No, these are deep pits, major areas of the tin worm. Particularly
noticeable after driving on a snowy day then leaving town for a week or
two for someplace sunny.

David Lesher wrote:
RoyJ writes:

We get some similar issues in the rust belt. Driving around all winter
in the salt spray leads to corrosion on the slide pins. This means the
piston side of the rotor takes all the wear, the opposite side gets
minimal wear. Then let the vehicle sit for a few days, you get heavy
rust pitting. In the winter, you never get to really hit the brakes hard
so you never really wear off the rust pitting. The fix is to lube or
replace the caliper mounting pins.

I grew up in the rust belt and am WAY too familier with that issue.
Idle rotors do get surface rust, but it's gone after a day's use.

This is quite different. No seized pins, stuck calipers, etc.

I'll see if we can get pictures.



As for turning brake rotors, I've not had good results for high
performance vehicles. We usually see rotor warpage within a few thousand
miles. For track usage I'd go with new ones. I know, lotsa $$$ but it's
the only way to get the safety factor back where it should be. BTDT: ex
crew chief on a Porsche GT-3 Cup car.

He's replaced the rotors but we remain curious.