Doc's Diesel SAE 15W-40 Full Synthetic Heavy Duty Engine Oil is a high-quality motor oil designed specifically for diesel engines. This 1-gallon jug of oil is made in the United States and is formulated to provide superior protection and performance for heavy-duty engines. With a viscosity of 15W-40, this oil offers excellent lubrication and protection against wear and tear. Perfect for truck fleets, construction equipment, and other heavy-duty vehicles, Doc's Diesel engine oil is a reliable choice for maintaining the health and longevity of your engine. Free shipping in the lower 48 United States. Shipping to Alaska, Hawaii, or Puerto Rico will cost additional. I do not offer shipping outside of the United States.