Engine oil 3: Synthetic oil vs conventional oil
(引擎機油3：合成油及傳統油)
In our previous article we saw that modern synthetic oil is better than conventional oil because of its multigrade ability among other things. This allows the oil to change its viscosity nature instead of needing additives. Aside from that, what are their differences?
在我們之前的文章，我們看到現代的合成油因為它的複級特性優於傳統機油。這讓機油不需要添加劑而能自然的改變其黏度。除此之外，它們有甚麼樣的不同?
Conventional oil (傳統機油)
Also called regular or mineral-based, its base are hydrocarbons from petroleum. The popular thinking is that this is bad, but it does have its advantages.
也叫做一般或是礦物based機油，它們基本上是從石油中加輕裂解的。一般認為這油不好，但不過也有屬於它的優點。
The main advantage is obviously the price. It is not quite expensive because it derives from from abundant raw materials. As it is not created, the price reflects a lower cost.
主要的優點當然就是價格。由於是從原物料中分截取出來的，所以不貴。因為它不是被”創造”出來的，價格反映出低成本。
Also, thanks to the nature of the petroleum, it has a tendency to be monograde, which has lots of potential uses. This property forces the manufacturers to use additives to make these oils suitable for use at more extreme temperatures.
此外，要感謝石油的屬性，它具有一種單級的傾向，並且有許多應用潛力。這個特性迫使製造商使用添加劑好讓它在極端氣溫下能夠使用。
Other common reasoning is that conventional oil, since it has faster degradation, should be changed more regularly. This is both true and false at the same time. Although it has a faster degradation through oxidation, the same specifications and standards apply for both conventional and synthetic oil. So if a conventional oil meets a specification, it should last just as long as the a synthetic oil with the same specification. Therefore, the same cars can use both oils. If you want to read more about oil specifications, remember to check our article about them.
另一個原因是，因為傳統機油衰退的很快，所以要常常更換。這是事實卻也是錯誤的。傳統機油及合成機油在相同的規範及使用標準下，雖在氧化過程中會衰退很快。而如果傳統機油符合規範，它的耐久度應該跟規範相同的合成機油一樣。因此相同的車子這兩支油都可以使用。如果你想要了解更多關於機油的規範，請連結這篇文章。
This also means that the time interval to change the oil must be the same for both kind of oils. Always the amount of time or km the manufacturer recommends.
這也表示兩種機油的換油周期應該相同。通常都是依據車廠推薦的時間或公里數。
Synthetic oil (合成機油)
Besides its ability for naturally changing its viscosity depending on the temperature, synthetic oil has some other advantages.
除了它本身具備可依據溫度改變黏度的特性外，合成機油還有一些優點。
The most important one is that there is virtually no degradation with synthetic oil. This results in a healthier oil lifespan and also ensures the absence of deposits or sludge in the system. This translates into much greater protection against engine wear during its life cycle.
最重要的一點是合成油幾乎不會衰退。這表示能夠延長機油壽命，還能確定降低系統裡的沉積物或油泥。這也就是說在引擎運轉上具備較好的保護去能阻抗磨損。
Also, even when mineral-based oils contain additives to improve their viscosity index, synthetic oils still perform better at extreme temperatures. It has better natural protection against thermal breakdown and evaporation at higher temperatures, while retaining its fluidity in low-temperatures climates. That’s why lower temperatures oils like 0W20 or 5W30 are usually synthetic.
還有，雖然礦物性基礎油有添加劑能夠改善它們的黏度指數，合成油在極端氣溫的時候表現還是比較好。自身的高保護力能在高溫抵抗熱衰竭及蒸發，而在氣候低溫時仍保持其流動性。這也就是低溫機油如0W20 or 5W30，通常都使用合成油。
To sum up, synthetic oil: 總結論，合成機油：
- Performs better in extreme (higher or cooler) temperatures
在極端氣溫(很高溫或很低溫)表現較佳
- Keeps your engine cleaner from sludge or deposits, which can reduce power, performance or fuel economy
維持引擎清潔避免油泥或沉積物，因為這些都會讓動力、效能或燃油使用效率降低
- Offers greater protection against engine wear
提供引擎更好的保護抵抗磨損
Semi synthetic oil (半合成機油)
As the name suggests, semi synthetic oil is a blend of the two previous mentioned base oils. It is also known as hybrid oil.
就如名字所見，半合成機油是將之前的提到的2種基礎油混合。它也就是所說的” hybrid oil複合合成油”。
Semi synthetic oil incorporates the benefits of synthetic oils without the disadvantages of conventional oils. This means that it preserves its good behavior at extreme temperatures but it’s not that resilient. Usually higher grade oils like 10W50 or 15W40, event the best, are hybrid or conventional since with proper maintenance there is no real difference to using 100% synthetic oils.
半合成機油具備合成機油的優點卻沒有傳統機油的缺點。這表示在極端氣溫的時候它仍保有良好的屬性，但它沒有那麼有彈性。通常高黏度機油，例如10W50 或15W40，甚至更好的油(xenum產品連結)都是複合合成油或傳統油，在適當的維護下，跟使用100%合成油是沒有差別的。
The difference between semi and fully synthetic oil can also be noticeable in the price tag – the semi synthetic oil is generally a little bit cheaper.
半合成和全合成機油的不同也反映在價格上，半合成機油通常比較便宜一點點。
For a responsible owner who changes its oil when appropriate, the difference should be almost imperceptible in terms of security, performance at extreme temperatures or wear.
對一個會適時更換機油負有責任感的車主來說，在極度氣溫或磨損下的安全性及效能機乎是沒有差別的。