Abstract: A base member is arranged to be secured in a fixed position on a vehicle and has a top surface upon which a flat disc of resinous plastic material is seated to form a load supporting bearing. A load plate having a bunk secured thereto is seated on the plastic disc and is connected to the base member for rotation thereon. The base member, together with the resinous plastic disc and the load plate, have a width sufficient to provide sole support for a bunk on the vehicle. Resinous plastic annular rings are secured to the assembly to provide thrust surfaces between the load plate and the base member.