When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I'd say try to get ahold of a pressure washer and see what that does. Or go the the self serve car wash and use the high pressure water there, might work.
I have this same problem.... i tried with a pressure washer but when the water dries you can still see where the mud has been. It's alsmost like the Rhino has gotten stained.