On my 2002 sunline 267sr I had a lot of black streaks ect. I dont care to use to many chemicals on the siding since I did that once on a coachman and it stripped the paint off
What i have found that works well is mothers cleaner wax. It pulls the black streaks off easily, leaves a very nice even shine and makes future stains much easier to clean off. I know the sunline book says not to use wax, but it has got to be better than a lot of the chemicals in black streak removers. I have used the wax now for two years with no negative effects (except now my wife is used to seeing the camper shiney and wants it that way all the time
) JMHO
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