Improving fuel economy without compromising wear and oxidative viscosity control in ultra-low viscosity engine oils

The automotive industry is continuously looking to improve fuel economy in order to meet stringent government regulations around carbon emissions reduction. To achieve fuel economy targets, OEMs have explored lowering the viscosity of the engine oil to reduces energy losses. Many OEMs are currently designing engines that operate with 0W-20 viscosity engine oil and lower. Recently, ultra-low viscosity engine oil categories, such as JASO GLV-1, have been developed to further improve fuel economy through fluid design (reduction of friction of the engine oil). However, as the viscosity of the fluid is reduced, the fluid’s ability to control viscosity and wear is often also reduced. This paper details a holistic formulation approach to deliver improved fuel economy without compromising wear and oxidative viscosity control. Advanced fuel economy studies were conducted which combined simulated fuel economy modelling with a fired engine fuel economy test to provide fluid formulations with significant fuel economy improvement. In parallel, a series of studies in wear and oxidative viscosity control tests have identified pathways to deliver optimal performance without degrading the fuel economy improvement. The resultant formulations provide improved fuel economy without compromising wear and oxidative viscosity control as measured in the emerging global industry standard tests.