Automotive engine oils are primarily categorized into three types: mineral oil, semi-synthetic oil, and fully synthetic oil. Mineral oil is more cost-effective and suitable for micro or economy cars with lower emission standards and modest power performance; It is best to replace it every 5,000 kilometres or 6 months. Semi-synthetic oil, a blend of mineral oil and synthetic base oil, offers superior performance to mineral oil at a moderate price point; it is ideal for household vehicles equipped with small naturally aspirated engines, with a replacement interval of approximately 7,500 kilometres. Fully synthetic oil, produced through chemical synthesis, exhibits exceptional performance across high and low temperatures along with superior oxidation stability; it is especially suited for turbocharged engines or high-performance vehicles, allowing oil change intervals to extend beyond 10,000 kilometres. The number following the "W" (e.g., 30) indicates high-temperature viscosity-the higher the number, the greater the protection under high-temperature conditions. All-season engine oils (e.g., 5W-30) are versatile and adapt to a wide range of climatic conditions, making them a common choice for most vehicles. When selecting engine oil, consult the vehicle manual for the recommended API grade (e.g., SN) and viscosity specification, while also factoring in mileage, vehicle age, and local climate to ensure optimal engine lubrication and protection.
