What are the Five Oils, Four Filters, and Three Fluids?

[StNolan]

Five Oils, Four Filters, and Three Fluids respectively refer to: 1. Five Oils: engine oil, power steering fluid, transmission fluid, clutch fluid, and brake fluid; 2. Four Filters: oil filter, air filter, cabin air filter, and fuel filter; 3. Three Fluids: windshield washer fluid, coolant, and battery fluid. The functions of engine oil are as follows: 1. Reduce friction and high temperatures; 2. Minimize gas leakage and prevent external contaminants; 3. Protect against contact between water, air, acidic harmful gases, and components; 4. Buffer the pressure rise in the engine cylinder port; 5. Clean dirt generated on the working surfaces of components.