A vehicle trailer system for loading, transporting and unloading a load includes a wheeled trailer structure for attachment to a towing vehicle; a carriage mounted for bidirectional travel on the trailer structure; a carriage hitch carried by the carriage, the carriage hitch configured for coupling to the load; a movable, preferably pivotable arm carried by the trailer structure; and an arm actuating cylinder operably engaging the movable arm to selectively position the movable arm in lowered and raised positions. In a first raised position, the movable arm can suspend a cable attached to the load and lift the load when the cable is pulled by a winch. In a second raised position, the movable arm can arrange the cable so that it presents a strong vertical component for lowering the load onto the carriage hitch. When the movable arm is arranged in the lowered position, the carriage can travel over the movable arm as the cable pulls the load onto the trailer structure.