Just did my roof today. I used dicor spray cleaner and mothers car wash soap. Was fast and easy. Rinse roof spray on some of the dicor roof spray let stand for a min then wash with brush and car soap. Roof looks like brand new.
Then washed the rest of the trailer with meguires wash and wax soap. Shammy dry and all good.
2016 GMC Canyon 2.8 Duramax
Holiday Rambler 187qb.