As the "heart" of a car, the engine's normal operation cannot do without the lubrication and protection of high-quality automotive oil. As the core category in the automotive oil system and a key lubricant product for ensuring engine performance, automotive engine oil directly affects the vehicle's power output, fuel economy, and service life. Faced with a wide variety of engine oil products on the market with different parameters, many car owners find it difficult to make an accurate choice. This article will sort out the scientific selection methods from the core principles, key indicators, and suitable scenarios.

When choosing automotive engine oil, the primary core principle to follow is to match the original factory requirements of the vehicle. Different brands and models of engines have differences in design concepts and working conditions, and thus have different performance requirements for lubricating oil. Car owners can refer to the vehicle's user manual to determine the engine oil specifications recommended by the original factory, such as the API (American Petroleum Institute) standard level (such as SN, SP, etc.) and the SAE (Society of Automotive Engineers) standard viscosity grade (such as 5W-30, 0W-40, etc.). Among them, the API level represents the quality grade of the lubricating oil, and the later the letter, the better the performance such as oxidation resistance and cleanliness; the SAE viscosity grade reflects the flow characteristics of the oil at different temperatures. The smaller the number before the "W", the better the low-temperature fluidity, which is suitable for use in cold regions; the larger the number after the "W", the higher the viscosity at high temperatures, which is suitable for high-temperature and high-load conditions. If choosing randomly without following the original factory requirements, even if expensive lubricating oil is used, it may not be suitable for the engine's needs and may even cause wear and carbon deposits. 
Focusing on the core performance indicators of lubricating oil is the key to choosing high-quality engine oil for vehicles. Besides the API and SAE grades mentioned earlier, it is also necessary to pay close attention to the type of base oil and the additive formula of the oil. Base oils are divided into mineral oil, semi-synthetic oil and fully synthetic oil. Among them, fully synthetic oil, with its superior high-temperature stability, oxidation resistance and cleaning and dispersing properties, is the preferred choice for mid-to-high-end models and turbocharged engines; semi-synthetic oil strikes a balance between performance and cost-effectiveness, making it suitable for daily commuting family cars; mineral oil is affordable, but its performance lasts for a shorter period of time, making it more suitable for old, low-load engines. Additives, as the "soul" of lubricating oil, directly affect its anti-wear, anti-corrosion, and carbon cleaning capabilities. High-quality engine oil for vehicles will be combined with precisely proportioned additives, which can effectively reduce internal engine wear and extend the oil change cycle. 
Adjusting the choice of engine oil based on actual driving scenarios and conditions can enable the vehicle's engine oil to perform at its best. If the vehicle is mainly used for urban commuting, frequent starts and stops as well as low-speed driving will lead to an increase in carbon deposits inside the engine. In such cases, fully synthetic or semi-synthetic lubricating oils with excellent cleaning performance should be selected. If the vehicle is often driven on long-distance highways at high speeds, the engine will be under high temperature and heavy load for a long time. In this case, lubricating oils with strong high-temperature stability and appropriate viscosity grades should be given priority. For car owners in northern cold regions, low-temperature fluidity is a key consideration. They should choose oils with smaller numbers before the "W" (such as 0W-20, 0W-30) to avoid poor fluidity of the oil during cold starts in winter, which may prevent timely lubrication and protection of the engine. In contrast, for those in southern hot regions, oils with slightly higher viscosity can be chosen to ensure lubrication performance under high-temperature conditions. 
The last point to remind you is that when choosing engine oil for your car, you should select well-known brand products sold through regular channels to avoid purchasing counterfeit or substandard lubricants. Counterfeit products not only fail to protect the engine but may also cause serious faults such as cylinder scuffing and bearing seizure due to substandard performance, causing significant losses to car owners. At the same time, regular oil changes are also an important part of maintaining engine health. Even if high-quality lubricants are used, they should be replaced in accordance with the original factory's recommended intervals to prevent performance degradation from affecting engine operation. 
High-quality engine oil for vehicles is the "guardian" of long-term engine operation. When choosing, it is necessary to take into account the original factory requirements, the performance of the lubricating oil, and the driving scenarios, so as to select the most suitable product for your car. It is hoped that the selection guide in this article can provide practical references for car owners, enabling every owner to better protect the "heart" of their vehicle through scientific selection of vehicle oil and enjoy a safe and smooth driving experience.