The noise made from transmissions system of a vehicle is one of big worries of automobilist industry. This kind of noise also known as “Transmission Noise” is totally related to limitation of drive comfort. Actually there are different types of noise from transmission system, one of these is known as “Whine Noise”. Because of the vehicle market competitive and of the raise of customers demanding find a solution to eliminate or to decrease these unpleasant effects became an important job. In this sense, this work describes a new methodology for identification of main reasons responsible for Whine Noise in prototype of a popular passenger vehicle through the Numerical and Experimental Confront. In this study were used techniques of Operational Modal Analysis (ODS technique), Numerical Simulation, Vibration and Noise Analysis.