What is the difference between 5w20 and 5w30 engine oil?

[MirandaDella]

The difference between 5w20 and 5w30 engine oil lies in their viscosity: 5w20 has lower viscosity, ranging between 5.6 to 9.3; whereas 5w30 has higher viscosity, ranging between 9.3 to 12.5. The number following the 'w' in 5w20 and 5w30 represents the high-temperature viscosity. The higher the viscosity, the better the sealing performance. However, higher viscosity is not always better, as it increases friction and results in greater engine power loss. Engine oil, motor oil, or engine lubricant is a substance enhanced with additives in base oil, primarily containing anti-wear additives, detergents, dispersants, and multi-grade oil viscosity index improvers.