Proposed paper deals with experimental tests performed on the Nieman M01 FZG test rig. Experiments were carried out in accordance with STN 65 6280 standard for FZG scuffing tests, from which load values for each load level were obtained. HCR gears made of 16MnCr5 material were utilized during experimental tests. Gear surface was deposited by PVD coatings of nACRo4 and TiAlN + DLC. Conventional lubricant MADIT PP 90H and biological lubricant OMW Biogear S150 were selected for lubrication environments. Aim of the experimental tests lied in application and comparison of PVD coatings deposited on HCR gears. Values of the maximum height of the assessed profile Rz for tip and reference diameters were measured after each load level. Results of experimental tests were statistically processed and relations between the maximum height of assessed profile Rz and load levels for both utilized coatings in both environments were established on the basis of these results.