abstract |
A method for improving wear control, while maintaining or improving fuel efficiency, in an engine or other mechanical component lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and (i) at least one transition metal salt of a carboxylic acid (e.g., zinc stearate) or (ii) a mixture of at least one transition metal salt of a carboxylic acid (e.g., zinc stearate) and at least one detergent (i.e., an alkali metal or alkaline earth metal salt of an organic acid, or an alkali metal or alkaline earth metal salt of an inorganic acid, or an alkali metal or alkaline earth metal salt of a phenol, or mixtures thereof (e.g., calcium salicylate and/or magnesium sulfonate)), as a minor component. The lubricating oils are useful in internal combustion engines. |