Well, the good people from P21S were nice enough to send me some of their wheel cleaner after I finished the testing of their beta wax. Of course, I had to try it as soon as I got home!
So the Explorer went on jacks and off came one of the wheels. Mind you, these wheels have NEVER been washed since it was bought in 2001. Yes, they were very dirty!
My process was:
1) Wash w/ Simple Green (5:1)
2) Clay with Zaino Z18
3) Spray on P21S Wheel Cleaner Gel and let sit for 45 minutes
4) Use sponge to rinse
Now, I have to tell you that Simple Green didn't put a DENT in it. And claying it was very tough.
But the P21S Wheel Cleaner is a miracle product. After waiting for 45 minutes, all the dirt just washed off using a running hose. Some spots needed some help from the sponge, but look at the results and judge for yourself.
It's not cheap, but you don't use a lot of it. I rate it a solid 9 / 10!
Here she is, sitting proud on my top shelf...
Letting that products SOAK!!!
Review: P21S Wheel Cleaner (Gel) 
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