Champion's Low-Ash 15w-40 Full Synthetic CNG Engine Oil comes specifically designed to be used with vehicles powered by CNG, LNG oand propane autogas. The 15w-40 multi-grade viscosity has reduced ash content and offers superior valve recession protection, low oil consumption, piston deposit control, good TBN retention, shear stability, enhanced valve train wear protection, excellent cold start protection, advanced oxidation control, long life and low exhaust emissions; according to the company. The product can be purchased in 5-gallon pails, 55-gallon drums and 330-gallon totes.