I have a 2005 ultraSupreme with a bedroom slide and a living room slide. The bedroom has been nothing but trouble. The living room slide has been no problem yet. I have had 2 leaks on the bedroom slideout. One was on the box front end and one on the box back end, but at different times (like a year apart). If it’s happened to me it will happen to others. Here’s a few things to look for.
1. The bed sits on the floor of the slide out. On the outside of the slide out check to see if the floor the box is wet or dry rot on the outside. If it is, it means the water is coming down the outside wall and coming into the MH under the box floor and dripping on to the carpet. If it’s not doing this, bonus. If it is wet or dry rot see the following #3 &4. If it is okay see #2.
2. If you think it is the opening seal, tilt the rig so water will flow to the outside edge of the slideout. If this stops it then replace the opening seal and see if that does it. You should play it safe and caulk all the joints on the box as discussed below.
3. My first leak was coming in under the box floor, so I figured it had to be coming down the outside wall, running under the floor and dripping onto the carpet. I caulked all the joints I could find on the outside of the box to no avail. If you look at the construction of the box it is a flat sheet of aluminum with the window in it. The edges slide into a piece of aluminum that has been bent into a U shape with a 90 degree edge to screw it to the box. The mating corners are cut at 45. On the outside corners you see small square plastic panels. These panels use double sided tape to hold them in place. Once I caulked the small plastic panel and the inside 45 degree cut, the leak went away. So, you may want to be proactive and caulk all the joints on the box.
4. The second leak started on the back side of the slide out and was the same as the front side. So I caulked all the joints again with no success. What it came down to was the roof. I got a shower curtain liner from the Dollar store and laid it over the slide roof to keep the water from getting on the roof. Once I did that the leak stopped. As my slide topper needed replacement, I took it off, cleaned the roof and could see my problem.
My MH roof is fibreglass, but the slideout roof is rubber. The U shaped box edging is screwed into the roof. This section is covered by a 4" strip of Eterna Bond tape. Over the years, wear and tear caused the screw heads to break through the tape giving water a way in. I taped over the screws, repainted the roof with a rubber coating, and put the new slide topper on. So far so good.
I live in the Pacific Northwest so waiting for it to rain to see if the leak has stopped is not a problem.
Let us know what happens.