The chassis and frame structure of high-low trailer is more complicated than that of straight trailer. Because it is necessary to support the lifting and fixing of the high-low trailer, the self-weight of the high-low trailer may be heavier than that of the straight trailer.

High and low trailers need more steel and hydraulic systems, and the weight of these materials and equipment will also increase the self-weight of the vehicle. High and low trailers need additional lifting systems and fixed equipment, and the weight of these equipment will also increase the self-weight of the vehicle. 13m direct trailer's body structure is relatively simple, generally there is only one flat car, while the high-low trailer's body structure is relatively complex, generally it is a rugged car, so the self-weight of the high-low trailer may be relatively heavy.