What is the difference between Shell engine oil 5w30 and 5w40?
2 Answers
Here is an introduction to the differences between Shell engine oil 5w30 and 5w40: 1. Different high-temperature viscosity: The difference between 5W30 and 5W40 engine oil lies in their high-temperature viscosity. 5W40 has higher viscosity, providing better high-temperature protection and sealing performance. However, higher viscosity is not always better, as excessive viscosity can negatively impact the engine. 2. Different fluidity: Winter oil grades are 0W, 5W, 10W, 15W, 20W, and 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 applicable minimum temperature. 3. Different usage environments: The difference between 5W-40 and 5W-30 is only in the latter number. 40 can be used in environments with temperatures below 40 degrees in summer, while 30 can be used in environments with temperatures below 30 degrees.
When I ran an auto repair shop, I often recommended Shell engine oil to customers. Both 5w30 and 5w40 are multi-grade oils, performing equally well in low temperatures and flowing easily during cold starts. However, the difference lies in high temperatures; 5w30 is thinner in hot weather, offering lower fuel consumption, making it suitable for new cars or those driven gently. 5w40 is thicker, providing better engine protection under high temperatures, ideal for high-speed driving or older engines, especially in hot summers, as thinner oil can accelerate wear. Always check the vehicle manual for recommendations; for example, Volkswagen cars generally use 5w40, while Toyota vehicles are fine with 5w30. Choosing the wrong oil might save some fuel, but inadequate protection at high temperatures can lead to increased engine noise over time.
