Is 20W-50 Engine Oil Suitable for Winter or Summer?
2 Answers
20W-50 engine oil is suitable for both summer and winter in southern regions, but not for northern winters. This is because 20W-50 viscosity oil can only be used at a minimum temperature of -15°C, while northern winter temperatures often drop below -15°C. At such low temperatures, the fluidity of this oil deteriorates, which can lead to engine failure to start and other issues. 20W-50 is the SAE standard viscosity value for engine oil, indicating the oil's viscosity. The "W" stands for winter, and the preceding number represents low-temperature fluidity. Common values include 0W, 5W, 10W, 15W, and 20W, where 0W corresponds to -35°C; 5W to -30°C; 10W to -25°C; 15W to -20°C; and 20W to -15°C. The smaller this number, the better the low-temperature fluidity, resulting in smoother cold starts for the car. The number following the "W" indicates the oil's kinematic viscosity at 100°C. A higher value means the oil can maintain its viscosity index better at high temperatures, which can also be understood as providing better lubrication performance under high-temperature conditions. Apart from the numbers before and after the "W," other parameters can also categorize the oil. For example, oils starting with "S" are for gasoline engines, while those starting with "C" are for diesel engines. If both "S" and "C" are present, the oil is suitable for both gasoline and diesel engines. When selecting engine oil, keep the following points in mind: Choose oil based on the engine's requirements. There is no need to use overly advanced oil in engines with lower requirements, nor should you use lower-grade oil in engines with higher requirements. Opt for multi-grade oil whenever possible. Multi-grade oil is economical, long-lasting, and efficient, offering better protection for the engine. Due to its characteristics, multi-grade oil may appear darker prematurely and have lower oil pressure compared to conventional oil, both of which are normal. Be wary of counterfeit oil, as well as oils contaminated with debris or grease, which can clog the engine's intake system and accelerate engine damage. Always purchase from reputable sources to avoid buying fake oil.
For the 20W-50 oil grade, I prefer to use it in summer. After driving for so many years, I've noticed that engines tend to overheat in high summer temperatures, and its high viscosity helps protect components from wear. However, in freezing winter temperatures, the 20W's cold-start performance is poor, leading to difficult starts and insufficient lubrication. I've heard many car owners complain about loud engine noises because of this. Therefore, it's a choice for warm seasons or regions that don't get cold year-round. If you live in an area where winter temperatures often drop below zero, it's advisable to switch to a lower W oil in winter, such as 5W-30, for peace of mind. Changing the oil with the seasons keeps the engine running smoothly and reduces sudden failures.
