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Help diagnosing sportwagen rear disk brake issue

Guys, I need help determining an issue with a rear disk brake.

Pulled the wheel because I was hearing whisssh , whissh sound there, twice per rotation. I suspected a brake pad dragging twice per rotation (rotor warped?).

But when I looked at the rotor, I saw that the outboard pad was only touching the rotor in two places.

And the inboard side of the rotor has strange marrings on the surface that almost look like it’s been welded and ground. These marrings on the surface are higher friction when I run my finger over them, so they could possibly be the source of the noise.

Oh. And strangely, the noise doesn’t go away when braking.

Any help diagnosing would be appreciated. I’ve attached pictures, although I don’t know how useful they’ll be.

Welded looking area is a tiny bit clockwise form 12 oclock.

Thats typical of a worned rotor.Replace both with new ones along with the pads.You also need to lubricate the slider pins with brake grease.Who is doing the brake job?

Only 15k on the pads and rotors, and I drive like your Grandma.

Rotor is still at initial thickness of 10mm. Pads have plenty left too, although outboard one is wearing slightly faster at the bottom.


I know the default answer for any brake problem like this is new pads and rotors, but is there anything else it could be?

Forgot to say:. I’m doing the brake job.

Bent axle ?

Hope not!. The wife would be in trouble :slight_smile:

I’m going to try and sand the rotor and see is it’s a simple as some rust.

Does this have a small drum brake that fits inside the hat section of the rotor for the parking brake? If it does, you are probably hearing the drum brake shoe rub the rather large amount of rust on the INside of that hat section.

I think we’re looking at the inside, pretty rusty if there’s a drum parking brake.

@Mustangman @texases

No drum brake. Parking brake is actuating the caliper piston.

I guess the rotor is probably just warped. Should I try to get away with just replacing that rotor? It’s a PITA to replace everything else at the same time, since it only has 15K on it.