I clean the stained aluminum wheels on my truck with Protect-All. Works quickly. Spray on let sit a minute or two then use a soft cloth to wipe of the product. My wheels looked just like yours. Mine get stained from rain. Frequently after a rain I don't drive for several days and the rain sits there,along with the dirt that comes with it. This IMO is what makes these stains.
Last edited by Hermann; 05/25/20 09:28 AM.