If you are seeing cieling paper rolling back, that is a heads up for sure. If it is near a light fixtiure or even near by, take the light down and pock around in side feeling/looking for wet insulation. If you have a problem, now is the time to deal with it. If it festers for 6 months to a year the repair get's a lot more involved.
As to the caulk, see here this may help. Like Gene said if your camper starts getting 4 years old and is outside a lot, odds are rising quick that cracks are forming. One wants to be up on the roof looking 3 to 4 times a year. Especially in the fall before winter and then again in the spring after the thaw out. The key is, you see the smallest split, deal with it then. They only get bigger, never smaller.
If you find a wet problem and need to help, posts some pics so we can see what you are upagainst and help point you where to start the hunt.
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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