The "W" stands for Winter. This number indicates how well the oil flows at cold temperatures. A lower number (0W or 5W) means the oil stays thinner in the cold, helping your engine start more easily in winter.
The most common spec is the SAE (Society of Automotive Engineers) grade, like . engine oil specs.7z
Common in European cars (BMW, VW, Mercedes). Ratings like or C3 indicate specific requirements for high-performance engines or those with advanced exhaust filters. 3. Oil Types: Base Stocks The "W" stands for Winter
