Assessment of the kinetics of changes in selected physicochemical indicators of engine oil in operation

The article presents the results of operational tests of engine oil, including the observation of changes in the values of selected physicochemical parameters of oil in subsequent operation cycles, in accordance with the service life specified by the vehicle manufacturer. Preliminary analysis of defined indicators characterizing the condition of engine oil were performed in terms of their suitability for the ongoing monitoring of the technical condition of the engine. On the basis of the values of selected indicators of fresh oil recorded in the course of operational tests and during replacement, one indicator was selected, the kinematic viscosity at 100°C, for which an unambiguous trend of changes was observed during the tests. The last stage was to verify the hypothesis about the correlation between the observed changes in the value of the indicator and the mileage of the engine-vehicle.