I find that using WB on wheelwells works wonders. After spraying the wells with a 4:1 dilution, I let it sit for no more than 30 seconds or so and proceed to pressure wash it off. Afterwards, I can rub my finger on the inside of wheelwells and not get any film of dirt on it usually without having to agitate, unlike any other APC I've tried. Super Clean can accomplish this too at times, but definitely not at a 4:1 dilution ratio. It almost has to ful strength for me to get the same results. Anyone else use it on wheelwells also?