For the brown stuff on the wheels I used Never Dull. Be gentle if you use it.

 

if they are steel you can also use the scotch brite pads that are from S.O.S. just make sure tha tyou ge the plastic scrubbers version and also dont use the seem ont he wheels as it si real strong and could scratch

But the soap from them is great for this and protects the wheels to.

when your done befor eyou put them on the car or if you want after wards cote the crap out of them with abotu 6 coats each of wax and they will help stay that way for a long time to come