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Although I have never owned a SR, I believe the slide rooms do not have a rubber roof. I think they are fiberglass, but I'm not sure. The seal for the room needs to seal tightly, and I don't think that would be possible with a flexible rubber roof. If you don't get around to fixing the leak ASAP, make sure you keep the slide in when you don't use it.
2007 T-286SR Cherry/Granola, #6236, original owner, current mileage: 9467.8 (as of 5/26/19)
1997 T-2653 Blue Denim, #5471
1979 12 1/2' MC, Beige & Avocado, #4639
Past Sunlines: '97 T-2653 #5089, '94 T-2251, '86 T-1550, '94 T-2363, '98 T-270SR