X3000 6x4 Dump Truck for Wet Clay and Cohesive Soil, 22 CBM Rounded Bed Half the tipper trucks sold into humid regions come back with a bed full of dried clay. This X3000 6x4 is set up specifically for cohesive material: the 22 cubic metre body uses a rounded bottom with no square corners, and the inner surface carries a 4mm anti-stick polymer liner that clay slides off instead of packing into. A rear tailgate with an adjustable rubber seal keeps slurry inside on the road.