Describes a testing method and sets the acceptance criteria for the determining of the lubrication ability of lubricating greases intended for the lubrication of axlebox bearings. The lubricating ability, primarily related to the capability of lubricating greases to protect against wear, is determined in a roller bearing lubricant test rig. Wear of the rolling bearing rollers, the frictional behaviour and temperature during test are used to discriminate between lubricating greases.