Are these rims painted? If not there is this stuff called Eagle One Mag cleaner, I had rims that were sitting in a yard oustide covered in brake dust, dirt, wildlife and other unknown things for 4 YEARS! So i figure its time to clean them, I used Soap + water, a steamer, some orange stuff, paint thinner, mineral spirits, stuff called Awsome (great for everything) and carb cleaner not an ounce of anything came off the rims until someone told me about Eagle one, i sprayed it on and literally in 5 seconds the dirt was coming right off, i did have to do a very little bit of scrubbing then i rinsed them off and now they look brand new................................. I was just told they make this stuff for Painted rims and chrome rims so your chances are looking up i swear by this stuff now. Another example: i have those spoke rims that came on the Regals they havent been clean in 20 years (no joke) i sprayed what i had left of the Eagle one counted to 30 rinsed them and it looked like i just bought them.
WARNING!!
WARNING!! This stuff has 3 different kinds of acids, It does burn the skin and CAN make your bones brittle
Sulfuric Acid
Hydrofluric acid
i forget the other one YOU MUST WEAR GLOVES AND I RECOMMEND GOGGLES! (This stuff sprays from the bottle weird unless mine was gimpy)
Anyway good luck and i hope this helped!
Patrick
P.S. About $6-$7 a bottle used 1 bottle for 4 rims and 4 hubcaps!