David,
Check check the rollers under your slide. I think that your model coach has a roller with a covering that fails and lets the slide drop when it comes off of the roller
If that is what has happened, you can repair it by replacing the roller or taking the roller and cleaning the aluminum core and pressing a piece of schedule 40 PVC pipe of the right size and length over it to replace the covering.
Gerald
Thanks.
I see such rollers under the passenger side (sink, stove, etc.) slide but not the carpeted driver's side, which is the unlevel one.
Your post, however, prompted me to look more carefully under the slide, and I now see adjustment slots in the plates that bolt the ends of the toothed guides to the outside walls of the slide. It looks like it can be adjusted. Not by me, though.