SUMMARY
In the paper the results of experimental research of wear character and value of responsible tribosystem of cylinder-and-piston group and crank-and-conrod mechanism of diesels for the special self-propelled railway rolling stock are presented. It is shown that the character of wear of cylinder shells and crankpins affect negatively the technicaloperating parameters and limit the resource of diesels as a whole. The wear value is proportional to operating time of diesels, but there are the cases of considerable deviations of value and intensity of wear of parts of responsible tribosystems, which affect the set resource of diesels before a major overhaul.