Will Thinner Oils Damage Your Engine?

Summary by Krater

An explanation of motor oil weights and viscosity grades, exploring how they affect cold-temperature engine starting, lubrication, and fuel efficiency.

From the video

Answers: What do motor oil weights and viscosity numbers mean, and how do they affect fuel efficiency and engine protection?

• motor oil viscosity grades
• cold temperature engine starting
• oil film friction and engine efficiency
• oil rating certifications and tests
• hot temperature oil viscosity

What it concludes

• The first number in a multi-grade oil represents its viscosity grade when cold, while the second number represents its high-temperature viscosity grade.
• Lower viscosity oils reduce friction and improve fuel economy by 0.2% to 0.7% compared to thicker grades, though the exact benefit depends on operating conditions.
• Using an oil viscosity outside of manufacturer recommendations can lead to poor cold-temperature starting, bearing wear, or lack of proper lubrication under high loads.
• Car owners should always use the oil weight recommended in their vehicle owner manual.