摘要 |
<p>The present invention is directed to a method for improving the fuel efficiency of large low and medium speed engine oil compositions by reducing the traction coefficient of the oil by formulating the oil using a blend consisting of one or more Group I base oils having a kinematic viscosity at 100°C of from 2 to less than 12 mm2/s in combination with a Group IV base oil having a kinematic viscosity of at least 38, the difference in kinematic viscosity between the Group I and Group IV oils in the blend being at least 30 mm2/s in combination with a detergent.</p> |