Abstract: There is described a vehicle or vehicle frame including a first elongated sub-frame and a second sub-frame rotatably connected to one end of the first sub-frame for pivotal movement about the longitudinal axis of the first sub-frame. A walking beam is provided at each of the elongated sides of the first sub-frame in parallel, spaced apart relation thereto. A walking beam pivot assembly extends transversely across the first sub-frame adjacent the other end of the first sub-frame and each of the walking beams is pivotally connected at a point intermediate along its length to a respective outer end of the pivot assembly whereby each walking beam is suspended for independent pivotal movement in its own vertical plane. A connector is provided to join a first end of each walking beam to the adjacent end of the second sub-frame to permit simultaneous pivotal movements of the walking beams and the second sub-frame in their respective, mutually perpendicular vertical planes.