Discussion on the influence of driving parameters of civilian cars on motor oil degradation

Abstract

Although the reason is not clear, mileage is commonly recommended as an indicator to evaluate the oil drain interval of a car. This paper tries to investigate whether the mileage is the most suitable indicator to evaluate the oil drain interval based on scientific experiments and data analysis method. Three civilian cars and motor oils (contained mineral oil, semisynthetic oil, and synthetic oil) were subjected to road tests under urban traffic condition. The real-time driving parameters comprising speed, mileage, idle time, engine operation time, and number of starts were obtained by on-board diagnostic system. Synchronous oil samples were collected about every 30 days. The physicochemical properties and component changes of experimental oils were analyzed in laboratory. The effects of driving parameters on oil properties were studied with the improved grey relational analysis method. The results show that the influencing factors of driving parameters on motor oil degradation were different in different experimental cars. The influence of mileage on oil degradation was not obvious. The idle time of engine, engine operation time, and number of starts were the three most significantly influential factors on oil deterioration after comprehensive analysis of the three experimental cars.