Viscosity grades in Magnum diesel oils refer to the oil's thickness and its ability to flow at various temperatures, which is crucial for engine performance and protection. These oils are typically labeled with a two-part grade, such as 15W-40 or 5W-30, where the first number (e.g., 15W) represents the oil's viscosity in cold temperatures (the "W" stands for winter), ensuring easy sta... https://millenniumgroup.ae/understanding-viscosity-grades-in-magnum-diesel-oils/