slide out scratching floor

Make, model, year? Picture would help or what do you see or feel?

My slideouts (Winnebago Vista) have carpet covered blocks attached under them that slide on the vinyl floor. One of mine had lost one of it's two attachment screws and was wobbling around. I caught it right away and fixed it before it did any appreciable damage. Made me aware I need to keep an eye on them and I expect sometime in the future replacing the carpet is in the cards. Not sure what your's uses to slide across the floor without marking.

There are som many different designs that it's impossible to say without more info and a pic.
There probably is something that can be done though.

Could be something stuck under the slide, could be a screw sticking out, could be an adjustment needed. Hard to say without seeing it.

I had a slide scratching the floor and it was the head of a screw that had backed out. The slide had to be removed to fix it.

make sure you sweep or vacuum the floor properly before you ever close the slides, I had a few rocks make huge gouges in my floor while opening the slide on my last unit, since then I always am anal about cleaning the floors before closing the slides. otherwise the slide bottom shouldn't be touching the floor but with so many designs out there I can only comment on the ones I've owned or seen myself.

I am thinking of having slide removed for same reason
Is it very expensive

Once it moves about a couple inches, I put a throw rug under the leading edge to protect the laminate flooring I installed

After trying the other good suggestions by other posters and IF you can't find an answer order some "slide slickers". They are long vinyl things that lay on the floor as the slide comes in and prevent scratching. I ordered some after we removed the carpet in the living room and adjusting the slide did not solve our scratching problem. I think I ordered them from Tweety's