[For the English abstract and full text of the article please see the attached PDF-File (English version follows Russian version)].ABSTRACT The problem of uneven wear of a wheel set is considered by many scientists of the world, in the works related to car building. New software complexes for mathematical modeling are being created, and each follows its own theory of rolling stock dynamics. In this article the main provisions for deformation and wear of a wheel along the circle of rolling during car movement are considered. In this case, the elastic sliding model is described in more detail. During wheel rolling and in the presence of torque in the contact area, there is always a gripping area that is located at the entrance, and an area of slippage at the exit. It is proved that the coefficient of slippage is equal to deformation in the gripping area. Under certain kinematic and dynamic conditions, a stress distribution graph is plotted in the contact zone. On the basis of the theory of tangential stresses, a displacement formula is obtained, which is transformed into a new formula for the creep coefficient, which retains the physical meaning of the value found. Keywords: theory of rolling stock dynamics, wheel set, rail, creep coefficient, sliding, gripping, contact spot, wheel rolling, stress distribution.