Anti-shudder additive composition and lubricating oil composition containing the same

Abstract

An anti-shudder additive composition comprising at least one neutral phosphite and at least one phosphorous-free hydrocarbyl substituted succinic dispersant selected from the group consisting of a hydrocarbyl bissuccinimide and a hydrocarbyl substituted succinic ester of a polyol and mixtures thereof, wherein the additive is used in transmission fluids to decrease shudder.

1 . An anti-shudder additive composition comprising: 
 (a) At least one neutral phosphite compound; and    (b) At least one hydrocarbyl substituted succinic dispersant selected from the group consisting of a hydrocarbyl bissuccinimide and a hydrocarbyl substituted succinic ester of a polyol and mixtures thereof, wherein the hydrocarbyl substituent has at least 50 carbon atoms,    wherein the additive composition does not comprise an ethoxylated amine, and wherein the additive composition does not comprise a primary amide of a long chain carboxylic acid, and provided that if the lubricating oil composition also contains a monosuccinimide, then the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 7:3.    
   
   
       2 . The anti-shudder additive composition according to  claim 1 , wherein the neutral phosphite compound is trihydrocarbyl phosphite.  
   
   
       3 . The anti-shudder additive composition according to 2, wherein the trihydrocarbyl phosphite is trialkyl phosphite.  
   
   
       4 . The anti-shudder additive composition according to  claim 3 , wherein the trialkyl phosphite is trilauryl phosphite.  
   
   
       5 . The anti-shudder additive composition according to  claim 1 , wherein the hydrocarbyl bissuccinimide is a borated hydrocarbyl bissuccinimide.  
   
   
       6 . The anti-shudder additive composition according to  claim 1 , wherein the hydrocarbyl substituted succinic ester of a polyol is an ester of pentaerythritol.  
   
   
       7 . The lubricating oil composition according to  claim 1 , wherein the lubricating oil composition also contains monosuccinimide and the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 7.5:2.5.  
   
   
       8 . The lubricating oil composition according to  claim 7 , wherein the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 8:2.  
   
   
       9 . The lubricating oil composition according to  claim 8 , wherein the ration of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 9:1.  
   
   
       10 . A lubricating oil composition comprising: 
 (a) a major amount of an oil of lubricating viscosity;    (b) an effective amount of an anti-shudder additive composition comprising: 
 (i) At least one neutral phosphite compound, and  
 (ii) At least one hydrocarbyl substituted succinic dispersant selected from the group consisting of a hydrocarbyl bissuccinimide and a hydrocarbyl substituted succinic ester of a polyol and mixtures thereof, wherein the hydrocarbyl substituent has at least 50 carbon atoms; and  
   wherein the additive composition does not comprise an ethoxylated amine, and wherein the additive composition does not comprise a primary amide of a long chain carboxylic acid, and provided that if the lubricating oil composition also contains a monosuccinimide, then the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 7:3.    
   
   
       11 . The lubricating oil composition according to  claim 10 , wherein the transmission fluid is an automatic transmission fluid.  
   
   
       12 . The lubricating oil composition according to  claim 10 , wherein the transmission fluid is a continuously variable transmission fluid.  
   
   
       13 . The lubricating oil composition according to  claim 10 , wherein the at least one neutral phosphite compound is a trihydrocarbyl phosphite.  
   
   
       14 . The lubricating oil composition according to  claim 13 , wherein the trihydrocarbyl phosphite is a trialkyl phosphite.  
   
   
       15 . The lubricating oil composition according to  claim 14 , wherein the trialkyl phosphite is trilauryl phosphite.  
   
   
       16 . The lubricating oil composition according to  claim 10 , wherein the hydrocarbyl bissuccinimide is a borated hydrocarbyl bissuccinimide.  
   
   
       17 . The lubricating oil composition according to  claim 10 , wherein the hydrocarbyl substituted succinic ester of a polyol is an ester of pentaerythritol.  
   
   
       18 . The lubricating oil composition according to  claim 10 , wherein the lubricating oil composition also contains monosuccinimide and the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 7.5:2.5.  
   
   
       19 . The lubricating oil composition according to  claim 18 , wherein the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 8:2.  
   
   
       20 . The lubricating oil composition according to  claim 19 , wherein the ration of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 9:1.  
   
   
       21 . A method of making an anti-shudder additive composition comprising: 
 mixing from about 0.1 wt % to about 90.9 wt % of at least one neutral phosphite compound with from about 9.1 wt % to about 99.9 wt % of at least one hydrocarbyl substituted succinic dispersant selected from the group consisting of a hydrocarbyl bissuccinimide and a hydrocarbyl substituted succinic ester of a polyol and mixtures thereof, in the absence of an ethoxylated amine and a primary amide of a long chain carboxylic acid, and provided that if the additive composition also contains a monosuccinimide, then the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 7:3.    
   
   
       22 . The method of making an anti-shudder additive composition according to  claim 21 , wherein the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimde is at least 7.5:2.5.  
   
   
       23 . The method of making an anti-shudder additive composition according to  claim 22 , wherein the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 8:2.  
   
   
       24 . The method of making an anti-shudder additive composition according to  claim 23 , wherein the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 9:1.  
   
   
       25 . A method of making a transmission fluid comprising: 
 mixing from about 0.11 wt % to about 11.0 wt % of the anti-shudder additive composition of  claim 2  with a major amount of an oil of lubricating viscosity.    
   
   
       26 . A method of reducing shudder in a transmission comprising: 
 (a) mixing an oil of lubricating viscosity with a shudder reducing effective amount of an anti-shudder additive composition comprising: 
 (i) at least one neutral phosphite compound;  
 (ii) at least one hydrocarbyl substituted succinic dispersant selected from the group consisting of a hydrocarbyl bissuccinimide and a hydrocarbyl substituted succinic ester of a polyol and mixtures thereof, wherein the hydrocarbyl substituent has at least 50 carbon atoms;  
 in the absence of an ethoxylated amine and a primary amide of a long chain carboxylic acid; and  
 provided that if the lubricating oil composition also contains monosuccinimide, then the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 7:3.  
   (b) adding the mixture of (a) to a transmission.    
   
   
       27 . The method of reducing shudder according to  claim 26 , wherein the lubricating oil composition also contains monosuccinimide and the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 7.5:2.5.  
   
   
       28 . The method of reducing shudder according to  claim 27 , wherein the lubricating oil composition also contains monosuccinimide and the ratio of the hydrocarbyl substituted succinic dispersant to monosuccinimide is at least 8:2.  
   
   
       29 . The method of reducing shudder according to  claim 28 , wherein the lubricating oil composition also contains monosuccinimide and the ration of the hydrocarbyl substituted succinic dispersant to monosuccimide is at least 9:1.  
   
   
       30 . The method of reducing shudder according to  claim 26 , wherein the transmission is an automatic transmission or a continuously variable transmission.