How often do you wash your roof? What you are describing sorta sound like dirt and oxide off the roof. When I wash mine, the water does run white streaks down the side of the camper. I use Tide laundry detergent. It cuts the dirt at least and I keep after it. I wash the roof about every 2 ½ to 3 months. In the winter it might go 3 ½ pushing 4 months.
I also use 303 UV protectent on it and any of the plastic up there. This helps slow down the oxiding that is normal and helps slow down the dirt sticking. It for sure extends the life of the plastic from becoming brittle.
The caulk, YES every time your up there look at it all over. So mine gets that caulk check on the same washing intervals. When any split or hair line crack starts that is the time to deal with it. In the beginning stages they are like splits to an air bubble below some times. I dig down into the split, make sure I get into total good Dicor and then caulk more Dicor over it. You need to keep a few tubes around so when you need it, you got it.
It the TT is stored out side it seems to advance those fine slits quicker. I have 2, 2004 units. One lives inside the other out. The T2499 inside is like new on the roof. I have only had to dress 1 maybe 2, fine slits. The T310 Lives outside. I have had to do several including one rear corner that as I dug I wanted to make sure I got that area perfect.
Good luck and hope this helps.
Current Sunlines: 2004 T310SR, 2004 T1950, 2004 T2475, 2007 T2499, 2004 T317SR
Prior Sunlines: 2004 T2499 - Fern Blue
2005 Ford F350 Lariat, 6.8L V10 W/ 4.10 rear axle, CC, Short Bed, SRW. Reese HP trunnion bar hitch W/ HP DC
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