The contribution presents a complete frequency solver workflow applied to automotive transmissions modeled as multi-body systems consisting of mechanical components like rotating rigid and elastic shafts interconnected by gear contacts and supported by bearing joints. Solving the equations of motion in frequency domain based on a linearized model yields the periodic steady-state results very fast compared to transient time integration methods, where fast oscillating components may decay slowly. The frequency domain solver workflow is described in detail from getting a loaded state of the model, which is used for linearization, up to solving linear equation systems for each non-negligible frequency load component. The presented solver workflow is applied to a simple gearbox model. Resulting vibrations from the linear frequency domain solution are compared against results of a transient time domain solution, where the frequency domain solution matches well the time domain results but is obtained within a fraction of CPU time.