The present invention discloses a method for optimizing the efficiency of a vehicle powertrain, the powertrain including an engine, operable to provide electrical power to the motor to the at least one wheel of the motor output torque and the power operation. The method includes generating a three-dimensional view in a plurality of predetermined plurality of source power for optimum engine power and the vehicle speed of the vehicle combination. It corresponds to each three-dimensional view of a predetermined power supply. Means for determining three-dimensional view for a given source power, the vehicle power given optimum engine speed and a given vehicle speed. The present invention can optimize the efficiency of the vehicle powertrain.