What does 10-40w engine oil mean?
2 Answers
Currently, there is no 10-40w engine oil, it should be 10w40 oil. 10w40 oil means this lubricant has a minimum applicable temperature of -25°C in winter, with a kinematic viscosity of 40 at 100°C. Engine oil, also known as motor lubricant, serves functions such as lubrication and wear reduction, auxiliary cooling, sealing and leak prevention, rust and corrosion protection, as well as shock absorption. Engine oil consists of two main components: base oil and additives. Base oil is the primary constituent of lubricants, determining their fundamental properties; additives compensate for and improve deficiencies in base oil performance, imparting certain new characteristics, making them an essential part of lubricants.
In my daily driving, I often encounter the issue of choosing engine oil. The 10W-40 is a common grade, indicating the oil's viscosity at low temperatures is 10 (the 'W' stands for winter). A smaller number means faster flow and smoother cold starts, while the high-temperature viscosity of 40 ensures a thicker oil film to prevent wear. I've used this oil for years, and it's suitable for most family cars in regions with distinct seasons, avoiding hard starts in winter or engine overheating in summer. It generally performs well in temperatures ranging from -20°C to 35°C. However, be cautious: excessively high viscosity can increase fuel consumption, while too low viscosity may offer insufficient protection. Regularly checking oil levels and changing it every 5,000 kilometers is crucial. Don’t forget to refer to your vehicle’s manual to confirm compatibility. Choosing a brand with API certification ensures reliability, balancing performance and cost-effectiveness.
