Abstract: A vehicle including a receiver for tracking signals generated by a wire for directing the vehicle to follow the wire which loops between loading and unloading positions. Sensors detect the vehicle for moving a swingable member to a first position and locking the member to cradle the load on the vehicle. Drivewheel assemblies arranged along one longitudinal side of the vehicle are rotatable to steer the vehicle and to move the wheels to a position to move the vehicle sidewise for delivering the load to a utilization device at the unloading location. The side of the vehicle opposite the side of the drive wheel assemblies is provided with caster assemblies enabling the side of the caster assemblies to be of a significantly reduced height relative to the opposite side thereof to permit the load to be dispensed and enable the vehicle to be withdrawn from beneath the load when the lifted swingable member is lowered.