I have adjusted the super slide on my previously owned 2000 Holiday Rambler Endeavor. I suspect that the procedure is very similar. My system was a Power Gear system, and I have assumed that yours is also Power Gear. It sounds as if your system may need a larger adjustment that what I did to my coach since you're getting some interference due to the sagging.
First go to the link below and download the Power Gear electric slide out systems manual.
power gear slide manualLook in the manual at page 95 that refers to vertical adjustment.
In addition to the adjustment referenced on page 95, there are rollers that also have adjustments. I would try the vertical adjustment as indicated on page 95 first. If this does not fix your problem, then look at the rollers. My rollers were visible from within the storage bins. The rollers were covered by a black plastic box that must be removed to gain access to the roller and adjustment There are large bolts that allow adjustment of the rollers.
There are also rollers within the interior of the coach. I had one roller near the front edge of the slide under the sofa, and another inside a cabinet floor. The rollers on the floor within the interior of the coach are not always depicted on the Power Gear diagrams.
I suggest you make one small adjustment at a time, and then test slide operation. If you don't get the desired outcome, you can then undo your previous adjustment.
The inside rollers work on the top of the floor under the slide. Some of these rollers have been known to deteriorate and shed the outer layer of rubber. Check yours to be sure that they are still in good condition. I think I have seen a reference to a source for the replacement rollers on the Monaco Owners forum on IRV2.
Good luck with your adjustment.
Fred
Fred & Vicki
St. Augustine, Florida