Abstract: A device for the raising and lowering of a tilting cab of a road vehicle, with respect to the chassis of the vehicle on which the cab is pivoted, permits both lifting and lowering to take place under the control of a manual pump. The cab can also be left in a "floating" condition, when lowered, for the absorption of vibration which would otherwise be transmitted to it by the chassis during running, and in the "floating" condition, exceeding of a certain amplitude of relative movement between the cab and the chassis causes hydraulic clamping of the cab with respect to the chassis. A mechanical locking device may additionally be provided for locking the cab to the chassis in fully lowered condition, and the hydraulic system may permit acceleration of the downward movement of the cab, during lowering, for better engagement of such mechanical locking device.