What is the difference between Shell engine oil 5w30 and 5w40?
4 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.
My ten years of driving experience have taught me that oil selection makes a significant difference. Shell 5w30 provides quick vehicle response and easy starts, making it fuel-efficient for short city trips. 5w40, on the other hand, feels heavier, offering more stable engine sound and better protection during summer or highway driving. Both perform well in cold starts, but their high-temperature protection differs greatly: 40 is thicker at 100 degrees, preventing wear, while 30 is thinner, suitable for gentle driving. Don't just opt for 30 in high-temperature areas for fuel savings; it might cause engine overheating. Adjust your oil with the seasons—30 is fine in winter, but switch to 40 in summer or for long trips for better reliability.
When I first bought a car, I didn't understand either. After researching, I discovered the secret behind oil labels. The smaller number in 5w30 means it's thinner and more fuel-efficient. The larger number in 5w40 indicates it's thicker at high temperatures, protecting the engine. For daily driving, 30 is suitable for most new cars, offering quick starts and low fuel consumption. 40 is safer in hot weather or during aggressive driving, preventing excessive friction. Just follow the manual and you won't go wrong; don't change the type arbitrarily to avoid affecting engine lifespan. Basic rule: use 30 for mild conditions, choose 40 for high-intensity driving—simple, right?
