Abstract: Waste disposal vehicles are provided with an openable door against which material received in the vehicle body is compacted by an internal ram, the load being discharged at the disposal site by the ram upon opening the door. The compression produced by the ram action expresses liquid from the waste material which pools in the body and leaks out between the butting door and body frames, the leakage increasing under the opening pressure applied by the ram and the pressurized contents, wear and damage to the frames, and relative twisting of the frames. The invention provides an economical, easily maintained and replaced sealing system comprising an expansible seal member, provided preferably on the door frame, and preferably only along the horizontal bottom edge of the door frame and the bottom portions of the two vertical sides, the sealing member thus being U-shaped and providing sufficient sealing to retain any separated liquid.