Slideout plastic runners breaking

Usually two screws hold them in place. Lift the carpet and see if you can access them.

You don't say what your unit is or how old.

Replacement is not difficult. With the slide-out open, remove the aluminum trim strip along the bottom of the slide-out end walls. This holds the side of the runner in place. The bottom of the runner is attached with double sided tape, so use care not to damage the underside of the floor while removing it. Probably best to remove a section at a time. The front part of the runner is removed from inside the trailer. Use a bottle jack and wood blocking to lift the slide-out floor just enough to take pressure off the runner. Clean up the surfaces as needed. Remove part of the protective paper off the double sided tape and slide the new runner into place from inside the trailer. Then from underneath, remove the rest of the paper and push the runner into position. Reattach the trim strip and remove the jack.

Yes, I had that happen last year and spent the whole winter figuring out a better system.
The plastic piece on mine was a very specific part and I figured it would be hard to get for a 10 y/o TT and was a bad design to start with. I noticed that the plastic was finally starting to wear into the fabric on the bottom of the slide.
What I did was install 10" long X 1.9" dia conveyor rollers at each end that are capable of supporting 1200 lbs each. The rollers are inset into the floor and let me tell you, the slide works smoother and faster than it ever has before. The design is copied partially from a friends new Arctic Fox TT - though mine is more robust (his collapsed into the floor..).
I made simple brackets to support them and they are hidden under the little flap of carpet at the front edge of the slide. When the slide is all the way in, the rollers set against a 6"X 12" piece of SS plate steal that is attached to the bottom of the slide. This way there is no direct pressure applied by the roller to bottom plywood of the slide.
It was a lot of work but the system is bullet proof.

donn0128 wrote:
Usually two screws hold them in place. Lift the carpet and see if you can access them.

The top is held in by rows of staples every about every 2 feet. Sounds like from the other post the underside is tape.

The plastic runner on the slide out broke off after only camping in it about 10 nights. Mine was still under warranty so they fixed it but doesn't look like a very thick piece of plastic.