The performance of semi-active differential systems is deeply influenced by the way in which they are actuated. Conventional semi-active systems are actuated by pressure-controlled hydraulic actuators that, despite their good dynamical behaviour, are relatively inefficient. In this work, the authors propose an innovative controlled hydraulic pump solution that is able to drastically improve the efficiency and to reduce the overall encumbrances, maintaining very high performance in terms of dynamical behaviour and corresponding frequency response. The authors investigate design criteria of the proposed solution, describe a simulation model and validate design and simulation models with experimental data.