Red Line's synthetic motor oils are designed to provide the highest protection, cleanliness and superior drain intervals with the lowest friction for your gasoline, diesel, motorcycle or marine engine. Red Line uses the most stable components available and formulate their products for wear protection and friction reduction across a wide range of engine operating conditions. Red Line's products are unique because they contain polyol ester base stocks, the only lubricants which can withstand the tremendous heat. The Red Line 0W40 is popular for European applications. Better flow at cold temps compared to 5w40 and 10w40.