Tonal noise such as motor whine and gear whine is more prominent for an EDU in HEV or EV. Gear whine originates mainly from the variation of stiffness during the meshing cycle, which is defined by the gear geometry and by the contact behavior between gear teeth. Structural response of the powertrain to these excitations can result in excessive noise which can negatively affect customer satisfaction. In a typical gear design process, gear microgeometries are essential design parameters to reduce gear whine. At the same time, it influences strength and durability performance attributes such as the gear tooth contact stress. Even though the gear pair design guidelines are well defined in the standards and gear handbooks, the design objective to increase EDU performances at a system level still depends on the designer’s skill and experiences. This study will focus on the microgeometry optimization of an industrial EDU use case with the objective to reduce noise and vibration levels and the validation of the results using a multibody and vibroacoustic simulation within same framework. The main purpose of the optimization is to minimize gear excitation forces while maintaining the gear face load factor. Two different complexities of the same electric drive unit are considered for optimization with the purpose of demonstrating how system level behavior influences the optimum design. An example drive unit model is taken from an industrial EDU. The optimization framework presented allows a systematic approach to find the optimum design considering full transmission system level behavior