Groove in center of Rotor

[BreckAConner]

Good Morning,

I had a question about my rotor. I had bought the economy Brembo rotors and pads over a year ago, because I was tired of buying the cheap crap that would warp. I noticed last night I have a groove in the center of my rotor and I was wondering what causes that wear? Brake pads/Rotors/Calipers are good. No shuttering when braking or noise. I wasn't sure what was causing the issue so I read up a little and found different answers and would like the forums opinion on what could be causing the groove.

I read it was hooking, and it's normal wear? That is could be something was wedged? Bad wheel bearing? Stud in brake pad, (not worn tho) so I'm confused to what could cause the groove?

== lip of rotor
|||
||| groove
|||
==
==-- hub
==
|||
||| groove
|||
==

[Raf99]

If the caliper is sticking it will do this. Jack the car up and spin that tire, compare to the rest. I'm assuming the groove is where the pads are?

Also ...
- is this the front or the rear?
- is the groove on both sides of the rotor? (if not, which side)
- have the caliper pins been properly lubricated?

[cp[mike]]

i would say either some debris got wedged in there and became embedded in the pad. That, or the actual pad material itself was poorly mixed and it has a "hard spot". Either way, I'd probably replace the pads.

[oni_cb7]

You stated that the pads were a year old and that they don't look worn. What exactly do you mean? Is the thickness of the pad material less than the backing plate?

[F22Chris]

If you have a sharp cut in the rotor, that's usually something getting lodged between the pad and rotor.

Bad hardware will usually cause one pad to be worn more than the other, or worn at an angle.

I bet if you take off the pads you'll find a rock or some shit. Let us know.

[BreckAConner]

If the caliper is sticking it will do this. Jack the car up and spin that tire, compare to the rest. I'm assuming the groove is where the pads are?

Also ...
- is this the front or the rear?
- is the groove on both sides of the rotor? (if not, which side)
- have the caliper pins been properly lubricated?

1. Front Right
2. Front Side, haven't checked back
3. Greased them when put on, good last time I check them about a month in a half ago.

;3264114]i would say either some debris got wedged in there and became embedded in the pad. That, or the actual pad material itself was poorly mixed and it has a "hard spot". Either way, I'd probably replace the pads.

I'll check and see if something got wedged.

You stated that the pads were a year old and that they don't look worn. What exactly do you mean? Is the thickness of the pad material less than the backing plate?

It's more material than the backing plate.

[deevergote]

Most rotors I've ever owned have developed a groove or two. If it's not extreme, then it's likely fairly normal (for one of the reasons suggested above, most likely.) Can't hurt to inspect the parts and do whatever repairs/restoration/maintenance that is necessary. However, as long as there is no significant abnormal wear elsewhere, and as long as the car stops properly, it shouldn't be anything to worry about.

If the groove is really deep, it may pose a problem, however. A deep groove would likely create a hot spot, leading to overheating the rotors. That could lead to brake fade or cracked rotors... neither are a good thing, obviously!

[Losiracer2]

I'm thinking something got lodged in the brake pad's slot gassing slot. If not that, inspect the pad face for any weird metal pickup of some kind and if you see something stuck, try your best to pick it out of there and then take some sand paper and clean up the surface some.

If you see cracking, then your friction material might be defective or that one spot of the pad was dragging on the rotor causing that groove, so when you let off the brakes, it most likely was still in contact with the rotor.

[BreckAConner]

I inspected the pads, I didn't see anything wrong with them. I'm thinking it had a bur that got stuck in the pad. The spot causing the groove leveled down with the rest of the pad. Hopefully that fixes the problem, this is my first time I've ever seen this happen on any of my cars.