The oil change interval for a car depends on a comprehensive assessment of the oil type and usage conditions. Fully synthetic oil can last up to 1 year or 10,000 kilometres (whichever comes first), featuring a stable molecular structure and strong resistance to degradation, making it suitable for turbocharged vehicles or frequent long-distance driving. However, commercial vehicles exceeding 3,000 kilometres monthly should reduce the interval to 3-5 months. Semi-synthetic oil is recommended for replacement every 7-8 months or 7,500 kilometres, suitable for regular household use, while mineral oil requires replacement every 6 months or 5,000 kilometres, particularly appropriate for older vehicles. Special cases include advancing the first oil change during a new car's break-in period to 2,500 kilometres, and shortening the interval by 20%-30% for low-temperature short-distance driving or extreme road conditions. Note the time-priority principle: even low-mileage vehicles must replace mineral oil after 6 months and fully synthetic oil after 1 year, with simultaneous oil filter maintenance. Strict adherence to the maintenance manual is advised, along with regular monitoring of the oil's colour, viscosity, and contamination levels to ensure optimal engine performance.
