What is the purpose of car engine oil?

[VonAvery]

Car engine oil serves the following purposes: 1. It separates the relatively sliding surfaces of parts to reduce wear; 2. It carries heat back to the oil tank and then dissipates it into the air, assisting the radiator in cooling the engine; 3. It circulates carbon deposits, sludge, and worn metal particles from engine parts back to the oil tank, flushing away dirt generated on the working surfaces of parts through the flow of the lubricating oil. The meaning of engine oil grades is: 1. The letter 'w' stands for winter, indicating all-season oil; 2. The number before 'w' represents the viscosity of the oil under low-temperature conditions, with a smaller number indicating better low-temperature fluidity; 3. The number after 'w' represents the standard for kinematic viscosity at 100 degrees Celsius, categorized into 20, 30, 40, 50, and 60, with the viscosity standard affecting the oil's adhesion performance at high temperatures.

[Walter]

Speaking of engine oil, as a car enthusiast, I have to talk about its wonders. Simply put, engine oil is like the engine's versatile little helper, mainly focusing on lubrication: it gets into small corners like pistons and crankshafts, making metal parts slide smoothly without getting stuck and creaking. The cleaning function is also quite important—additives in the oil can sweep away residue and dust from combustion, which can clog things up if they accumulate too much. There's also the cooling function; the engine gets really hot, and the circulating oil carries away the high heat. It seals gaps to prevent gas leaks, inevitably extending the engine's lifespan. Don’t forget rust prevention—it isolates air and moisture, keeping the engine from rusting and aging. The key takeaway is regular oil changes. I recommend checking every 5,000 or 10,000 kilometers, choosing the right viscosity to avoid engine burning or skyrocketing fuel consumption. Long-term use of low-quality oil will wear out parts, leading to repair costs in the thousands or even tens of thousands—totally not worth it. Remember, with stable engine oil, your car runs longer and stays quiet even at high speeds.

[DeBeau]

In my experience of repairing hundreds of vehicles, the core function of engine oil is to maintain engine health. Its primary task is lubrication, reducing friction between internal components to prevent wear – absolutely critical. Secondly, it cools the engine by circulating and absorbing high temperatures; otherwise, overheating and cylinder scoring issues arise. Additionally, its role in cleaning impurities cannot be overlooked – it collects dust and carbon deposits to avoid clogging the filtration system. The sealing and anti-rust properties are also noteworthy, as oil fills gaps and adds protective layers, extending lifespan while saving hassle and money. Accordingly, I always remind car owners to regularly check oil levels and quality, not waiting for warning lights. Synthetic oil outperforms mineral oil in durability and efficiency – always match viscosity grade when selecting oil. Neglecting maintenance may lead to soaring fuel consumption or starting difficulties. Regular oil changes ensure safety and reliability, giving drivers greater peace of mind on the road.

[DiBentley]

Having driven for decades, I see that engine oil is directly related to family safety and the wallet. Lubrication keeps the engine running smoothly—if it seizes up, the repair costs can be staggering. The cooling function prevents overheating, which is especially crucial during long summer trips. The cleaning effect protects the engine internals, reducing issues. Sealing and rust prevention are bonuses, extending the machine's lifespan. Accordingly, I recommend everyone change the oil regularly—don’t slack off beyond 5,000 kilometers, or the check engine light will cost you unnecessary expenses. Poor-quality oil makes the car sluggish and wastes fuel, while proper maintenance ensures peace of mind and safety, letting you travel worry-free.