Antiwear Containing Lubricating Composition

Abstract

The present invention relates to a lubricating composition containing a sulphur-free metal salt of a hydrocarbyl-substituted phosphorus compound and an organo-sulphide. The composition has a sulphur content of greater than 0.3 weight percent of sulphur. The invention further provides for a method of lubricating a driveline device by using a lubricating composition.

1 . A lubricating composition comprising:
 (a) an oil of lubricating viscosity;   (b) a phosphorus containing additive comprising:
 (i) a sulphur-free metal salt of a hydrocarbyl-substituted phosphorus compound; and 
 (ii) optionally an ammonium or metal salt of a (thio)phosphoric acid ester different from (i); and 
   (c) an organo-sulphide, wherein the lubricating composition has a sulphur content of greater than 0.3 wt %.   
     
     
         2 . The lubricating composition of  claim 1 , wherein the lubricating composition has a sulphur content of about 0.5 wt % to about 5 wt %. 
     
     
         3 . The lubricating composition of  claim 1 , wherein the sulphur-free metal salt of a hydrocarbyl-substituted phosphorus compound comprises a metal salt of a hydrocarbyl-substituted phosphate, a metal salt of a hydrocarbyl-substituted phosphonate, a metal salt of a hydrocarbyl-substituted phosphinate, a metal salt of a hydrocarbyl-substituted phosphite, a metal salt of a hydrocarbyl-substituted phosphonite, a metal salt of a hydrocarbyl-substituted phosphinite, or mixtures thereof. 
     
     
         4 . The lubricating composition of  claim 3 , wherein the sulphur-free metal salt of a hydrocarbyl-substituted phosphorus compound comprises a metal salt of a hydrocarbyl-substituted phosphate, a metal salt of a hydrocarbyl-substituted phosphonate, a metal salt of a hydrocarbyl-substituted phosphonate, or mixtures thereof 
     
     
         5 . The lubricating composition of  claim 1 , wherein the sulphur-free metal salt of a hydrocarbyl-substituted phosphorus compound comprises a metal salt of a mono- or di-hydrocarbyl-substituted phosphate. 
     
     
         6 . The lubricating composition of  claim 1 , wherein the metal of the metal salt is selected from the group consisting of aluminium, calcium, magnesium, strontium, chromium, iron, cobalt, nickel, zinc, tin, lead, manganese, silver, and mixtures thereof. 
     
     
         7 . The lubricating composition of  claim 6 , wherein the metal of the metal salt is zinc. 
     
     
         8 . The lubricating composition of  claim 1 , further comprising an ammonium or metal salt of a (thio)phosphoric acid ester different from (i). 
     
     
         9 . The lubricating composition of  claim 1 , wherein the phosphorus containing additive comprises:
 (i) a metal salt of a sulphur-free hydrocarbyl-substituted phosphorus compound; and   (ii) an ammonium or metal salt of a phosphoric acid ester.   
     
     
         10 . The lubricating composition of  claim 1 , wherein the sulphur-free metal salt of a hydrocarbyl-substituted phosphorus compound is present in the lubricating composition in a range selected from the group consisting of about 0.001 wt % to about 10 wt %, and about 0.025 wt % to about 3 wt % of the lubricating composition. 
     
     
         11 . The lubricating composition of  claim 1 , wherein the organo-sulphide comprises a polysulphide, thiadiazole compound, or mixtures thereof. 
     
     
         12 . The lubricating composition of  claim 11 , wherein the organo-sulphide comprises a polysulphide. 
     
     
         13 . The lubricating composition of  claim 11 , wherein the organo-sulphide comprises a thiadiazole compound. 
     
     
         14 . The lubricating composition of  claim 1 , wherein the organo-sulphide is present in a range selected from the group consisting of about 0.01 wt % to about 10 wt, and about 0.25 wt % to about 6 wt % of the lubricating composition. 
     
     
         15 . The lubricating composition of  claim 1 , wherein the oil of lubricating viscosity comprises an API Group II, III, IV base oil, or mixtures thereof. 
     
     
         16 . A lubricating composition comprising:
 (a) an oil of lubricating viscosity;   (b) a phosphorus containing additive comprising:
 (i) a metal salt of a sulphur-free hydrocarbyl-substituted phosphorus compound; and 
 (ii) an ammonium or metal salt of a phosphoric acid ester; and 
   (c) an organo-sulphide, wherein the lubricating composition has a sulphur content in the range of greater than 0.3 wt %.   
     
     
         17 . A method of lubricating a driveline device, the method comprising supplying to the driveline device a lubricating composition comprising:
 (a) an oil of lubricating viscosity;   (b) a phosphorus containing additive comprising:
 (i) a sulphur-free metal salt of a hydrocarbyl-substituted phosphorus compound; and 
 (ii) optionally an ammonium or metal salt of a (thio)phosphoric acid ester different from (i); and 
   (c) an organo-sulphide, wherein the lubricating composition has a sulphur content of greater than 0.3 wt %.   
     
     
         18 . The method of  claim 17 , wherein the driveline device comprises a manual transmission or an axle gear. 
     
     
         19 . The use of the lubricating composition of  claim 1  in gears and transmissions to impart at least one of antiwear performance, extreme pressure performance, acceptable deposit control, acceptable oxidation stability and reduced odour.