Andrewck

Changed my front brake pads a month ago and just changed out my front rotors today. Both instalations went smoothly. Took the car for a spin and there was a scraping noise coming from the rotors while driving at a lower speeds (I'm sure it was there at higher speeds, but couldn't hear due to wind / engine noise). Scraping noise apparent during turning the wheels as well. Got back after the drive and there's a strange wear mark on the rotors after just 5 mines.

Is this normal for new rotors? burrs that come off, normal during bedding in process? Haven't done rotors before, so all new territory for me. Thanks all!

Andrew

dgjks6

I have done lots of breaks. Not normal.

Pull the pads and clean everything

Can you feel a ridge or anything?

I have no idea what could have caused it

napoleon1981

Not trying to be an ***, but are you sure you installed the pads in the correct direction? It looks like metal to metal contact to me.

DTMiller

Yeah,that's super weird looking. Disassemble and check everything.

Slakker

I may have done this before and that's the exact symptom. Lol. Just turn the pad around and it will smooth the rotor back out for you.

808Bill

Was it 4:20 when you made the mistake?

silentsod

Provided that you have the pads installed the right way (new rotors with old pads will wear unevenly across the rotor face at first) check to see that you have correct clearance with the backing plates to the rotor. I had heavily dished rotors and put new rotors on only to find out that my backing plates are warped and brushing the rotors.

Gbug

Living in CO, this seems like a relevant question to me

Vancouver996

Changing out the pads first would have imprinted the old rotor wear pattern on them , especially with very worn rotors , then putting new rotors on the pad faces won't match up. You should always use new pads on new rotors , this gives a flush to flush surface . You can create groves in the new rotors doing what you did , especially with performance compound pads . Your pads are damaging your new rotors .
You should take the pads off and buy new ones . Expensive lesson
To continue driving the car like this and every time you use the brakes you are machining the old lands and grooves wear pattern of your old rotors into your new ones . This will result in having to replace them much much sooner . I wouldn't drive the car until the pads are swapped out .

Ahsai

^+1

What kind of rotors are these and what are those pins inside some of the vent holes?

sweet victory

It almost looks like the machining operation didn't finish those holes? They're not chamfered like the rest of the holes.

Vancouver996

It looks like where the cross drilled holes lined up with the vanes between the rotor sides . Could also be balancing slugs

808Bill

Breaker- braker, come back!
Should be Braker-Breaker...

Ahsai

Yeah. They look like counter weights of some harmonic balancers

dkraige

You're kidding, right? This is nothing to worry about and is pretty common with any new pad/rotor combination, whether one side of the interface is used or not. Even with brand new parts they will not line up exactly. The mating surfaces will continue to adopt each other's shape until they are matched over the next few miles and this will be a thing of the past. This will not appreciably affect the life of the pads or the rotors. It hasn't even worn through the cross-hatch pattern on the rotor yet.

The only question here is what is the scraping noise. Backing plates? Rocks or other debris stuck in the caliper? Caliper not retracting and dragging the pads on the rotor? I suspect the noise is a totally separate issue from this preliminary wear pattern.