Abstract: A mobile vehicle is selectively adaptable for carrying either bulk materials or general freight loads. The vehicle comprises a trailer including a suspension comprising at least one axle with wheels attached thereto and a platform mounted upon the suspension to be carried by the axle and wheels. At least one opening is formed in the platform and a closure or cover is provided for selectively covering or exposing the opening. A framework is mounted upon the platform and a collapsible container is attached to the platform. A hopper or a slope pan is mounted below the opening to define a bottom of the container and to permit unloading of bulk materials. The container is selectively erectable for attachment to the framework and is adapted to carry bulk materials when so erected. The container may also be collapsed and stored within the hopper under the closure so that the platform may be used to carry general freight loads.