I wish it was grime, but the majority of the ugliness is various layers of the worn finish. In the 'before' picture I posted above, the brown crap is brake dust, but if you look closely you can see the missing finish (all of the wheels are like this). I work at a car wash / detail shop, so believe me when I say I used every chemical we have to clean the wheels up before I decided on the refinishing

. After I come back on Monday and have time to do the same to the other wheels, they're going to be babied until I get new wheels someday, and then they will be retired to the garage
