The one on the top left of the picture I posted, you can see how the inside and even parts of the face are darker than the other 3... There's a layer of what looks brownish like oxidation/rust, maybe about as thick as a thin sheet of paper all around.
Ive been putting meguiars all wheel on it, scrubbing with a soft bristle wheel brush and rinsing for awhile and it seems like it coming up slowly. Where there was only black/brown before, silver is showing through in spots.
One thing I'm not sure about though is it seems like in the inside of the wheel, it's totally coming up, revealing smooth silver, but the parts on the face of the wheel seem like the coloration is coming up but the bumpiness is staying in some spots.
