What is the purpose of engine oil?

[ConnorFitz]

The purpose of engine oil is: 1. To reduce friction and high temperatures: A sufficiently thick oil film separates the surfaces of relatively sliding parts, thereby achieving the goal of reducing wear; 2. Sealing: Engine oil can form a sealing ring between the piston rings and pistons, reducing gas leakage and preventing external pollutants from entering; 3. Rust prevention: Lubricating oil can adhere to the surface of parts to prevent contact with water, air, acidic substances, and harmful gases; 4. Cushioning: When the pressure at the engine cylinder port rises sharply, suddenly increasing the load on the pistons, piston chips, connecting rods, and crankshaft bearings, this load is transmitted through bearing lubrication, cushioning the impact load; 5. Cleaning: Good engine oil can carry carbon deposits, sludge, and worn metal particles from engine parts back to the oil tank through circulation, and flush away dirt generated on the working surfaces of parts through the flow of the lubricating oil.

[OSawyer]

The main function of engine oil is to lubricate the moving parts inside the engine, such as pistons and crankshafts, reducing friction and wear between them. Otherwise, components can easily seize or get damaged. It also helps with heat dissipation—when the engine runs, it generates heat, and the oil acts like a coolant, carrying away heat to prevent overheating and cylinder seizure. Additionally, engine oil cleans the interior of the engine by absorbing dust and metal debris, preventing blockages and corrosion. For the engine as a whole, it helps seal gaps, maintaining compression efficiency and preventing leaks, thereby improving performance. I always check the oil level regularly and change it every 5,000 kilometers. This can extend the engine's lifespan by several years, save on major repair costs, and ensure smoother and safer driving. Don’t overlook this small detail—neglecting it could lead to serious failures.

[VanPreston]

As a stay-at-home dad, I shuttle my kids around every day, making engine oil's role particularly crucial. It ensures smooth engine operation, reduces vibrations and noise, and protects core components from premature wear. If the oil fails, the engine may suddenly overheat or stall, posing dangers during trips. I check the oil level monthly to ensure it remains clean and maintains proper lubrication, preventing unexpected breakdowns on the highway. This not only enhances safety but also saves money by reducing frequent repairs. Engine oil also improves fuel efficiency, cutting costs on long drives. As a responsible family man, I stick to simple maintenance to keep my car reliable.

[ClaireFitz]

Having driven for decades, engine oil is the lifeblood of an engine. It lubricates parts to prevent friction and overheating, and cleans dirt to extend lifespan. Change the oil more frequently, and your car can run for several more years.