Abstract: A steerable wheeled assembly for a vehicle such as a harvesting or windrowing machine of the type adapted to be drawn over crop rows in the ground is disclosed. The assembly includes rotatable vertical members and a horizontal axle member which are arranged in a "C" frame supportingly connected to the vehicle and which provides clearance under the axle. Ground engaging wheels rotate on stub axles which pivot in steering movement when the vertical members are rotated. Steering or pivot arms are mounted on each of the vertical members and are connected together by a tie rod. A fluid power actuated cylinder connected to one of the arms is used to pivot the arm and stear the vehicle.