Which is better, semi-synthetic or full synthetic engine oil?

[Hank]

Full synthetic engine oil performs better in terms of performance. The differences between the two and the advantages of full synthetic engine oil are as follows: Differences between the two: Semi-synthetic and full synthetic engine oils are two classifications of engine oil. The biggest difference between them is that full synthetic oil can be used over a wider temperature range and has a longer service life. For the same oil film requirements, full synthetic oil can achieve the desired performance with a lower viscosity, while semi-synthetic oil requires a relatively higher viscosity to meet the same requirements. In other words, under the same working conditions, full synthetic oil can protect the engine with a lower viscosity. Advantages of full synthetic engine oil: Full synthetic engine oil has better high and low temperature performance, a longer oil change interval, and is suitable for more severe driving conditions. It outperforms semi-synthetic oil in engine protection, oxidation resistance, and low-temperature starting performance.

[ZacharyFitz]

I believe fully synthetic oil has performance advantages. It maintains stable viscosity under both high and low temperatures, providing more comprehensive protection for engine components and extending service life. It's suitable for those who frequently drive long distances or engage in aggressive driving. Although it's more expensive, reduced wear means saving money in the long run. Semi-synthetic oil is more affordable and suitable for daily commuting, but it may degrade faster in summer heat. Choose based on your budget and habits, and don't neglect regular maintenance.

[LiamLynn]

From an economic perspective, semi-synthetic oil is quite cost-effective. It's cheaper with shorter change intervals, saving money while being reliable. I've been using full synthetic oil for years. Although it's slightly more expensive, it allows me to drive thousands of kilometers more before changing, saving time and money in the long run. I recommend full synthetic for new cars or high-mileage vehicles, while semi-synthetic is sufficient for regular cars—no need to waste money on premium options. Driving habits are what really matter.

[LaAnthony]

I've tried two types of oil in my regular sedan. Semi-synthetic oil works fine for daily use, but after switching to full synthetic, the engine starts more smoothly, doesn't hesitate in winter, and runs quieter and more stable. The improvement is quite noticeable, though semi-synthetic is perfectly adequate for simple commuting.