Originally Posted by Passaro
Bob... it seals at the top, not the bottom but I will look.
Sorry, somehow I misread your description.
Either way, the problem would seem to be that the slide isn't parallel to the wall of your motorhome. In your case, the outside bottom edge of the slide would be too high instead of too low. There might be a clue in the fact that it came on rather suddenly and not gradually as something became worn. Maybe a broken adjustment bolt? Good luck and let us know what you figure out.