[JRTJH]

There are rubber seals on the INSIDE fascia that seal against the trailer sidewall. If they are "essentially even top and bottom" then the slide is in the proper position. If there's a gap at the top (on the inside) and the seal isn't contacting and compressing the same at the top as at the bottom, then the slide probably will need some adjustment. I'd suggest checking both ends of the slide as there is a possibility that the slide is twisted or racked out of square.... You'll want to assess all four corners on the inside to make sure the slide is fully extended. While you at it, check all four corners when the slide is retracted to make sure it's fully in the travel position as well. Sometimes, when one function is out of alignment, both are.