US Patent 7631881 Towable wheeled vehicle having a steering axle

A towable wheeled vehicle releasably attachable to a towing vehicle at two horizontally spaced apart points provides a frame supporting a deck, a wheel carriage having a leaf spring suspension and a tubular steering axle with rotatable and turnable wheels at each end, and an electrically powered pneumatic system. Airbags communicating between the steering axle and the frame inflate and deflate to axially rotate the steering axle in axle sleeves carried by the leaf spring suspension reversing the caster and camber of the wheels responsive to activation of the towing vehicle's back up lights.