What is the main purpose of engine oil?

The main purpose of engine oil is to lubricate moving parts within the engine. This lubrication creates a protective film that reduces friction between engine components, such as pistons, crankshafts, and camshafts. By minimizing friction, engine oil helps to prevent wear and tear, thereby extending the life of the engine and enhancing its performance.

Good lubrication is critical because without it, metal parts would grind against each other, leading to increased heat and potential engine damage. Additionally, engine oil assists in the dispersal of heat away from moving parts, although its primary role is lubrication. Proper oil also helps in cleaning the engine by suspending contaminants and preventing deposits from forming.

While engine oil can contribute to noise reduction by providing a cushioning effect and reducing friction, and it plays a role in cooling by transferring some heat away from the engine, those factors are secondary to its primary function, which is lubrication. Transferring fuel is not a function of engine oil; that process is entirely separate and involves the fuel system of the engine.