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Engine Oil

19/Jul/2023 277 |


The purpose of engine oil is to form a film of lubrication between all moving parts of an internal combustion engine to reduce friction and wear. Choosing the right engine oil for your vehicle and changing the oil during regularly-scheduled maintenance intervals will keep the engine running smoothly over time. The recommended oil type and specification for your vehicle can be found in the owner's manual. Another place to find it is on the oil fill cap. it will be based on the ambient temperature where you live. There are two engine oil codes that the owner’s manual will specify, an APl and an SAE.

API Code

All oil has an APl code which stands for American Petroleum Institute. it's a service rating for the quality, cleanliness, and types of detergents in the oil. The code will always be two letters.


The SAE is the viscosity or thickness of the oil. Modern oil is multi-viscosity oil. The SAE may be something to the effect of 5W-30. The first number-letter combo (5W) indicates the viscosity or thickness of the oil when it is cold. The second number is the viscosity at the engine operating temperature. Before they had multi-viscosity oil there was only single-viscosity oil (such as SAE 30), which in cold weather was extremely thick. Trying to pour it into your engine would be like pouring honey, but more importantly, it would be hard to pump the oil and lubricate the engine. That's why older engines had to be warmed up before you could drive them.

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