What does 5w40 engine oil mean?
1 Answers
5w40 engine oil means: 1. 'w' stands for winter, indicating it's for winter use; 2. The number 5 before 'w' represents the viscosity at low temperatures - the smaller the number, the better the fluidity in cold conditions and stronger cold resistance; 3. 40 refers to the viscosity at 100°C - the higher the number, the greater the viscosity and better high-temperature resistance. Engine oil, also known as motor lubricant, functions to: 1. Lubricate and reduce friction; 2. Assist in cooling; 3. Seal and prevent leaks; 4. Prevent rust and corrosion; 5. Absorb shock and cushion impacts. The composition of engine oil includes: 1. Base oil: The main component that determines the fundamental properties of the lubricant; 2. Additives: These compensate for and improve any deficiencies in the base oil's performance.