2013 3001W bedroom slide at front not sealing when out

[larry5167]

Just finished 4 months from pace ,fl. to Quartzsite, az. mule mountain [LTVA] near Blythe ,ca. joshua tree, mojave monument , deathvalley, moab,fruita co.,4courners , dodge city, across ok.,hot springs,ar., columbus ms, tuscolusa and ft. Mitchel al, ft. gaines ga. back to Pace.. 11,000 on truck approx 8,000 on trailer. lot of rough roads.

only problem found when i got home. front slide, bed room , when it is in it is good. when it is out the rear side on top the wiper seal is good at front and is about 1/2 inch off at rear.like the rear of the slide where it meets the trailer has dropped down. take a jack and lift room at middle of slide on back edge til top of slide touches wiper the same all the way across . i can't find any adjustment for just the side . it appears it's missing a spacer.on the rear bottom. tried looking under slide with it jacked up as far as i dare, and cant see anything amiss.
i've went through a few hundred articles in the forum and no help.
no info in trailer manuels that i have it appears to be a lippert through frame electric has round tube and toothed rail in center of slide only adj. i see is up or down on outter end of slide.
slide appears to come in and go out ok it canter levers ok .
when the slide is fully inthe bulb part seal looks to seal fine,, and when fully extended the inner seal looks good .but top wiper doesnt seal from the middle to back edge.
guess i will try to jack up more and try to get better look and see if skid misplaced.

anyone have any pictures of underside of slide..