Once the clear coat goes, and they start oxidizing, there's not much you can do for them. I took my rear one off and sent it to a guy in Pasedena and had it chromed for $400, including shipping, and he polishes the rough stuff smooth and then chromes them.
Stays clean pretty easy now.

 

One of my previous metrics had solid cast wheels that were very prone to corrosion... I used a Mother's Power ball to clean them up

John

 

I'll have pics up of mine son. Just had it powder coated matte black. Easy maintenance just wipe down and your good to go. No scrubbing needed!

 

The orange shop hand cleaner and a shop rag will do wonders cleaning the grime off of the wheels without damaging them. We stumbled on this trick after trying everything else in the shop. Hope this helps

 

Thanks John. I am going to try that out. My back rim is a mess.

 

your welcome,, also check out this info:

http://www.s10forum.com/how_to_polish_aluminum_wheels

John