abstract |
A lubricating oil composition is disclosed which comprises (a) a major amount of an oil of lubricating viscosity, (b) one or more phosphorus-containing anti-wear additives other than a zinc dithiophosphate, (c) one or more ashless dispersants, (d) one or more metal-containing detergents, and (e) one or more antioxidants, wherein the lubricating oil composition contains no more than about 0.03 weight percent of phosphorus, based on the total weight of the natural gas engine lubricating oil composition, and further wherein the lubricating oil composition is substantially free of any zinc compounds. |