What is the difference between engine oil viscosity 30 and 40?
1 Answers
The specific differences between engine oil viscosity 30 and 40 are as follows: 1. Viscosity: There is a difference in viscosity. The number after 'w' in the oil grade indicates the oil viscosity. 40-grade oil has higher viscosity than 30-grade oil, and they are suitable for different vehicle models. 2. Low-temperature fluidity: The number before 'w' in the oil grade represents the low-temperature fluidity of the oil. 30-grade oil has better fluidity than 40-grade oil, which can reduce fuel consumption more effectively and allow the engine to dissipate heat faster. 3. Comprehensive performance: 40-grade oil also has better quality and overall performance compared to 30-grade oil. Under extremely high-temperature conditions of the engine, 40-grade oil provides better oil stability than 30-grade oil.