A method is developed for quick oil-quality and performance monitoring by simultaneous determination of the oil's total impurity content based on optical density in the red, green, and blue wavelength ranges, as well as the chemical properties based on the difference in the chromatic ratios and oil color in TCU ( true color units). This method can be used to determine the quality of fresh oil during its production, monitoring the incoming oils before their use in equipment, and make prompt evaluations of the oil's performance in the course of tribojunction use.