The notion that compressive residual stresses can extend the service life of components subject to rolling contact fatigue is well documented. However, the exact nature of the relationship between effective case depth and the residual stress state is not well understood for components with case depths greater than 0.050 in. (1.27 mm). It is expected that compressive residual stresses gradually transition to tensile stresses as case depth increases beyond a threshold value. This study will measure the residual stress state of components with different case depths before and after simulated service in order to determine where the compressive to tensile transition occurs. It will also investigate the role of retained austenite and the effect of strain-induced transformation caused by rolling contact. Residual stress and retained austenite measurements will be conducted using X-ray diffraction.