What is the difference between 10w40 and 10w50 engine oil?

[LeDonovan]

10w40 engine oil and 10w50 engine oil have the same low-temperature flow performance, but different viscosities, with 10w50 engine oil having higher viscosity. The following are details about engine oil: 1. The "w" in the engine oil model stands for "winter": If the engine oil model contains "w", it means the oil can be used normally in winter. 2. The number before "w" represents the low-temperature fluidity of the oil: 10w means the oil can flow normally at -25 degrees Celsius. 3. The number after "w" represents the high-temperature viscosity of the oil, with a larger number indicating higher viscosity: Generally, naturally aspirated engine vehicles can use 30 viscosity oil, turbocharged engine vehicles can use 40 viscosity oil, and high-performance, large-displacement engines require 50 or 60 viscosity oil. Therefore, when choosing engine oil, it is essential to select the appropriate oil based on the technical characteristics of the car engine, otherwise it may affect engine performance.