What does the oil viscosity 5W-30 mean?
2 Answers
In engine oil 5W30, the "5" indicates the oil's low-temperature fluidity. The smaller the number, the lower the ambient temperature it can be used in, and the better the protection for the engine during cold starts. The number 5 represents resistance to external low temperatures of -30°C. The number 30 represents the kinematic viscosity standard at 100 degrees Celsius, which is 30. This number indicates the oil's high-temperature resistance; the larger the number, the better the oil's protective performance at high temperatures. Additional information: 1. The SAE lubricant viscosity classification for winter oil grades are: 0W, 5W, 10W, 15W, 20W, 25W. The symbol W stands for winter, and the smaller the number before W, the lower the low-temperature viscosity, the better the low-temperature fluidity, and the lower the minimum applicable temperature. 2. The SAE lubricant viscosity classification for summer oil grades are: 20, 30, 40, 50. The larger the number, the higher the viscosity, and the higher the maximum applicable temperature. "W" stands for WINTER, and the number before "W" indicates the flow viscosity under low-temperature conditions. The smaller this number, the better the oil's low-temperature fluidity, and the better the protection for the engine during cold starts. The number after "W" represents the oil's viscosity at 100°C. The higher the number, the higher the viscosity, and the better the protection for the engine at high temperatures.
The oil viscosity rating 5W30 might sound technical, but it's actually quite simple. The 'W' in 5W stands for winter, and the number 5 indicates the low-temperature fluidity grade – a smaller number means the oil flows more easily in cold weather, ensuring quick engine lubrication and smooth starts in sub-zero temperatures. The 30 represents the high-temperature viscosity grade, where a higher number means the oil is thicker when the engine is hot, providing better protection and reducing wear. Having driven for years and tried various oils, I find 5W30 well-balanced, especially for regions with distinct seasons – it doesn't freeze in winter or thin out in summer, protecting engine longevity. Always check your vehicle manual for recommended grades; switching arbitrarily may increase fuel consumption or cause part damage. This is crucial because wrong oil choices leading to engine issues can result in expensive repairs.
