What is this?

Hey guys, I have these spots on all 4 wheels. They look like they might be rust, or brake dust, but I didn't think alloy rusted, and I only have disc brakes on the front. Can anybody tell me what caused them and how to clean them off?

Thanks for the help!

 

those look like oxidation. You are right in thinking that alloys don't "rust" per se, but they can oxidize. Without getting into the hardcore science stuff behind what causes it think of it as a form of "rust" that happens to alloys.

Any way check out here for someone who addressed this problem
https://www.tacomaworld.com/threads/oxidized-wheels-dyi-paint-job.233096/

You would pretty much have to sand and repaint them

 

That link helped a lot! Not whole lot of info, but enough, I think. Thanks @district 5!