| abstract |
The present invention relates to friction reducing agents for use in lubricating oil compositions comprising certain groups of aromatic compounds, esters, narrow mixtures of substrate raw materials, and / or amorphous polymers such as amorphous olefin copolymers. These compositions, when mixed with lubricating oil, can provide advantages such as substantial reduction of coefficient of friction and improved fuel economy without adverse effects such as instability, undesirable high viscosity and precipitation. In one aspect of the invention, pentaerythritol esters and optionally triol esters can be added to the lubricating oil composition to provide reduced friction and improved fuel economy. In a second aspect of the present invention, similar results can be obtained by adding hydrocarbyl aromatic to a lubricating oil composition containing one or more of Group II and Group III based raw materials. In a third aspect, the present invention relates to a lubricating oil composition comprising an amorphous olefin copolymer and at least one of Group II and Group III based raw materials. In one embodiment, the third aspect also includes one or more of the hydrocarbyl aromatic and polyol esters as part of the composition. In a fourth aspect, appropriate concentrations of hydrocarbyl aromatics are used in lubricating oil compositions comprising paraffin base oil and preferably polyisobutenyl succinimide borate ashless dispersant. |