Recommendations of the car manufacturer should always be observed. The majority of modern passenger cars and vans require the oil change after driving 15,000 – 30,000 km or after one year. This also depends on oil consumption by the engine as well as the conditions. When driving in the city (small distances, driving with frequent start and stop of the car) and at high engine speed, the engine works in difficult conditions. Therefore, in such conditions a frequent change of oil is recommended, because the pace of engine wear and tear when driving at short distances is even five times higher than in case of driving at high speeds on motorways or expressways.