the callipers as there does seem to be a slight knocking when braking, which stops after a few applications.

nobbyclark
13th July 2020, 11:22 AM
Finally got the discs changed last week as the knocking was really starting to grate (even though I've only done 300 miles since March 1st). Both front discs were really badly corroded and scored. Pads were also very worn. So far, braking feels even better than when I first got the car new in October 2017.

badwolf340
13th July 2020, 04:05 PM
Brakes are a pain nowadays,seem to be a service item now .

Harmchar
24th July 2020, 11:44 PM
I've fitted the Brembo black discs on a previous Audi and they lasted less than a month before the coating is worn off. Total waste of time. The outside edge of the vented n grooved discs stayed black slightly longer I suppose, but in my opinion was not worth the extra spend.

nobbyclark
27th July 2020, 10:08 AM
I went with the ordinary discs in the end. Along with the new pads, the brakes now actually feel like how I expected them to 3 years ago when I first bought the car.

badwolf340
27th July 2020, 07:11 PM
I went with the ordinary discs in the end. Along with the new pads, the brakes now actually feel like how I expected them to 3 years ago when I first bought the car.
Good to hear that you are pleased with the outcome