Friction torque in rolling bearings lubricated with axle gear oils

As a part of the main research project within the aim of increasing significantly drive axle efficiency, this work focuses on rolling bearing friction torque lubricated with five fully formulated axle gear oils with different viscosity and different formulations. The lubricant tribological behaviour in different rolling bearings was analyzed. A modified Four-Ball Machine was used to test the rolling bearings. The effect of speed, temperature and axial load on rolling bearing friction torque was assessed. Experimental results for the internal friction torque were validated with an SKF model. Direct comparisons in terms of friction torque between axle gear oils when they are lubricating different rolling bearing types are presented and discussed.