Boron free automotive gear oil

Abstract

The present disclosure provides a method for lubricating a gear or transmission comprising contacting said gear or transmission with a lubricant composition wherein said lubricant composition has an ISOT score of about 3.0 or lower for varnish on the glass beaker or glass rod and a L-60-1 carbon/varnish (C/V) rating of at least about 7.5 and a L-60-1 sludge rating of at least about 9.4 and wherein said lubricant composition is substantially free of boron and has a total phosphorus content of less than about 500 ppm The present disclosure also provides a method for providing a boron-free lubricant composition capable of achieving a satisfying score on the ISOT test and the L-60-1 test comprising combining with a base oil, a lubricant additive package comprising a dispersant. and wherein the lubricant composition is substantially free of boron and has a total phosphorus content of less than about 500 ppm.

1 . A method for lubricating a gear or transmission comprising: 
 contacting said gear or transmission with a lubricant composition wherein said lubricant composition has an ISOT score of about 3.0 or lower for varnish on the glass beaker or glass rod and a L-60-1 carbon/varnish (C/V) rating of at least about 7.5 and a L-60-1 sludge rating of at least about 9.4 and wherein said lubricant composition is substantially free of boron and has a total phosphorus content of less than about 500 ppm.    
     
     
         2 . The method of  claim 1 , wherein the lubricant composition comprises a dispersant.  
     
     
         3 . The method of  claim 2 , wherein the dispersant is selected from the group consisting of: one or more of various types of ashless dispersants including succinimides, succinamides, succinic esters, and succinic ester-amides.  
     
     
         4 . The method of  claim 1 , wherein the lubricant composition further comprises at least one member of the group consisting of a dispersant, an inhibitor, an antiwear agent, an antifoam agent, and an extreme pressure agent.  
     
     
         5 . A method for providing a boron-free lubricant composition capable of achieving a satisfying score on the ISOT test and the L-60-1 test comprising combining with a base oil, a lubricant additive package comprising a dispersant, and wherein the lubricant composition is substantially free of boron and has a total phosphorus content of less than about 500 ppm.  
     
     
         6 . The method of  claim 5 , wherein the dispersant is selected from the group consisting of: one or more of various types of ashless dispersants including succinimides, succinamides, succinic esters, and succinic ester-amides.  
     
     
         7 . The method of  claim 5 , wherein the lubricant additive package further comprises an antiwear agent.  
     
     
         8 . The method of  claim 7 , wherein the weight ratio of the dispersant to the antiwear agent is from about 10:1 to about 2:1.  
     
     
         9 . The method of  claim 7 , wherein the antiwear agent is selected from the group consisting of: dihydrocarbyl polysulphides; sulphurized olefins; sulphurized fatty acid esters of both natural and synthetic origins; trithiones; sulphurized thienyl derivatives; sulphurized terpenes; sulphurized oligomers of C2-C8 monoolefins, and sulphurized Dieis-Alder adducts.  
     
     
         10 . The method of  claim 5 , wherein the lubricant additive package further comprises an inhibitor.  
     
     
         11 . The method of  claim 10 , wherein the weight ratio of the dispersant to the inhibitor is from about 1:17 to about 4:5.  
     
     
         12 . The method of  claim 10 , wherein the inhibitor is selected from the group consisting of: corrosion inhibitors and oxidation inhibitors.  
     
     
         13 . The method of  claim 10 , wherein the inhibitor is selected from the group consisting of thiadiazoles and triazoles.  
     
     
         14 . The method of  claim 5 , wherein the lubricant additive package further comprises an extreme pressure agent.  
     
     
         15 . The method of  claim 14 , wherein the ratio of the dispersant to the extreme pressure agent is from about 1:7 to about 1:2.  
     
     
         16 . The method of  claim 14 , wherein the extreme pressure agent is selected from the group consisting of sulfurized olefins, sulfurized fatty acid esters, and alkyl polysulfides.  
     
     
         17 . The method of  claim 5 , wherein the lubricant additive package further comprises an antifoam agent.  
     
     
         18 . The method of  claim 17 , wherein the weight ratio of the dispersant to the antifoam agent is from about 30:1 to about 5:1.  
     
     
         19 . The method of  claim 17 , wherein the antifoam agent is selected from the group consisting of siloxane-containing polymers.  
     
     
         20 . The method of  claim 5 , wherein the lubricant additive package further comprises an antiwear agent and an extreme pressure agent, wherein the weight ratio of the dispersant to the antiwear agent is from about 10:1 to about 2:1 and wherein the weight ratio of the dispersant to the extreme pressure agent is from about 1:7 to about 1:2.  
     
     
         21 . The method of  claim 5 , wherein the lubricant additive package further comprises an inhibitor and an extreme pressure agent, wherein the weight ratio of the dispersant to the inhibitor is from about 1:17 to about 4:5 and wherein the weight ratio of the dispersant to the extreme pressure agent is from about 1:7 to about 1:2.  
     
     
         22 . The method of  claim 5 , wherein the base oil comprises a mineral oil, a synthetic oil, or a mixture thereof.  
     
     
         23 . The method of  claim 5 , wherein a satisfying score on the ISOT test comprises an ISOT score of about 3.0 or lower for varnish on the glass beaker or glass rod.  
     
     
         24 . The method of  claim 5 , wherein a satisfying score on the L-60-1 test comprises a L-60-1 carbon/varnish (C/V) rating of at least about 7.5 and a L-60-1 sludge rating of at least about 9.4.  
     
     
         25 . The method of  claim 5 , wherein the lubricant composition is a gear oil.  
     
     
         26 . The method of  claim 5 , wherein the lubricant composition is a transmission oil.