I was installing the summer wheels on the wife's 2013 MCS... and decided to take a look at the brake pad wear.
Both the rear left and right- inside pads show the same wear pattern as below. We've owned the car since new, it gets roughly 4000 miles a year and has never been autocross'd or HPDE.
Do Mini's have an issue with seized calipers? Should I consider a caliper rebuild kit, rebuilt caliper, or new caliper? Any thoughts? Thanks

 

Just re-grease the caliper pins. also check if the pads are flat.

 

MiniToBe, thanks for the input. Pads, rotors, pins and boots have been ordered. Fingers crossed that the piston isn't seized.

 

Yep those calipers seize of the pins are stuck.

 

So new theory here. Disassembled everything and the slide pins looked perfect, boots were intact and the slide pin grease wasn't contaminated. The inboard pads took a little bit of effort to release from the carrier. The pad clips looked like junk. My theory is this regarding the pad wear just in the center of the pad. The wife uses the parking brake as a parking brake... not as an emergency brake as I was taught with a manual. I'm wondering if that center pad wear is from the wife applying the parking brake everytime she leaves the car ( potentially with the brakes hot) ...and the thermal dissipation is leaving the center of the pad hot while the outer perimeter is cooling and contracting? Thoughts?

 

What does the outside of each rotor look like? Normal? I've never seen a steel rotor look like that.

How about a pic of the pads?

 

Agree 100% with you, I've never seen a steel rotor do this.
The outside of the rotor looks normal as does the wear on the pad.
The pick below is the inside of the rotor with the inboard and outboard pad shown.
This is why I believe that this type of wear is from my wife using the parking brake as a parking brake and not an emergency brake. My thinking is that when she parks the car and applies the parking brake, that the heat is trapped in the pad, caliper and rotor and that the outer edges of the pad, cool and contract faster than the center of the pad.

 

Your theory does not hold water and your wife is using the parking brake as it was intended. It is not just for emergency braking situations but to be used as an added safety measure when parking the car. I set that brake on every vehicle I drive, manual and automatic. Additional safety measures to take when parking a manual transmission vehicle are to place the tranny in 3rd or higher and turn your front wheels so that if the car was to roll that it would roll into the curb.

As for that uneven wear pattern, I cannot say. Never seen anything like it. Though, it appears the rotor may never have been completely machined or otherwise faulty from the day it was put on the car.

 

both sides of rear axle are like this?

editorial comment: I've NEVER seen a rotor THAT corroded and I've been doing my own brakes and for others for a while ..... like 20 years!

I set my e-brake every time I park ... manual or auto gear box .... that ain't the cause.

guessing but those don't look like OE pads to me ..... or OE rotors for that matter ....

 

Check this out, it looks like rusting on rotor during periods of non-use cause it to bulge
Bizarre brake wear on inside pad/rotor (pics) | Subaru Forester Owners Forum

 

Bottom Line: That car needs new rotors and pads as well as all necessary hardware. I would also check to significant corrosion on the caliper and piston. Brakes that are used on a regular basis, even as little as 4000 miles/year, should not look like that.

 

The caliper is not doing its job, if it was the disc’s would be clean.