I have driven all winter and noticed during the winter that every time I washed it, the entire back (window as well) would not come clean at the car wash. Now it is time to Zaino it, but before that I went to wash it and even hand washing and scrubbing, this dull film will not come off. I have a silver 2001 and live in Calgary, Canada, so I am hoping that some of you who live here or in the Northern States who have to deal with road salt etc. may have a solution to this problem. I hoping there is a product out here that will work on this. I cuold not see this problem posted on earlier threads.