What is the correct weight classification for engine oil mentioned in the document?

The classification of engine oil is crucial as it indicates the oil's viscosity and performance characteristics under varying temperatures. The designation "15W-40LE" signifies that the oil has a viscosity rating of 15 in cold temperatures (the ‘W’ stands for winter) and a viscosity rating of 40 at operating temperatures. The "LE" part often indicates that the oil meets certain specifications for lower emissions, which is an important consideration for environmental standards and engine efficiency.

In engine oil classification, the first number refers to the oil's ability to flow at lower temperatures, which is essential for ensuring the engine starts smoothly in cold conditions. The second number reflects the oil's viscosity at high temperatures, ensuring it can maintain an adequate film between engine components even when they are hot and under stress. The chosen weight classification is relevant to the operating temperature ranges of the engine and helps in ensuring optimal performance and longevity.

Other classifications listed, while they belong to the same general category of multipurpose engine oils, suggest different performance characteristics, such as viscosity and suitability for specific operating conditions that may not match the requirements established in the document.