i had a leak from my ac vent in the bedroom on my rockwood 8315SS after a hard rain. thoroughly checked all the seams and eternabond tape around all the roof vents,ac ,skylight and frig vent. finally found the source of the leak....water was seeping into the screwholes on the side trim at the top of the side.see attached pic of my neighbors trailer,(he had the same problem) we replaced all the screws with stainless steel,put sealant on them before we screwed them back in and made sure they were tightened to pull the trim tight against the side.
i have not had any leaks since the repair.
2008 rockwood signature ultra lite 8315SS[SIGPIC]