5W30, 10W40, and 20W50

What Do 5W30, 10W40, and 20W50 Mean?

When you open the hood of your car or read through your vehicle’s maintenance manual, you will inevitably encounter a set of numbers and letters used to describe engine oil. Codes like 5W30, 10W40, and 20W50 often look like a complex mathematical formula to the average driver. However, understanding what these multi-grade ratings mean is…