A lubricating oil composition comprises an amide and at least one additive. A lubricating grease composition comprises a liquid amide, a thickener comprising a metal soap, and at least one additive. The amide in each composition is the reaction product of a secondary, branched amine and a carboxylic acid. The carboxylic acid may be a monocarboxylic acid or a dicarboxylic acid, including dimer acid. The amide is hydrolytically stable, and may be used to increase the hydrolytic stability of the lubricant oil or grease composition. Alternatively, the amide may be used to increase the additive solubility or detergency of the lubricant oil or grease composition.