Pad deposits on rotors

[kioneo]

I have OEM pads and rotors, but will soon replace them with ATE PowerDiscs in the front, ATE solid rotors in the back, and (probably) Axxis Metal Master pads all around.

So here is my question.

I went on a "spirited" 10-mile drive today after washing the car and when I got back I noticed clear outlines of my pads on my rotors (all four). It was a clearly defined shape that seemed to be a uniform color (slightly darker than the rotor). I was doing some moderate-to-heavy braking during the drive but tried my best to not come to a full stop with my brakes still applied after braking heavier than normal (i.e. there were a few stop signs and red lights where I stopped, but not after heavy braking), but I bet the rotors were still very warm from previous braking.

Is this normal for OEM pads and rotors considering I was probably using them more aggressively than normal? Will this go away with better quality pads and rotors? Or were the outlines a result of my driving and not the pad/rotor quality?

I appreciate any feedback.

[FenPhen]

I went on a "spirited" 10-mile drive today after washing the car and when I got back I noticed clear outlines of my pads on my rotors (all four). It was a clearly defined shape that seemed to be a uniform color (slightly darker than the rotor).
I've noticed this occasionally on my car's OEM pads and rotors as well (the dark outline of the pads). I had assumed it had to do with washing the wheels. If you drive some more, and do some hard braking, the rotors should come out clean and silver again after awhile.

Minor thread hijack: does anyone else find that when just a little water gets on your OEM rotors, they start to corrode orange within a few minutes? What causes this? Does it make a difference if you dry/clean the brakes right away compared to cleaning the brakes after they've dried (wax and detail)?

[SergioK]

You most likely exceeded the MOT (max operating temp) of the pad. Even if you prevent standing on the brake pedal at a stop, if you exceed the MOT of the pad, and initially stomp on the pedal at speed, it may still leave the imprint on the rotor.

I'm sure you've read this:
The "Warped" Brake Disc and Other Myths of the Braking System (http://www.stoptech.com/whitepapers/warped_rotors_myth.htm)

[kioneo]

Yes, I've read the excellent article.

I have a feeling that the quality of the OEM pads/rotors combined with the fact that the pads/rotors have not been bedded may be the cause.

I will be driving around a bit tomorrow and will observe what happens. I just can't wait to get off of these pads/rotors and switch to something more tuned to my driving style (not to mention reducing the darn dust I have to deal with when washing the car).

Is it ok to perform a bedding process even though these are not new pads/rotors?

FenPhen, I have seen the same orange discoloration immediately after washing or even after heavy rains. I haven't tried drying the rotors, since it seems like a pain in the butt, and the orange color goes away after just a few times of braking. I wonder if it's simply a small amount of rust building up?

[mscoins]

FenPhen, I have seen the same orange discoloration immediately after washing or even after heavy rains. I haven't tried drying the rotors, since it seems like a pain in the butt, and the orange color goes away after just a few times of braking. I wonder if it's simply a small amount of rust building up?
It is a slight surface coating of oxidation which is normal when the rotors become wet. I don't think drying them will help because it seems to happen quickly, at least from what I've experienced when washing the car.

[SergioK]

Is it ok to perform a bedding process even though these are not new pads/rotors?


Yup, you kind of 'have to' on a new car since the brakes have never been bedded in.

[FenPhen]

I haven't tried drying the rotors, since it seems like a pain in the butt, and the orange color goes away after just a few times of braking.
By "dry/clean" I mean applying the brakes a bit of distance to wipe everything off and warm the pad to get rid of the moisture. :)

[kioneo]

By "dry/clean" I mean applying the brakes a bit of distance to wipe everything off and warm the pad to get rid of the moisture. :)

I guess that would be easier than using a towel. :)

BTW, I went out for a drive today and found that after using the brakes with normal to moderate pressure the deposits seems to have mostly dissapeared.

I think I need to do a good bedding process.