Power transmission fluids with enhanced extreme pressure and antiwear characteristics

Abstract

A fluid composition is described for extreme pressure applications. The fluid composition includes a base oil, and an additive composition comprising sulfurized fatty oil in an amount sufficient to provide at least about 1,000 ppm sulfur to the fluid composition, and dialkyl thiadiazole in an amount sufficient to provide at least about 500 ppm sulfur to the fluid composition. Fluids containing these respective amounts of sulfurized fatty oil and dialkyl thiadiazole exhibit failure loads which equal or exceed about 1750 pounds at 100° C. and 150° C., respectively, as measured according to a Falex EP test of ASTM D-3233.

1 . A fluid composition, comprising: 
 (1) a major amount of a base oil, and    (2) a minor amount of an additive comprising: 
 (A) sulfurized fatty oil in an amount sufficient to provide at least about 1,000 ppm sulfur to the fluid composition, and  
 (B) dialkyl thiadiazole in an amount sufficient to provide at least about 500 ppm sulfur to the fluid composition.  
   
     
     
         2 . The fluid composition of  claim 1 , wherein component (A) is present in an amount sufficient to provide about 1,000 ppm to about 2,500 ppm sulfur to the fluid composition, and component (B) is present in an amount sufficient to provide about 500 ppm to about 1,800 ppm sulfur to the fluid composition.  
     
     
         3 . The fluid composition of  claim 1 , wherein component (A) is present in an amount sufficient to provide about 1,300 ppm to about 2,100 ppm sulfur to the fluid composition, and component (B) is present in an amount sufficient to provide about 550 ppm to about 1,500 ppm sulfur to the fluid composition.  
     
     
         4 . The fluid composition of  claim 1 , wherein combined sulfur added to the fluid composition by the sulfurized fatty oil and dialkyl thiadiazole is least about 1,500 ppm.  
     
     
         5 . The fluid composition of  claim 1 , wherein combined sulfur added to the fluid composition by the sulfurized fatty oil and dialkyl thiadiazole is least about 2,500 ppm.  
     
     
         6 . The fluid composition of  claim 1 , wherein combined sulfur added to the fluid composition by the sulfurized fatty oil and dialkyl thiadiazole is least about 3,000 ppm.  
     
     
         7 . The fluid composition of  claim 1 , wherein component (A) is present in an amount of at least about 0.5 wt. %, and component (B) is present in an amount of at least about 0.15 wt. %, based on the transmission fluid.  
     
     
         8 . The fluid composition of  claim 1 , wherein component (A) is present in an amount of about 0.5 wt. % to about 5.0 wt. %, and component (B) is present in an amount an amount of about 0.15 wt. % to about 3.0 wt. %, based on the transmission fluid.  
     
     
         9 . The fluid composition of  claim 1 , wherein component (A) is present in an amount of about 0.7 wt. % to about 3.0 wt. %, and component (B) is present in an amount an amount of about 0.15 wt. % to about 1.0 wt. %, based on the transmission fluid.  
     
     
         10 . The fluid composition of  claim 1 , wherein component (A) is present in an amount of about 0.73 wt. % to about 3.0 wt. %, and component (B) is present in an amount of about 0.3 wt. % to about 1.0 wt. %, based on the transmission fluid.  
     
     
         11 . The fluid composition of  claim 1 , wherein component (A) is present in an amount of about 0.75 wt. % to about 3.0 wt. %, and component (B) is present in an amount of about 0.35 wt. % to about 1.0 wt. %, based on the transmission fluid.  
     
     
         12 . The fluid composition of  claim 1 , wherein component (A) is sulfurized transesterified triglyceride.  
     
     
         13 . The fluid composition of  claim 1 , wherein component (A) is selected from the group consisting of a sulfurized fat, a sulfurized fatty acid, a sulfurized fatty acid ester, and a sulfurized fatty olefin.  
     
     
         14 . The fluid composition of  claim 1 , wherein component (B) is a compound of the formula:  
       
         
           
           
               
               
           
         
       
       wherein R 1  and R 2  may be the same or different hydrocarbyl groups, and x any y independently may be integers from 0 to 8, and the sum of x and y being at least 1.  
     
     
         15 . The fluid composition of  claim 14 , wherein R 1  and R 2  are the same or different hydrocarbyl group having from about 6 to about 18 carbon atoms.  
     
     
         16 . The fluid composition of  claim 14 , wherein R 1  and R 2  may be the same or different hydrocarbyl group having about 8 to about 12 carbon atoms, and x and y each are 1.  
     
     
         17 . The fluid composition of  claim 1 , wherein component (A) is 2,5-bis(hydrocarbyldithio)-1,3,4-thiadiazole or a derivative thereof.  
     
     
         18 . The fluid composition of  claim 1 , wherein the base oil comprises one or more of a natural oil, a mixture of natural oils, a synthetic oil, a mixture of synthetic oils, a mixture of natural and synthetic oils, and a base oil derived from a Fischer-Tropsch or gas-to-liquid process.  
     
     
         19 . The fluid composition of  claim 1 , wherein the base oil has a kinematic viscosity of from about 2 centistokes to about 10 centistokes at 100° C.  
     
     
         20 . The fluid composition of  claim 1 , wherein the additive composition further comprises one or more of a detergent, a dispersant, a friction modifier, an antioxidant, an antiwear agent, an antifoam agent, a viscosity index improver, a copper corrosion inhibitor, an anti-rust additive, a seal swell agent, a metal deactivator, and an air expulsion additive.  
     
     
         21 . The fluid composition of  claim 1 , wherein the additive composition is present in an amount of about 10 wt. % to about 20 wt. %, based on the fluid composition.  
     
     
         22 . A transmission containing the fluid composition of  claim 1 .  
     
     
         23 . The transmission of  claim 22 , wherein the transmission comprises a continuously variable transmission.  
     
     
         24 . The transmission of  claim 22 , wherein the transmission comprises a dual clutch transmission.  
     
     
         25 . The transmission of  claim 22 , wherein the transmission comprises an automatic transmission.  
     
     
         26 . The transmission of  claim 22 , wherein the transmission comprises a manual transmission.  
     
     
         27 . The fluid composition of  claim 1 , wherein the fluid is suitable for use in a transmission employing one or more of an electronically controlled converter clutch, a slipping torque converter, a lock-up torque converter, a starting clutch, and one or more shifting clutches.  
     
     
         28 . The fluid composition of  claim 1 , wherein the fluid is suitable for use in a belt, chain, or disk-type continuously variable transmission, a 4-, 5-, 6-, or 7-speed automatic transmission, a manual transmission, an automated manual transmission, or a dual clutch transmission.  
     
     
         29 . The fluid composition of  claim 1 , wherein the fluid is suitable for use in an industrial gear or an automotive gear.  
     
     
         30 . A vehicle comprising an engine and a transmission, the transmission including the fluid of  claim 22 .  
     
     
         31 . A vehicle comprising a differential, the differential including a lubricant containing the fluid composition of  claim 1 .  
     
     
         32 . A fluid comprising a major amount of base oil, and a minor amount of an additive composition containing respective amounts of (A) sulfurized fatty oil and (B) dialkyl thiadiazole which, in combination, are effective, to provide a transmission fluid exhibiting failure loads which equal or exceed about 1750 pounds at 100° C. and 150° C., respectively, as measured according to a Falex EP test of ASTM D-3233.  
     
     
         33 . The fluid composition of  claim 32 , wherein component (A) is present in an amount sufficient to provide at least about 1,000 ppm sulfur to the fluid composition, and component (B) is present in an amount sufficient to provide at least about 500 ppm sulfur to the fluid composition.  
     
     
         34 . The fluid composition of  claim 32 , wherein component (A) is present in an amount sufficient to provide about 1,000 ppm to about 2,500 ppm sulfur to the fluid composition, and component (B) is present in an amount sufficient to provide about 500 ppm to about 1,800 ppm sulfur to the fluid composition.  
     
     
         35 . The fluid composition of  claim 32 , wherein component (A) is present in an amount sufficient to provide about 1,300 ppm to about 2,100 ppm sulfur to the fluid composition, and component (B) is present in an amount sufficient to provide about 550 ppm to about 1,500 ppm sulfur to the fluid composition.  
     
     
         36 . The fluid composition of  claim 32 , wherein the fluid is suitable for use in a transmission employing one or more of an electronically controlled converter clutch, a slipping torque converter, a lock-up torque converter, a starting clutch, and one or more shifting clutches.  
     
     
         37 . The fluid composition of  claim 32 , wherein the fluid is suitable for use in a belt, chain, or disk-type continuously variable transmission, a 4-, 5-, 6-, or 7-speed automatic transmission, a manual transmission, an automated manual transmission, or a dual clutch transmission.  
     
     
         38 . The fluid composition of  claim 32 , wherein the fluid is suitable for use in an industrial gear or an automotive gear.  
     
     
         39 . A transmission containing the fluid composition of  claim 32 .  
     
     
         40 . The transmission of  claim 39 , wherein the transmission comprises a continuously variable transmission.  
     
     
         41 . The transmission of  claim 39 , wherein the transmission comprises a dual clutch transmission.  
     
     
         42 . The transmission of  claim 39 , wherein the transmission comprises an automatic transmission.  
     
     
         43 . The transmission of  claim 39 , wherein the transmission comprises a manual transmission.  
     
     
         44 . A vehicle comprising an engine and a transmission, the transmission including the fluid of  claim 32 .  
     
     
         45 . A vehicle comprising a differential, the differential including a lubricant containing the fluid composition of  claim 32 .  
     
     
         46 . An additive composition comprising: 
 (A) sulfurized fatty oil in an amount sufficient to provide at least about 1,000 ppm sulfur to the fluid composition, and    (B) dialkyl thiadiazole in an amount sufficient to provide at least about 500 ppm sulfur to the fluid composition.    
     
     
         47 . An additive composition containing respective amounts of (A) sulfurized fatty oil and (B) dialkyl thiadiazole which, in combination, are effective, to provide a transmission fluid exhibiting failure loads which equal or exceed about 1750 pounds at 100° C. and 150° C., as measured according to a Falex EP test of ASTM D-3233.  
     
     
         48 . A method for improving extreme pressure and/or wear performance in power transmitting apparatus comprising: 
 1) adding a fluid to an power transmitting apparatus, said fluid comprising (a) a base oil, and (b) an additive package comprising sulfurized fatty oil in an amount sufficient to provide at least 1,000 ppm sulfur to the fluid, and dialkyl thiadiazole in an amount sufficient to provide at least 500 ppm sulfur to the fluid; and    2) operating the fluid in the power transmitting apparatus, wherein the extreme pressure and/or wear performance is improved relative to the extreme pressure and/or wear performance of a transmission without said fluid.    
     
     
         49 . The method of  claim 48 , wherein the base oil has a kinematic viscosity of from about 2 centistokes to about 10 centistokes at 100° C.  
     
     
         50 . The method of  claim 48 , wherein the additive composition further comprises one or more of a detergent, a dispersant, a friction modifier, an antioxidant, an antiwear agent, an antifoam agent, a viscosity index improver, a copper corrosion inhibitor, an antirust additive, a seal swell agent, a metal deactivator, and an air expulsion additive.  
     
     
         51 . The method of  claim 48 , wherein the power transmitting apparatus comprises a transmission.  
     
     
         52 . The method of  claim 48 , wherein the power transmitting apparatus comprises an industrial gear or an automotive gear.  
     
     
         53 . A method of increasing the service life of a transmission comprising operating in a transmission a fluid comprising: a) a base oil, and (b) an additive package comprising sulfurized fatty oil in an amount sufficient to provide at least 1,000 ppm sulfur to the fluid, and dialkyl thiadiazole in an amount sufficient to provide at least 500 ppm sulfur to the fluid, wherein the service life of the transmission is improved relative to the service life of a transmission without said fluid.