What does 10w-40 mean for engine oil?
1 Answers
10w-40 refers to the SAE standard viscosity value of the engine oil. Here are the relevant explanations: 1. The number after W represents the kinematic viscosity of the oil at 100℃. The higher the number, the higher the viscosity. 2. The oil grade includes two parts: classification and viscosity specification. The oil grade usually indicates viscosity and quality. 3. W stands for winter. The smaller the number before it, the better the low-temperature fluidity of the oil, indicating a lower usable environmental temperature and better protection for the engine during cold starts. The number after "W" (after the hyphen) is an indicator of the oil's high-temperature resistance. The larger the number, the better the oil's protective performance at high temperatures.