Low viscosity lubricating oil compsns - contg mineral and synthetic oils, giving reduced oil consumption

摘要

Motor oils of 10 W/20 to 5W/20 viscosity grades consist of a refined mineral oil of viscosity index 80-105 and viscosity at 100 degrees C. of 7.5-12 cSt. and 10-30% of oil-soluble synthetic oil of viscosity at 100 degrees C. of 3-5 cSt. Both oils have volatility by the Noack (DIN 51581) test of 3-10%. The synthetic oil is pref. a diester. Although both oils are of similar volatility, the mixt. shows a lower oil consumption rate than the mineral oil alone.