I would never use SOS pads on the aluminum, however. To really get your wheels clean (this is labor intensive and NOT fun), you can use Coopers aluminum polish. It is found in most truck stops. I have my tractor trailer polished at the wheel polishers in Arizona and they use a two step process. First, they clean the wheels with hydraflouric acid, which will cause the wheels to turn gray (the acid causes the aluminum to oxidize). Then, you have to really rub the aluminum polish on the wheels until they turn black. Then, take a clean cloth and rub the black stuff off. Unless you are really energetic, I would not do this. ANY type of acid based cleaner will discolor your wheels, so be sure and read the ingredients. I have polished my trailer wheels a year ago, and they still look good. Would I do it again? Nope! Too much work!