This paper will outline the technical challenges experienced and the engineering methods used to overcome them during the endeavor to reduce wheel hub units mass and friction. Results achieved by the project team are significant and have meaningful contributions both to the unsprung mass, inertia and rolling resistance reduction. These features directly enable fuel consumption reduction and related CO2 emissions as well as positively influencing vehicle dynamics.Paper will handle two separate subjects of weight reduction and drag related power loss improvement and their combined effect at vehicle level. It will provide both simulated and test measured data as well as the validation of various features.In the very near future every milligram of CO2 reduction will count. To achieve significant improvements engineers have to think out of the box, develop breakthrough technologies and sometimes totally rewrite the rule book. This paper will outline how the project engineers have approached the problem, used modeling techniques to simulate various solutions, conducted technology scouting, selected new technologies, prototyped and fully validated robust products.