The Development of Low Friction and Anti-Fretting Corrosion Greases for CVJ and Wheel Bearing Applications

The reduction of fretting corrosion for wheel bearings and vibration for constant velocity joints (CVJ), which occurs during the transportation of completed vehicles, is difficult to eliminate. Our research, using anti-fretting greases for wheel bearings and special greases for CVJ's, has found that the composition of the grease is closely related to these problems. Fretting corrosion for wheel bearings and vibration of CVJ's can be reduced significantly by arranging the composition of the grease with the appropriate additives and thickener. For reducing friction of CVJ's, urea greases can be effectively used when they contain the additives of organic molybdenum compound and organic zinc compound. To improve the fretting corrosion characteristics without reducing rolling fatigue life, urea greases were found to be the best when constructed with additives from the phosphoric family and limiting the base oil viscosity.