I have used Propack B.E.S.T. 55128 Rubber Roof Cleaner/Protectant with good results. Turns the Dicor from dingy grey to bright white.
For what it's worth, in my opinion roof inspection and continually maintaining the Dicor is the worst part of ownership. While my coach was still relatively new, I cleaned the roof and then applied Eternabond tape over every seam, joint and fixture on the roof. Now I only need to clean the roof once a year and don't have to worry about leaks developing. The only downside is if I need to replace a vent, Winegard Connect, etc., the Eternabond takes some work to remove.
I'm with Fish and Dear..... I also store my coach in a garage up north when we are not using it so I don't have to worry about sun, rain, snow, ice and excessive heat causing extensive wear and tear. I just can imagine keeping my coach stored outside year round in Florida with the summer heat down here. Fortunately we camp in the northern states during the hot months down south.
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