Which is quieter, 5w30 or 5w40 engine oil?

[Morgan]

Using 5w40 engine oil tends to be quieter than using 5w30 engine oil because 5w40 has a higher viscosity. Compared to 5w30, 5w40 engine oil has a higher high-temperature viscosity, providing better lubrication. Here is some relevant information about gasoline: 1. Introduction: Gasoline is a volatile, flammable hydrocarbon mixture liquid obtained from petroleum through distillation and cracking, used as fuel. It appears as a transparent liquid, is flammable, and has a distillation range of 30°C to 220°C. 2. Key characteristics: The important characteristics of gasoline include volatility, stability, anti-knock properties, corrosiveness, and cleanliness.

[MacJourney]

As a young driver who loves driving new cars, I pay special attention to engine noise levels because excessive noise can affect the driving mood. I've noticed that when using 5w30 oil, the car starts much quieter, especially on cold mornings when the engine starts up—it lubricates faster and reduces friction. In contrast, 5w40 has higher viscosity and flows slower at low temperatures, which might result in slightly more noise. However, this also depends on the car's condition: new car engines are designed for thinner oil, so 5w30 is a better match; older cars might need 5w40 to prevent increased noise, but overall, 5w30 offers a more noticeable quietness. I've also tried different brands, and fully synthetic oils like Shell's perform better. Remember to change the oil regularly, as degraded oil quality can also lead to increased noise.

[OAdriana]

With over 20 years of driving experience, I've tried both types of oil. 5W30 has better fluidity, making the engine sound smoother during startup and at low speeds—it's like a quiet old friend accompanying you. 5W40, with its higher viscosity, offers better protection at high speeds or temperatures, but the noise isn't necessarily less. I've also considered temperature effects: 5W30 performs better in winter, while 5W40 tends to have more noticeable noise fluctuations in summer. Ultimately, noise depends on the engine. Japanese cars generally suit 5W30 better with less noise, while German cars might need 5W40. Don't forget to check the oil level during maintenance—low oil levels will make any oil noisy. For long-term use, I prefer 5W30—it's cost-effective, comfortable, and reduces noise, making long drives less tiring.

[KevinLee]

From the perspective of oil quality, oil viscosity is the key factor affecting noise. 5W30 has lower viscosity in both winter and high temperatures, enabling quick engine lubrication and reducing friction noise, especially noticeable during cold starts. 5W40 has slightly higher high-temperature viscosity, which may offer more stability during high-speed driving, but the noise level usually remains the same or slightly increases. For new engines, 5W30 is the optimal choice; for older engines, 5W40 can help prevent abnormal noise, though this also depends on usage frequency. I recommend choosing a reliable full synthetic oil brand for better noise control.

[OCharles]

In my daily work at the auto shop, car owners often struggle with this issue. In most cases, 5w30 makes the engine quieter due to its lower viscosity and higher lubrication efficiency, which reduces metal friction noise. Especially during city driving with smooth acceleration, the noise is noticeably less. 5w40 is more suitable for performance cars or high-load engines, where the noise may be more consistent but not necessarily reduced. Checking oil quality is also crucial: inferior oil tends to be noisier regardless of the grade. The best solution is to follow the manual's recommended oil specifications, which usually resolves noise issues easily.