Oil change interval evaluation of civilian cars in urban traffic condition

Abstract

In this study, it is tried to establish a theoretical model based on oil oxidation stability to evaluate the motor oil life. Five civilian cars and five motor oils were taken to eight road tests. The road tests contained two experiments taken in two test cars with the same car model, synthetic motor oil and test time, and three experiments taken in one test car with the same mineral oil to study the reliability and repeatability of the proposed method. The change characteristics of oxidation onset temperature, total acid number, and kinematic viscosity of test oils were analyzed. A theoretical model was established with the oxidation onset temperature and column chromatography method. The results showed the established theoretical model has the potential to quantitatively determine the remaining service time and operation mileage of the test oils with high accuracy and reliability. The test synthetic oils are able to operate approximately 11,000–13,000 km in 534–686 days in the typical urban traffic condition of China. The test mineral oils are capable of operating approximately 8200 km with 40 km/day or capable of operating 5723 km in 410 days. The proposed approach can provide some reference for end-users to drain their motor oil reasonably.