DELO SILVER (20W-50)-4L is a reliable heavy-duty diesel engine oil designed for engines requiring API CF-4, CF, or SG performance. Its proven anti-wear additives form a protective layer to minimize wear, while metallic detergents and dispersants prevent deposits, sludge, and oil thickening. With strong oxidation stability and deposit control, it preserves power and extends engine life—ideal for mixed diesel and gasoline fleets, high-speed engines, and commercial transport operations.