US Patent 7073847 Duplex door for vehicle

A method and a vehicle door assembly for a vehicle with the vehicle having a cab frame. The vehicle door assembly comprises a door frame movably coupled to the cab frame. An upper door member is pivotally coupled to the door frame. The lower door member is movably coupled to the upper door member. The door frame is movable from a first position alongside the cab frame to a second position inside the cab frame. The upper door member is movable from a closed position to one of an open position and a stored position inside the cab frame.