Hydrocarbon compositions to reduce scuffing and seizure of the metal on metal interface for continuously variable transmissions

Abstract

Hydrocarbon compositions such as PIB as partial base stock replacements in CVT fluids provide improved scuffing and seizure performance at metal on metal interfaces

1 . A method for lubricating a continuously variable transmission, comprising supplying thereto a lubricant comprising: 
 (a) an oil of lubricating viscosity;    (b) a isobutylene polymer present in an amount of at least 0.5 percent by weight; and    (c) an alkylated naphthalene or an alkylated benzene or combinations thereof present in an amount of at least 0.1 percent by weight.    
   
   
       2 . The method of  claim 2 , wherein said alkylated benzene is present in an amount of 0 to about 4 percent by weight.  
   
   
       3 . The method of  claim 2 , wherein said alkylated naphthalene is present in an amount of about 0.5 to about 4 percent by weight.  
   
   
       4 . The method of  claim 1 , wherein the lubricant further comprises an olefin copolymer other than the isobutylene copolymer of (b).  
   
   
       5 . The method of  claim 5 , wherein said olefin copolymer is an ethylene/propylene copolymer.  
   
   
       6 . The method of  claim 5 , wherein said olefin co-polymer is present in an amount of about 0.25 to about 2 percent by weight.  
   
   
       7 . The method of  claim 1 , wherein said isobutylene polymer is polyisobutylene, which is present in an amount of about 1 to about 10 percent by weight and comprises polyisobutylene of a number average molecular weight of about 500 to about 3000.  
   
   
       8 . The method of  claim 7 , wherein said isobutylene polymer comprises a mixture of polyisobutylene of: 
 about 1.0 to 6.0 percent by weight of polymer with a number average molecular weight of about 250 to about 1600 and    about 0.5 to 2.0 percent by weight of polymer with a number average molecular weight of about 1600 to about 3000.    
   
   
       9 . A composition suitable for lubricating a continuously variable transmission, comprising: 
 (a) an oil of lubricating viscosity;    (b) about 0.5 to about 4 percent by weight of an alkylated naphthalene    (c) 0 to about 4.0 percent by weight of alkyl benzene    (d) about 0.25 to about 2.0 percent by weight of an olefin copolymer    (e) about 1 to about 10 percent by weight of isobutylene polymer a number average molecular weight of about 500 to about 3000.