Abstract
Regulatory pressure is mounting where environmental preservation is concerned. Automotive manufacturers must reduce the fuel consumption of their models to meet future legislative requirements. Oil refiners have a role to play in this effort... one that is not confined to optimizing fuel formulations. The engine oil can be a source of substantial improvements or gains in fuel economy. In certain types of driving (notably city driving), fuel consumption can be reduced by up to 8%. The gain in fuel economy depends on the formulation of the engine oil. The choice of viscosity, base oils and additives is a compromise between engine power, price and wear. The experimental approach is means of demonstrating the influence of each of these factors on a standardised M111 FE test. In a 5W-30 oil that improves fuel economy by a total of 2.9% for example, the viscosity accounts for 2.2%, the choice of base oil 0.2% and the additivation 0.5%.