We've had rotors and pads replaced under warranty already once (last year) due to a strange corrosion which developed on the rotors.
Yesterday noticed a grinding noise while driving the wife's CM (same as before). Brakes felt like they had lost initial bite and 20-30% of stopping power (same as before). When I got home I looked at the rotors and they looked like this (pics below). Same issue as before. This was after driving the car for 30 min or so (highway/city etc). We're going to take it in again this week... they must be using some really cheap rotors in these to corrode like that...

 

Those rotors definitely look funky. Could that be from the road salts?

 

I have no idea. Maybe... they are exposed to the exact same conditions as any other around here...
We have not had any salt or chemical on the roads since March though - regardless, that shouldn't be happening either day.

 

Looks to me like you are too light on the brakes, and not getting good contact with the rotor. Go out and perform some hard stops and see what they look like.

 

The vehicle is driven as designed. My wife mostly drives it when carting around our 17 month old. Stops at lights and stop signs just like any other car. She shouldn't have to stand up on the brakes to keep them operating normally LOL. This has nothing to do with driving style, nor should it (obviously). These are a standard brakes and should wear normally for standard usage.

With that said - I did try exactly what you said to "scrub" the rotors which resulted in no improvement.

The car goes in today. I'll update with results.

 

If that's the case, do they still operate as expected, or is there a lack of braking performance? If they work and function as expected, but they look "odd", who cares?

 

The cheap Centric Rotors I put on our 11 Countryman 40K miles ago look brand new compared to those rotors. Looks like MINI went and sourced the cheapest crap they could find or got stuck with a batch of defective ones.

OP's original post states the issues.

 

Thanks - no they don't. Stopping "power" is probably down 40% if not more. It's as if there is a piece of paper between the pads and rotors.

Thanks - and yes totally agree. I've bought lots of aftermarket "OEM" replacement pads and rotors for many vehicles. I'm very mechanically inclined too - I own a B8 Audi S4 which I've done brake work on myself and a Honda S2000 which I've done a lot of work on myself... I've never seen brakes corrode like this before...

I'm actually very surprised no one has responses with similar issues...
The car actually goes in tomorrow - so I'll update as I get information on how they want to handle this (seems to me like crap quality products).

 

With that much pitting on the rotors you're not getting 100% contact with your pads. That would explain the loss of braking. Rotors will "rust" right after it rains, until you drive them again and the pads should clean them. If it was my family, I would replace rotors/pads with aftermarket. They don't have to be expensive. You can source them online (slotted/drilled with ceramic pads) for less than $250 (all four) on an R53. What I did (R1 Concepts) and they work just fine for daily driving. Here's an example: https://www.ebay.com/itm/For-2014-20...8AAOSw0~pcEevz

 

Yes - my thoughts though are that this is a caliper issue if pad contact is not being made.

 

The dealership basically BS'd me - said it's "normal" but yet they are replacing the pads and resurfacing the rotors. I pushed for new rotors but they said warranty guidelines won't allow it... yet they replaced them last time.
It's just a case of cheap quality parts IMO.

 

Was one pad significantly more worn than the other (same caliper).

I thought it was anomylous when it happened to my MY17 Clubman S ALL4 (Manual), but I just looked at my wife's car which is making horrible noise under braking (hers is at around 35k miles on the clock).. Same exact exact problem with her MY18 Countryman S ALL (Manual).

It is the passenger side inner pad. This occurred at between 30 to 35k miles on both cars. My Clubman is at around 64k now, and while I have not checked the brakes, I am guessing the prognoses is not good.

Picture, note the inner pad is already to the backing plate with the metal wear tab grinding. I never did take the pads to Mini when I replaced mine last year, now I am thinking I should have, this has to be a manufacturer issue, but I could not find any recalls or notices. Other than that one pad, all the other pads on the car have plenty of wear left in them.


Uneven pad wear