Method for improving fuel economy of internal combustion engines using borated sulfur-containing 1,2-alkane diols

The lubricating oil composition formulated for use in the crankcase of an internal combustion engine in order to improve the fuel comsumption of said engine comprising

• (a) a major amount of an oil of lubricating viscosity;
• and
• (b) an effective amount of each of the following:
• 1. from 1%-20% of an ankenyl succinimide or alkenyl succinate or mixtures thereof,
• 2. from 0.1%-4% of a Group II metal salt of a dihydrocarbyl dithiophosphoric acid,
• 3. from 0.3%-10% of a neutral or overbased alkali or alkaline earth metal hydrocarbyl sulfonate or mixtures thereof,
• 4. from 0.3%-27% of a neutral or overbased alkali or alkaline earth metal alkylated phenate, or mixtures thereof, and
• 5. from 0.1%-5% of a borated sulfur-containing 1,2-alkane diol friction modifying agent of the formula:
• ##STR10## wherein R is alkyl containing from 5 to 30 carbon atoms, m is 1 or 2.