Lubricant composition promoting sustained fuel economy

Abstract

A lubricant composition includes a controlled release friction modifier (CRFM), a highly paraffinic base stock, a dispersant and a detergent. The CRFM includes an ionic tetrahedral borate compound including a cation and a tetrahedral borate anion, wherein the tetrahedral borate anion comprises a boron atom having two bidentate di-oxo ligands of C18 tartrimide. The lubricant composition can also include at least one of a Group V co-base stock, an inorganic friction modifier, a viscosity modifier, and a cleanliness booster.

What is claimed is: 
     
         1 . A lubricant composition, comprising:
 a controlled release friction modifier (CRFM); including:
 a tetrahedral borate anion having a boron atom with two bidentate di-oxo ligands both being a linear C 18 -tartrimide; 
 a first dispersant comprising a conventional ammonium substituted polyisobutenyl succinimide compound having a polyisobutenyl number average molecular weight of 750 to 2,500; 
 a second dispersant comprising an ammonium substituted polyisobutenyl succinimide compound having an N:CO ratio of 1.8 and a polyisobutylenyl number average molecular weight of 750 to 2,500; 
   a highly paraffinic base stock selected from the group consisting of at least one Group III base stock, at least one Group IV polyalphaolefin (PAO) base stock and combinations thereof;   a third dispersant; and   a detergent.   
     
     
         2 . The lubricant composition of  claim 1 , further comprising at least one of a Group V co-base stock, an inorganic friction modifier, a viscosity modifier, and a cleanliness booster. 
     
     
         3 . The lubricant composition of  claim 1 , wherein the third dispersant is selected from the group consisting of succinimide, polyolefin amide alkeneamine, ethylene capped succinimide, borated polyisobutylsuccinimide-polyamine, and mixtures thereof. 
     
     
         4 . The lubricant composition of  claim 1 , wherein the detergent is selected from the group consisting of highly overbased calcium salicylate, low base calcium salicylate and overbased magnesium sulfonate, neutral calcium sulfonate and mixtures thereof. 
     
     
         5 . The lubricant composition of  claim 3 , wherein the Group V co-base stock is selected from the group consisting of esters, alkylated naphthalenes and mixtures thereof. 
     
     
         6 . The lubricant composition of  claim 1 , wherein the PAO base stock comprises up to 60 wt % of the composition. 
     
     
         7 . The lubricant composition of  claim 1 , wherein the Group III base stock comprises 10-90 wt % of the composition. 
     
     
         8 . The lubricant composition of  claim 1 , wherein the third dispersant comprises 1-12 wt % of the composition. 
     
     
         9 . The lubricant composition of  claim 1 , wherein the detergent comprises 1-8 wt % of the composition. 
     
     
         10 . The lubricant composition of  claim 1 , wherein the CRFM comprises 2-8 wt % of the composition. 
     
     
         11 . A lubricant composition, comprising:
 a controlled release friction modifier (CRFM) including:
 a tetrahedral borate anion having a boron atom with two bidentate di-oxo ligands both being a linear C 18 -tartrimide; 
 a first dispersant comprising a conventional ammonium substituted polyisobutenyl succinimide compound having a polyisobutenyl number average molecular weight of 750 to 2,500; 
 a second dispersant comprising an ammonium substituted polyisobutenyl succinimide compound having an N:CO ratio of 1.8 and a polyisobutylenyl number average molecular weight of 750 to 2,500; 
   a highly paraffinic base stock selected from the group consisting of at least one Group III base stock, at least one Group IV polyalphaolefin (PAO) base stock or combinations thereof;   a third dispersant selected from the group consisting of succinimide, polyolefin amide alkeneamine, ethylene capped succinimide, borated polyisobutylsuccinimide-polyamine and mixtures thereof; and   a detergent selected from the group consisting of highly overbased calcium salicylate, low base calcium salicylate and overbased magnesium sulfonate, neutral calcium sulfonate and mixtures thereof.   
     
     
         12 . The lubricant composition of  claim 11 , further comprising at least one of a Group V co-base stock, an inorganic friction modifier, a viscosity modifier, and a cleanliness booster. 
     
     
         13 . The lubricant composition of  claim 12 , wherein the Group V co-base stock is selected from the group consisting of esters, alkylated naphthalenes and mixtures thereof. 
     
     
         14 . The lubricant composition of  claim 11 , wherein the PAO base stock comprises up to 60 wt % of the composition. 
     
     
         15 . The lubricant composition of  claim 11 , wherein the Group III base stock comprises 10-90 wt % of the composition. 
     
     
         16 . The lubricant composition of  claim 11 , wherein the third dispersant comprises 1-12 wt % of the composition. 
     
     
         17 . The lubricant composition of  claim 11 , wherein the detergent comprises 1-8 wt % of the composition. 
     
     
         18 . The lubricant composition of  claim 11 , wherein the CRFM comprises 2-8 wt % of the composition. 
     
     
         19 . A lubricant composition, comprising:
 a controlled release friction modifier (CRFM) comprising 3.96 wt % of the composition, the CRFM including:
 a tetrahedral borate anion having a boron atom with two bidentate di-oxo ligands both being a linear C 18 -tartrimide; 
 a first dispersant comprising a conventional ammonium substituted polyisobutenyl succinimide compound having a polyisobutenyl number average molecular weight of 750 to 2,500; 
 a second dispersant comprising an ammonium substituted polyisobutenyl succinimide compound having an N:CO ratio of 1.8 and a polyisobutylenyl number average molecular weight of 750 to 2,500; 
   a highly paraffinic base stock comprising at least one Group III base stock, at least one Group IV polyalphaolefin (PAO) base stock, wherein the PAO base stock comprises 10-31.92 wt % of the composition and the Group III base stock comprises 40-64.21 wt % of the composition;   a third dispersant, wherein the dispersant comprises 4.44-5.4 wt % of the composition; and   a detergent, wherein the detergent comprises 2.03-3.83 wt % of the composition.