Abstract: A vehicle is disclosed including a load carrying box for the transport of material to a work site in an over-the-road manner. An auxiliary drive and steering system operates at the site for control of vehicle speed and direction with the vehicle operator re-located out of the vehicle to monitor material discharge. The motor drives the vehicle through a gear reduction unit and power transmission component powering a tooth plate clutch mounted on a driveline segment. An engine powered hydraulic pump provides an auxiliary drive bi-directional motor with a remotely controlled directional valve regulating motor speed and direction. A motor control circuit also includes counterbalancing valves served by the directional valve and a torque relief valve dissipating motor torque at the end of an auxiliary drive operation allowing clutch disengagement without risk of clutch damage.