Abstract: A device is disclosed for changing the position of a load-carrying component of a transport unit relative to a support surface on which the transport unit is movable, and in which the load-carrying component such as a chassis frame, is carried by at least one support leg which is provided with at least one contact member for the support surface which may be a wheel, caterpillar chains or a pontoon, or with at least one coupling device. The support leg is mounted on the load-carrying component through an articulation designed and arranged to allow swinging movement of the support leg relative to the load-carrying component. The support leg is connected to the load-carrying component through a power actuator unit which is designed and arranged to swing the support leg so as to cause the position of the load-carrying component to change relative to the support surface to an extent corresponding to the degree of angular motion of the support leg.