what can't you use wheel brightener on?

anything i should watch out for? any tips on suggested ratios? thanks

 

I wouldn;t use it for anything not from the factory. If you don't know, call the wheel maker and see what they have to say.

 

Even a pH 5.0 acid with a dilution rate of 4:1 (as recommended by Meguiar's for their Wheel Brightener (Ammonium hydrogen fluoride [NH4] [HF2]) results in a pH 4.5 solution. The dilution of an acid doesn’t make it safer as the addition of a molecule of water to a chemical compound, without forming any other products is known as hydration (i.e. dilution causes the pH to decrease) But since pH is not a very good indicator of the strength of the acid in every system, this approach won't always produce the desired results.

Wheel Cleaners- http://www.detailingbliss.com/forum/f35/wheel-cleaners-1201.html

Acid wheel surface damage - Boxster Wheels looking grim - Detailing World

 

Anything uncoated, anodized or that you're unsure of. You need to *KNOW* what the finish of the wheel is before you use anything more than soap and water.