What does it feel like to switch from 40 to 30 engine oil?

[TaliaRose]

Switching back from 40 to 30 engine oil is completely fine, but the prerequisite is to purchase genuine oil from a reputable brand. Here are the specific details: 1. Vehicle model: If it's a low-end model that's seven or eight years old, it's still recommended to continue using 40 oil. After all, the engine wear is not in an upward phase, and the gap between the piston, piston rings, and cylinder walls has increased, requiring higher viscosity oil for protection. It is advisable to continue using 40 oil to achieve the effect of protecting the engine. 2. Engine: If the vehicle has a turbocharged (T) engine, due to its more precise construction and higher requirements for oil, it is recommended to use fully synthetic oil. For naturally aspirated engines, semi-synthetic oil can also meet the usage requirements. Different oils have different replacement cycles: semi-synthetic oil should be replaced every 7,500 kilometers or about 8 months, while fully synthetic oil, if used carefully, can be replaced every 10,000 kilometers or once a year.

[VanMarley]

As someone who commutes frequently in the city, I noticed that after switching from 40-weight to 30-weight oil, the car feels noticeably lighter overall. Cold starts in the morning are much quicker, no longer requiring long warm-up waits. Fuel consumption has significantly decreased, especially in traffic jams, saving 1-2 liters per 100 kilometers. Acceleration is smoother too, with much better take-off. The only downside is slightly increased engine noise at high speeds, and I worry about insufficient protection during long summer drives. So I recommend checking the owner's manual first to ensure compatibility and avoid engine damage.

[OValerie]

I've driven various cars for over a decade. After switching to 30-weight oil this time, I noticed the engine responds faster with immediate power delivery at light throttle. Fuel consumption has indeed decreased, especially noticeable during short commutes. However, the increased noise is a clear drawback, particularly more pronounced engine humming in older vehicles. Long-term, lower viscosity means weaker protection, potentially risky under high temperatures or RPMs. I recommend seasonal oil changes – using 30-weight in winter for better performance and switching back to 40-weight in summer to balance performance and protection.

[Lillian]

As a car enthusiast who pursues performance experience, I can feel the engine revs up faster after switching to 30-weight oil, with strong acceleration push during hard acceleration. The low viscosity makes power delivery more direct and drifting in corners smoother. However, be aware that oil temperature tends to rise in hot weather, and prolonged high-speed driving requires monitoring to avoid engine damage from insufficient oil pressure. Regular maintenance is essential.