SUMMARY
The article is devoted to questions of the admitted speeds establishment of various tipes of freight 4 axis cars movement with carriages 18-100 (????-?3), in empty and full a condition. The results of the complex researches of dynamic qualities of the cars are given and their influence on a track is appreciated. As a result of researches it is offered to establish different the approach to an establishment of admitted speeds of movement for empty and full cars.