What is the difference between Mobil 1 0W30 and 0W40?

[LaSilas]

The difference between Mobil 1 0W30 and 0W40 is reflected in two aspects. Here are the relevant introductions: 1. Different viscosity: 0W30 and 0W40 represent that the viscosity of the engine oil at 100°C is 30 and 40 respectively. The smaller the number before W in the engine oil grade, the lower the low-temperature viscosity, and the larger the number after W, the higher the viscosity. Generally, the letter W will appear in front of the engine oil used in winter; the smaller the number before W, the smaller the low-temperature viscosity, the better the low-temperature fluidity, and the lower the applicable minimum temperature. For example, 0W has better low-temperature fluidity than 5W. 2. Different applicable conditions: 0W30 is more suitable for urban driving, with better fluidity and lower fuel consumption, while 0W40 is more stable under high-temperature conditions and is more suitable for long-distance or high-speed driving.