What is SL5W30 engine oil?
1 Answers
Shell SL5W-30 is a multi-grade oil specification, and the specific parameters mean: 1. S: SAE viscosity grade standard; 2. L: API certification, where L represents automotive engine oil, with letters further in the alphabet indicating higher oil quality; 3. 0: Oil's low-temperature fluidity, where a smaller number indicates better low-temperature fluidity and a lower usable environmental temperature; 5W corresponds to an external temperature of -35 degrees Celsius; 4. W: Winter; 5. 30: Viscosity at high temperatures, where a higher number indicates greater oil viscosity and a higher usable environmental temperature. Additional information: 1. Viscosity specification: The grade following the oil classification indicates its viscosity specification. For example, in "15W-40, 5W-40," "W" stands for Winter, and the smaller the number before it, the better the oil's low-temperature fluidity, representing a lower usable environmental temperature and better engine protection during cold starts. For instance, 5W represents resistance to external temperatures as low as -30°C, while 20W is resistant to -15°C. 2. Kinematic viscosity: The number after W represents the oil's kinematic viscosity at 100°C, with higher numbers indicating higher viscosity. 40 means the kinematic viscosity standard at 100 degrees Celsius is between 12.5mm2/s and 16.3mm2/s, and it definitely does not mean it can be used below 40°C as some rumors suggest.
