Here's what Mickey thompson recommends for their uncoated Al wheels...
1.
Only wash your wheels with mild soap and water, then hand dry with a soft towel. Some commercial wheel cleaners and soaps, both for home use and at car washes, use acid or caustic chemicals and will damage the wheels. Wash as often as needed to remove brake dust and road dirt and grime before it accumulates on your wheels.
2.
When you first get your wheels and at least after every fourth wash you should wax them with a wax developed for custom wheels. This will help seal the pores and prevent corrosion.
3.
In areas where salt or sand is used on the roads in the winter, the wheels should be removed and stored until winter ends.
4.
We provide steel center caps free of charge with every wheel purchase. These caps will rust under harsh conditions. However, aluminum center caps are available at an extra cost.
5.
If corrosion has occurred on your wheels there are several off the shelf products that will help to restore the factory finish. Another option is to use 000 steel wool and WD40 to remove the corrosion, washing, and then polishing the wheel to restore their luster.
My fronts are fawked with brake dust and road salt and they're just over a year old. Tried a powerball and it did nothing, going to try the steel wool soon.