Transmission Lubricant Composition

Abstract

A lubricant composition comprising a) a synthetic poly-alpha-olefin base fluid; b) an organomolybdenum friction modifier; c) an alkylphosphorothiolate and a hydrocarbylamine anti-wear combination; and d) a dihydrocarbyl dithiophosphate extreme pressure additive and optionally one or more of e) a copper corrosion inhibitor; f) an anti-foam agent; g) a solubilizing agent; h) polymeric viscosity index improver; and i) an oligomeric viscosity modifier is highly suitable for use in the synchronizer of a transmission.

1 . A lubricant composition comprising
 a) a synthetic poly-alpha-olefin base fluid;   b) an organomolybdenum friction modifier;   c) an alkylphosphorothiolate and a hydrocarbylamine anti-wear combination; and   d) a dihydrocarbyl dithiophosphate extreme pressure additive.   
     
     
         2 . The lubricant composition according to  claim 1  comprising a synthetic poly-alpha-olefin base fluid selected from the group consisting of about C 8  to about C 16  poly-alpha-olefins. 
     
     
         3 . (canceled) 
     
     
         4 . The lubricant composition according to  claim 1  comprising a friction modifier selected from the group consisting of organomolybdenum dithiocarbamates, organomolybdenum dithiophosphates, molybdenum carboxylate salts, molybdenum-amine complexes, molybdenum amine/alcohol/amide complexes, molybdenum cluster compounds and molybdenum disulfide. 
     
     
         5 . (canceled) 
     
     
         6 . The lubricant composition according to  claim 1  comprising an alkylphosphorothiolate of formula 
       
         
           
           
               
               
           
         
       
       wherein 
       R 1 , R 2  and R 3  are each independently hydrocarbyl or hydrogen, wherein at least one of R 1 , R 2  and R 3  are hydrocarbyl and 
       X 1 , X 2  and X 3  are independently oxygen or sulfur. 
     
     
         7 . The lubricant composition according to  claim 1  comprising a hydrocarbylamine selected from the group consisting of alkylene diamines, primary hydrocarbylamines, and a combination thereof. 
     
     
         8 . (canceled) 
     
     
         9 . The lubricant composition according to  claim 1 , wherein the wt/wt ratio of the alkylphosphorothiolate and hydrocarbylamine is from about 1/9 to about 9/1. 
     
     
         10 . The lubricant composition according to  claim 1  comprising a dihydrocarbyl dithiophosphate of formula 
       
         
           
           
               
               
           
         
       
       wherein 
       R 4 , R 5  and R 6  are each independently hydrocarbyl. 
     
     
         11 . (canceled) 
     
     
         12 . The lubricant composition according to  claim 1  having a kinematic viscosity of from about 9.0 mm 2 /s to about 15.0 mm 2 /s at 100° C., determined according to ASTM D445. 
     
     
         13 . The lubricant composition according to  claim 1  wherein the synthetic base fluid is from about 62 wt % (weight percent to about 88 wt %, based on the weight of the total composition. 
     
     
         14 . The lubricant composition according to  claim 1  wherein the organomolybdenum friction modifier is from about 0.2 wt % to about 1.0 wt %, based on the total weight of the composition. 
     
     
         15 . The lubricant composition according to claim wherein the anti-wear combination is from about 0.2 wt % to about 1.0 wt %, based on the total weight of the composition. 
     
     
         16 . The lubricant composition according to claim wherein the dihydrocarbyl dithiophosphate extreme pressure additive is from about 0.2 to about 1.2 wt %, based on the total weight of the composition. 
     
     
         17 . (canceled) 
     
     
         18 . The lubricant composition according to  claim 1  further comprising:
 a copper corrosion inhibitor from about 0.10 wt % to about 0.60 wt %, based on the total weight of the composition, 
 an anti-foam agent from about 0.10 wt % to about 1.20 wt %, based on the total weight of the lubricant composition, 
 a solubilizing agent from about 1.0 wt % to about 9.0 wt %, based on the total weight of the lubricant composition, 
 a polymeric viscosity index improver from about 1.0 wt % to about 9.0 wt %, based on the total weight of the lubricant composition, 
 an oligomeric viscosity modifier from about 1.0 wt % to about 9.0 wt %, based on the total weight of the lubricant composition, and 
 a further component selected from the group consisting of solvents, hindered phenolic antioxidants, aminic antioxidants, metal passivators, rust inhibitors, pour point depressants, dispersants, further anti-foam agents, demulsifiers, further friction modifiers, further anti-wear additives, detergents and mixtures thereof. 
 
     
     
         19 .- 36 . (canceled) 
     
     
         37 . A lubricant composition comprising
 ) a synthetic poly-alpha-olefin base fluid;   b) an organomolybdenum friction modifier;   c) an alkylphosphorothiolate and hydrocarbylamine anti-wear additive combination;   d) a dihydrocarbyl dithiophosphate extreme pressure additive; and   e) a copper corrosion inhibitor; and/or   f) an anti-foam agent; and/or   g) a solubilizing agent; and/or   h) a polymeric viscosity index improver; and/or   i) an oligomeric viscosity modifier; and/or   j) a further component.   
     
     
         38 .- 40 . (canceled) 
     
     
         41 . A method of lubricating a surface in the synchronizer of a transmission, the method comprising supplying thereto a lubricant composition according to  claim 1 . 
     
     
         42 . A method according to  claim 41 , wherein the synchronizer comprises a surface selected from the group consisting of molybdenum, bronze, brass, iron, carbon and steel. 
     
     
         43 . A transmission comprising the lubricant composition according to  claim 1 . 
     
     
         44 . A gear box comprising the lubricant composition according to  claim 1 . 
     
     
         45 . A vehicle comprising the lubricant composition according to  claim 1 . 
     
     
         46 . A vehicle comprising a transmission comprising the lubricant composition according to  claim 1 .