Big foot 2000

Even with a bed mat, my father had problems with his 3000 sliding around. We figured it was because of the ultra smooth fiberglass bottom.

He built a 2x6 frame that starts at the back side of the fender wells and goes to the front. The front has a cross bar to keep them spaced. Then he has two pieces which go from the side pieces to the 2x notches built into the side of the bed. This setup only allows about 3/8" clearance on the side of the camper.

We are sure it still moves, but not enough to be noticed.

With the 3000 series, unless you have a full black tank, it will be heavy on the passenger side because of the equipment distribution. He solved that issue by adding air bags and running about 5psi more on the passenger bag.

I would slide some equal size wood pieces on both sides of the camper to fill in void area (2X6's or whatever fits) like KOHLDAD says...

^^^^ This is the easy quick fix.