The present invention is directed to a low sulfur and low phosphorus heavy duty diesel engine lubricating oil composition comprising (a) a major amount of an oil of lubricating viscosity and (b) one or more dispersants (c) one or more anti-oxidants and (d) one or more ash-containing detergents, wherein the lubricating oil composition is essentially free of zinc di-alkyl di-thiophosphates and contains no more than 0.175 weight percent sulfur and provided the lubricating oil composition does not contain alkylated and non-alkylated aromatic amines and tri-nuclear molybdenum compounds. The present invention is also directed to a low sulfur and low phosphorus heavy duty diesel engine lubricating oil composition comprising (a) an oil of lubricating viscosity (b) a borated dispersant and a non-borated dispersant (c) a molybdenum anti-oxidant and a phenolic anti-oxidant and (d) a low overbased calcium sulfonate and a high overbased calcium phenate, wherein the lubricating oil composition is essentially free of zinc di-alkyl di-thiophosphates and contains no more than 0.175 weight percent sulfur and provided the lubricating oil composition does not contain alkylated and non-alkylated aromatic amines and tri-nuclear molybdenum compounds. The present invention is also directed to method for lubricating a heavy duty diesel engines, which comprises lubricating the engine with a low sulfur and low phosphorus heavy duty diesel engine lubricating oil compositions of the present invention.