Low viscosity lubricating oil

Abstract

A lubricating oil composition for internal combustion engine with a roller follower type valvetrain is disclosed. The composition includes major amount of an oil of lubricating viscosity; one or more magnesium detergents in an amount to provide 100 to 1000 ppm of magnesium to the lubricating oil composition; 0.1 to 0.5 wt % of organic friction modifier; and d) optionally a viscosity modifier present at no more 0.5 wt %. The composition is substantially free of molybdenum friction modifier and has a total boron content ranging from 20 to 200 ppm.

1 . A lubricating oil composition for internal combustion engine with a roller follower type valvetrain, comprising:
 a) major amount of an oil of lubricating viscosity;   b) one or more magnesium detergents in an amount to provide 100 to 1000 ppm of magnesium to the lubricating oil composition;   c) 0.1 to 0.5 wt % of organic friction modifier; and   d) optionally a viscosity modifier present at no more 0.5 wt % wherein the lubricating oil composition is substantially free of molybdenum friction modifier and has a total boron content ranging from 20 to 200 ppm.   
     
     
         2 . The lubricating oil composition of  claim 1 , wherein the oil of lubricating viscosity is a group III base oil having a kinematic viscosity at 100° C. ranging from 4 cSt to 4.5 cSt. 
     
     
         3 . The lubricating oil composition of  claim 1 , where the organic friction modifier is glycerol monooleate or borated glycerol monooleate. 
     
     
         4 . The lubricating oil composition of  claim 2 , wherein the viscosity modifier is a non-dispersant comb polymethacrylate, linear polymethacrylate, olefin copolymer, or hydrogenated styrene-diene type copolymer. 
     
     
         5 . The lubricating oil composition of  claim 1 , further comprising a dispersant. 
     
     
         6 . The lubricating oil composition of  claim 5 , wherein the dispersant is borated or non-borated. 
     
     
         7 . The lubricating oil composition of  claim 5 , wherein the dispersant is a succinimide dispersant. 
     
     
         8 . A method of improving fuel efficiency of an internal combustion engine, wherein the method comprises:
 lubricating the internal combustion engine with a lubricating oil composition comprising:   a) major amount of an oil of lubricating viscosity;   b) one or more magnesium detergent in an amount to provide 100 to 1000 ppm of magnesium to the lubricating oil composition;   c) 0.1 to 0.5 wt % of organic friction modifier; and   d) optionally a viscosity modifier present at no more 0.5 wt %;   wherein the lubricating oil composition is substantially free of molybdenum friction modifier and has a total boron content ranging from 20 to 200 ppm.   
     
     
         9 . The method of  claim 8 , wherein the oil of lubricating viscosity is a group III base oil having a kinematic viscosity at 100° C. ranging from 4 cSt to 4.5 cSt. 
     
     
         10 . The method of  claim 8 , where the organic friction modifier is glycerol monooleate or borated glycerol monooleate. 
     
     
         11 . The method of  claim 8 , wherein the viscosity modifier is a non-dispersant comb polymethacrylate, linear polymethacrylate, olefin copolymer, or hydrogenated styrene-diene type copolymer. 
     
     
         12 . The method of  claim 8  wherein the internal combustion engine includes roller follower type valvetrain. 
     
     
         13 . The method of  claim 8 , wherein the lubricating oil composition further comprises a dispersant. 
     
     
         14 . The method of  claim 13 , wherein the dispersant is borated or non-borated. 
     
     
         15 . The method of  claim 13 , wherein the dispersant is a succinimide dispersant.