| abstract |
A method for improving fuel efficiency and friction reduction properties, while maintaining or improving deposit control, in an engine 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 a tungsten organic complex as a minor component. Fuel efficiency and friction reduction properties are improved and deposit control is maintained or improved as compared to friction reduction properties and deposit control achieved using a lubricating engine oil containing a minor component other than the tungsten organic complex. A lubricating engine oil having a composition comprising a lubricating oil base stock as a major component, and a tungsten organic complex as a minor component. The lubricating engine oils are useful in internal combustion engines including direct injection, gasoline and diesel engines. |