i have the same thing on my aluminum wheels. What i have done it just used a wire wheel and put it on a dremel tool and scraped away. Steel wool works too but takes a little longer. I did use cheepo wheel cleaner, it helped a little bit, but simple green worked even better. I dont have any clear coat on my wheels. You can also go to a detail shop and they have industrial or whatever it is, but is is an acid type and gets it REALLY clean.

kevan

93 rodeo,3.2 manual, limo tint, nice sound system,keyless entry and a killer alarm, drop in K&N, 3 inch DOR lift, 32-11.50 BFG MT's, warn hubs zutah.com wheeler
WELLS FARGO BANK WILL RIP YOU OFF!GET OUT WHILE YOU CAN