Most detailing shops that use acid don't use it as stronge as when they buy it. My friend who has a shop gets it and cuts it himself, so it's not as stronge. I've been using it on my rims all the time and it works great. It takes off all of the brake dust without having to scrub the wheels and it's safe for any wheels with clear coat. You could try some Meguires brake dust remover and some elbow grease, or some other stronge brake dust remover from any auto parts store. Just some helpful hints,
Lata,