GTX® DIESEL 15W40 Motor Oil, 5 L, JugBottle Provides exceptional protection from piston deposits, oil thickening and valve train wear while minimizing engine sludge formation Engineered to provide exceptional performance in engines operating under severe service conditions Including towing and hauling under high temperatures Special viscosity improvers, anti wear, anti oxidant and detergent additives protect and maintain cleanliness in hot running, heavy diesel and heavy duty gasoline