Plane bending fatigue tests have been started on 21NiCrMo2 and 35MnVS4 steel in R=0 stress ratio condition. Using a RUMUL Cracktronic resonant machine equipment with a 160Nm load cell and capable of a working frequency of around 100Hz the fatigue strengths at 5E6 cycles are systematically defined. Insights gained of the multi-facetted analysis performed on the samples (e.g. notch roughness & radius, core/ surface microstructure, hardness profile) further pave the way for realization of gears with top in-service performance developed for hybrid and electric vehicles.