So far we have not done anything. We paid for an exterior and interior protectant, can not remember the name of the product the dealer sold us, it was our understanding that the protectant would eliminate the problem we have. As mentioned, our 2008 looked better after 3 1/2 years than this one does after 3 months. The reason we have not attempted doing our own cleaning is I am not sure what to use and also did not want to do anything to cause issue with the warrenty related to the protectant.