What is the definition of SAE?

[Shelly]

SAE is the abbreviation for the Society of Automotive Engineers in the United States, referring to the viscosity grade classification of gear oil. The following is relevant information about SAE: 1. Classification: Gear oil can be divided into single-grade viscosity type and multi-grade viscosity all-weather type. The single-grade viscosity type can be further divided into high-temperature type and low-temperature type. 2. Meaning: The high-temperature type is labeled similarly to SAE90, SAE140, etc. The number following SAE indicates the viscosity of the oil at 100°C, with a larger number indicating higher oil viscosity. The low-temperature type is labeled similarly to SAE75W, where W stands for winter (low-temperature type), 75 represents viscosity, and a smaller number indicates better low-temperature performance.