Getting rust marks off rotors


#1

I know this isn’t a big deal, or don’t think it is, but I have rust spots all over my rotors, is there a way to remove that and or does it harm the rotors or impact your braking ability?


#2

Use the brakes.


#3

I do, yucky rust stains still there…


#4

What my friend @texases is saying is that rust of this kind is inevitable and normal. The rotors are going to rust every time the car doesn’t get driven, and driving the car will scrape the rust off by way of the brake pads.

I personally get a lot of rust on my brake rotors, because I prefer to ride a motorcycle when weather permits, and because my car sits near the ocean (even if it only sits overnight). It’s nothing to worry about. It’s part of the reason machining or replacing the rotors has become part of a normal brake job, not just replacing the pads.


#5

As for your braking ability, surface rust won’t affect anything. If you have major pitting, then maybe there would be a reason for concern. Can you upload a picture?

Most likely you’ll just have to live with this. Maybe you’ll want to try a different brand of rotor the next time they’re replaced, as rotors seem to vary in how much they rust while sitting. If you normally drive around town, you could see if making a few stops from high speed on the highway makes any difference, although it probably won’t.


#6

If you rotors are still rusted after driving and applying the brakes several times, I assume your rotors are pitted. This could be caused by weak manufacturing processes or your car is not driven very often. Most rotors have extensive rust around the outer edge of the rotor; the part that does not make contact with the brake pads. As long as your brakes work I would not be too concerned about it. Once your brakes start making rumbling noises it’s time to get them replaced, including rotor, with quality parts.


#7

+1 to Kurt’s post.

The rust is not a removable surface coating; it’s oxidization of the iron in the rotors. That does not mean it’s a problem. It’s pouring out where I live today, and I have to run some chores. I have no doubt that by the time I exit the store, there’ll be rust on the surface of my rotors. It’ll disappear as soon as I use the brakes.


#8

You can buy coated rotors that adds an anti-corrosive coating to the rotors BUT where the pads rub, that coating will rub off and the bare iron will remain and it will rust. Some use better quality of iron but they all rust anyway.

That said, some brake pads have better cleaning properties than others. They wear rotors faster as a result but tend to clean off the friction surface better. It would take a lot of research and maybe a bit of trial and error to find pads better at cleaning. Probably not worth the effort, IMHO.


#9

I’ve seen stainless steel rotors advertised, but they were very expensive and I have no idea if they’re any good or not.


#10

[quote=“the_same_mountainbik, post:9, topic:95724, full:true”]
I’ve seen stainless steel rotors advertised, but they were very expensive and I have no idea if they’re any good or not.
[/quote]They are frequently used on boat trailers that are dunked in saltwater.