Abstract: A hydraulic tilting device intended to be fitted on a vehicle with a tiltable cab for the purpose of tilting the tiltable cab. The tilting device has a hydraulic tilting unit with a double-acting hydraulic tilting cylinder for tilting the cab, and also a reservoir and a pump. The tilting device furthermore has an additional hydraulic cylinder, for example a locking cylinder, which additional cylinder is connected to the tilting unit via a system of lines. Each of the connecting lines comprises a part associated with the additional cylinder and a part associated with the tilting unit, which parts can be coupled to one another by a disconnectable coupling.