My fleetwood had the same problem I replaced the motor at a dealers suggestion no fix. Next I replaced my 8 year old Trogans ( 4 of them) no fix. Finally I had my wife retract the slide while lay under the unit. As the slide came in a foot or so of the lower gasket tried to come with it until it raised then it released and the slide came in. I am now trying to replace the gasket. Of the 14 ft. the two ends seem impossible to install but a friend is going try to help me. P.S. I cut the sagging gasket and it works perfect!