A three years field test has been carried out to investigate suitable parameters for wear prediction of spherical roller bearings in railway wagon wheels. New un-destroyed greases of the same composition as in the field test were examined in laboratory conditions using 19 different test methodologies, mainly conventional ones, but also some newly developed. By correlating the results from the laboratory tests with the field test, a specification of testing methodologies for prediction of bearing wear were set up and the connection between the tested parameters were investigated. It was found that a combination of the roll stability test and the limiting shear stress coefficient enables a prediction of bearing wear. One example of another finding is that the bearing temperature could be predicted by utilization of the base oil viscosity