<p>The paper discusses the problem of performing qualification sedimentation stability tests of paraffinic gas condensate aiming at selecting the most effective depressor-dispersing additive for transportation of raw materials by railroad transport in the cold season. It is shown that the methods of determination of low-temperature properties (pour point, sedimentation stability during cold storage) used for analysis of diesel fuels cannot be fully applied in testing the resistance to stratification of gas condensate mixtures in conditions of transportation by rail. The paper proposes a method for testing paraffin raw materials in railroad tank car simulators with estimation of the volume of non-dissolved residue, under realistic conditions. Comparison of the results of laboratory tests of gas-condensate mixtures containing four different depressor-dispersing additives with the pilot-scale tests data showed satisfactory correlation.</p>