The Korea Consumer Agency (President: Young-seen Kim, www.kca.go.kr) and the Korea Institute of Petroleum Management (CEO: Seungchurl Kang, www.kpetro.or.kr) conducted a joint test on engine oil of 15 cars of seven different models, that were actually driven by unspecified consumers). 

According to the test results, important properties (in terms of oil quality) such as kinematic viscosity and viscosity index of used engine oil of a car covering 5,000km or 10,000km showed no significant difference compared to those of new oil. And, it was found that it is okay to get an engine oil change at 10,000km despite slight differences according to car condition and driving condition.   

Meanwhile, a survey was carried out to know how often consumers actually get an engine oil change targeting 160 people driving cars. 

According to the survey result, based on traditional information of getting an oil change every 5,000 km, majority of respondents get oil change more often than a cycle (10,000~20,000 km or 6~12 months) in ordinary driving condition recommended by car makers.     

If the change cycle is improved to increase to 10,000 km from 5,000km, the number of times oil is changed can be decreased to once a year, saving US$486mn approx of engine oil change expense every year. Considering the cost of disposing of used engine oil and environmental influence, the effect is even bigger.