Abstract
This paper discusses ways to apply mathematical methods to evaluate the results of tribodiagnostics (ferrography) related to vehicle combustion engines. The idea is based on a discriminative analysis which makes it possible to describe one qualitative parameter, i.e., complex technical state of the engine, by means of several quantitative parameters, i.e., quantity of diagnosed wear particles in used oil. The results have been verified by means of considerable statistical data of T3 - 930 engines made in Czech Republic used in trucks and automobiles.