In a few words:
The best type of engine oil that you can use is the synthetic one. You will find the rest of specifications such as viscosity and quality in the owner's manual of your Eos.
Viscosity is a measure of an oil’s resistance to flow: The thicker (higher viscosity) the oil, the slower it will flow and it will take more time to reach every part of the engine. It is commonly said that the oil is "heavier" when it is more viscous and "lighter" in the opposite case. Viscosity grades are measured based on SAE standards.
We advise you to look for the recommended viscosity in your owner's manual or ask your trusted mechanic. If you can’t find the information and you have to change the engine oil, this is what you have to know:
When engines work at low temperatures (engine start), the oil should be more fluid in order to reach every part of the engine and ensure immediate lubrication. After a few minutes, the temperature of the engine will rise and, ideally, the oil viscosity should be higher. This ensures proper lubrication without breaking the lubricant film. Nowadays, all oils meet this requirement and they are called multigrade oils (lower viscosity at cold temperatures and higher viscosity at hot temperatures).
A medium viscosity level would be the SAE 10W-40 engine oil, which meet the needs of the current car models without difficulty.
If you live in a place where the temperature drops to 14° F (-10° C) or less you should use an oil with lower viscosity (5W-40 for example).
⚠️ If your vehicle has over 124,000 mi and consumes oil or you see some white smoke coming from the exhaust pipe, you can use an oil with a slightly higher viscosity to compensate for wear.
You can find the specific engine oil quality for your Eos in the Maintenance section of your owner's manual. If you can’t find it there, keep in mind the following:
Lubricants are classified by the American Petroleum Institute (API) based on their performance level. You will find listed below the current standards for gasoline engines. To find out which lubricant does your Eos need, you just have to choose the option that coincides with the year of manufacture of your car.
The following are the emission standards that Diesel engines must meet according to the year of manufacture and the amount of sulfur in the fuel:
The API classification can be easily found on the oil bottle label. Here you can see it:
There are 3 types of engine oil, 2 of them are basic and the third one is a blend of both:
⚠️ General recommendations if you’re thinking of changing the engine oil of your Eos
– Use oils of well-known brands. These are not necessarily more expensive and you will definitely get better results.
– You should never use synthetic oil in a car that has been using mineral oil. It will remove all the dirt abruptly and block the oil lines and filters. If you want to make this change, you will first have to use a semi synthetic oil and see what happens. Ideally, the oil will gradually remove the engine dirt.