Bmw m5 f10 disc

[Piston2022]

Hi all

Anyone has any suggestions on discs for m5 ?

My f10 has done 55k and rear disc thickness is 22.4 so worn out

Bmw stealership way too expensive as for read with pads it is £800 and front with pads £1400 so £2.2k

I understand rear minimum thickness needed is 22.6 mm and new it is 24mm

My disc thickness is 22.3 so Is it fair to say resurfacing won't help? If thickness is lower than manufacture spec then I guess disc ia not as strong as it is needed right?


Appreciate thoughts on pads and discs

[d_a_n1979]

TBH you'll get a lot of suggestions to stick with OEM, or who make the discs (could be ATE, TRW, Jurid, Textar, Galfer etc)

Have you looked on RealOEM for the part numbers and then seen what's available via Autodoc?

Are StopTech an option at all?

Speak to Cotswolds BMW too and see what they can quote you with the forum discounts etc

[mmm-five]

Are both front & rear worn, as you've quoted prices for both?

If it's just the rears, then do just the rears...and £800 isn't that much for 2 x 396mm steel discs and a set of pads on an F10 M5, and the lowest I've seen individual rear discs for is about £275 at Inchcape. So 2 of those (£550), plus pads (£150) is already £700.

RealOEM parts list
https://www.realoem.com/bmw/enUS/showparts?id=FV93...

If you want the best price on genuine parts...

Rear Left (34212284103) - about £290
https://store.inchcape.co.uk/products/bmw-genuine-...

Rear Right (34212284104) - about £290
https://store.inchcape.co.uk/products/bmw-genuine-...

Pads (34212284389) - about £145
https://store.inchcape.co.uk/products/bmw-genuine-...

Total about £725 (which is not a big saving, and is assuming the quoted BMW price doesn't include other miscellaneous parts or fitting).

If you are happy with OEM/OEQ parts then use the part numbers above to search.

Edited by mmm-five on Tuesday 25th June 10:29

[Piston2022]

yep both is worn I would say.

doing rear first as it is cheaper then front. You can't resurface them right?

Once it is below thickness of manufacture, what are the risks if you just change pads?

[mmm-five]

Piston2022 said:

yep both is worn I would say.

doing rear first as it is cheaper then front. You can't resurface them right?

Once it is below thickness of manufacture, what are the risks if you just change pads?

You can't resurface them if they're already below the minimum thickness, as resurfacing/skimming just takes metal away to make them smooth...and that's usually only when there's a run-out issue or build up of pad material making them rough/unbalanced.

Discs that are below minimum will not dissipate heat from braking as efficiently, and may be so weakened that they disc falls apart when you really need it.

Always replace pads when you replace discs, but you don't need to replace discs every time you replace pads, as pads will accommodate disc imperfections and you'll be bedding them in properly anyway.

BTW, the reason I was saying it's not a bad price, is because I was paying over £600 for much smaller 328mm e34 M5 rear brakes & pads in 2000.

Edited by mmm-five on Tuesday 25th June 11:04

[Piston2022]

So called up costworld and they charge £1.8k with forum discount and checked online and getting it done at dealer it is £1.8k so buying it from dealer and get them to put it on is cheaper than buying the part alone!

[mmm-five]

Of course both sets are worn...they'll only be 'unworn' if they've never been on the car.

What is the measurement on the fronts. Are they 50% worn and thus have thousands of miles in them, or are they 95% worn and should be replaced soon anyway?

Fronts start at 36mm, and have minimum thickness of 34.3mm (so 1.6mm of life).

[Piston2022]

Need to check front , rear is 22.3 but that is using varnier. Will test using micrometer. Pads at 4mm

[mmm-five]

Piston2022 said:

Need to check front , rear is 22.3 but that is using varnier. Will test using micrometer. Pads at 4mm

So you might still need front pads, but can save a fair chunk if you don't need front discs...yet.