This work deals with the assessment of the yaw moment control via active differential effects to the heavy commercial vehicle dynamics. Summarized are the findings about design of active differential, control algorithms and theoretical assumptions about overall effects to the vehicle dynamics. According to the described theory the own concept of the active differential for experimental heavy commercial vehicle is proposed. The main part of the work is focused on the effects of the active differential on vehicle manoeuvrability, controllability, stability and limits analysis. For this purpose, multibody dynamic model of the complete vehicle with standard open differential is assembled and results of the selected manoeuvre simulations validated by measurements of the real vehicle characteristics. The validated vehicle model is then extended by the model of the active differential with control algorithm. According to the simulations results the theoretical presumptions are confirmed and the effects of the active differential on vehicle dynamics in steady and transition states are evaluated. Based on the described findings the overall improvement of the vehicle dynamics by this technology, feasibility of the proposed concept and main advantages and disadvantages are evaluated.