Originally Posted By: 99Saturn
Finally got around to taking off my snow tires and took a look at my rotors and saw the below.
What causes this? Rotors are about 2 years old, 6,000 miles.
If you think that looks bad wait till you see the inside side of that rotor.
I live in the Minneapolis area and they salt the [censored] out of our roads, I also saw a lot of this when I owned a hobby Audi repair shop. First off 6,000 miles in 2 year also explains some of it. Looks like your car does a lot of sitting, that in turn means a lot of time to start oxidation. Just saying, you have I would bet 50 to 60% less braking power because of reduced "swept area", you are a danger on the road. When it rains, I always take the car out for a 4 minute ride of heavy braking to clear the rust of from the rain if I know the car will not be use within 1 1/2 days. IE weekends since my car is use as a work car and we use my wife's car more on weekend.
When My Honda was recalled with the airbag recall I was given a loaner car from Honda and was able to park my carin my garage for 3 months will waiting for new airbags. I signed a paper that I was not going to drive it and if I did they were not liable. I did drive my car around the block every 2 weeks to clear the fine rust that was starting.
Ways to reduce this when you get your new brakes:
1) Don't let rust even start after a rain, drive the car with some heavy braking.
2) Become a heavy braker, use them or lose them.
3) Buy coated brake rotors so rust that can start on the outer edge has a harder time migrating inward.
IE EBC brakes or others of the same.(can be electro plated too)
http://www.autoanything.com/brakes/ebc-brake-kits
4) Don't let rust even start after a rain, drive the car with some heavy braking.