Methods for improved power transmission performance and compositions therefor

Abstract

Advanced methods are provided for achieving improved power transmission performance, and unique fluid compositions useful for practicing such methods are also presented. In particular a method and related composition is provided for reducing NVH in a power transmission apparatus having a friction torque transfer apparatus, such as, e.g., a shifting clutch, comprising maintaining a negative ∂μ/∂T slope, and/or a negative ∂μ/∂P slope, during engagement of the friction torque transfer apparatus.

1 . A fluid composition, comprising: 
 (1) a major amount of a base oil, and    (2) a minor amount of an additive composition comprising alkoxylated amine, dihydrocarbyl phosphite, metallic detergent, and phosphorylated succinimide, in respective amounts effective for providing a negative ∂μ/∂T during engaging, slipping or modulating of a power transmission friction torque transfer apparatus lubricated therewith.    
     
     
         2 . The fluid composition of  claim 1 , comprising 0.002-0.5 wt % alkoxylated amine, 0.001-0.5 wt % dihydrocarbyl phosphite, 0.01-1.0 wt % metallic detergent, and 0.01-12 wt % phosphorylated succinimide.  
     
     
         3 . The fluid composition of  claim 1 , comprising 0.01-0.25 wt % alkoxylated amine, 0.01-0.2 wt % dihydrocarbyl phosphite, 0.01-0.7 wt % metallic detergent, and 0.01-10 wt % phosphorylated succinimide.  
     
     
         4 . The fluid composition of  claim 1 , wherein the additive composition is present in an amount of about 3 wt % to about 20 wt %, based on the fluid composition.  
     
     
         5 . The fluid composition of  claim 1 , wherein the additive composition is present in an amount of about 5 wt % to about 15 wt %, based on the fluid composition.  
     
     
         6 . The fluid composition of  claim 1 , wherein the fluid composition is formulated such that the fluid composition comprises a viscosity at 100° C. of <6 cSt, a viscosity at 40° C. of <30 cSt, and a Brookfield Viscosity at −40° C. of <10,000 cP, and wherein the ∂μ/∂T slope value is determined from coefficient of friction and temperature measurements taken on an SAE #2 Machine.  
     
     
         7 . 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.  
     
     
         8 . The fluid composition of  claim 1 , wherein the additive composition further comprises one or more of a additional friction modifier, an additional detergent, an additional dispersant, 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.  
     
     
         9 . An additive composition comprising alkoxylated amine, dihydrocarbyl phosphite, metallic detergent, and phosphorylated succinimide, in respective amounts effective for providing a negative ∂μ/∂T during engagement of a power transmission shifting clutch lubricated therewith.  
     
     
         10 . A method of reducing NVH in a power transmission apparatus having a friction torque transfer apparatus comprising lubricating the friction torque transfer apparatus with a fluid composition that provides a negative ∂μ/∂T during engaging, slipping or modulating the friction torque transfer apparatus, said fluid comprising alkoxylated amine, dihydrocarbyl phosphite, metallic detergent, and phosphorylated succinimide, in respective amounts effective therefor.  
     
     
         11 . A method for improving anti-NVH control performance in a power transmitting apparatus comprising: 
 A) adding a fluid to a power transmitting apparatus, said fluid comprising (i) a base oil, and (ii) an additive package comprising alkoxylated amine, dihydrocarbyl phosphite, metallic detergent, and phosphorylated succinimide; and    B) operating the fluid in the power transmitting apparatus, wherein the additive package being present in an amount effective for providing a negative ∂μ/∂T during engaging, slipping or modulating of a power transmission friction torque transfer apparatus lubricated therewith.    
     
     
         12 . The method of  claim 11 , wherein the friction torque transfer apparatus is selected from the group consisting of a shifting clutch, a starting clutch, a torque converter clutch, a band clutch, disk or plate clutch, and a limited slip differential clutch.  
     
     
         13 . The method of  claim 11 , wherein the friction torque transfer apparatus comprises a shifting clutch.  
     
     
         14 . The method of  claim 11 , wherein the fluid composition is formulated such that the fluid composition comprises a viscosity at 100° C. of <6 cSt, a viscosity at 40° C. of <30 cSt, and a Brookfield Viscosity at −40° C. of <10,000 cP, and wherein the ∂μ/∂T slope value is determined from coefficient of friction and temperature measurements taken on an SAE #2 Machine.  
     
     
         15 . A method of reducing NVH in a power transmission apparatus having a friction torque transfer apparatus comprising lubricating the friction torque transfer apparatus with a fluid composition that provides a negative ∂μ/∂P during engaging, slipping or modulating the friction torque transfer apparatus, said fluid comprising alkoxylated amine, dihydrocarbyl phosphite, metallic detergent, and phosphorylated succinimide, in respective amounts effective therefor.  
     
     
         16 . A transmission containing the fluid composition of  claim 1 .  
     
     
         17 . The transmission of  claim 16 , wherein the transmission comprises a continuously variable transmission.  
     
     
         18 . The transmission of  claim 16 , wherein the transmission comprises a dual clutch transmission.  
     
     
         19 . The transmission of  claim 16 , wherein the transmission comprises an automatic transmission.  
     
     
         20 . The transmission of  claim 16 , wherein the transmission comprises a manual transmission.  
     
     
         21 . The transmission of  claim 16 , wherein the transmission comprises 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.  
     
     
         22 . The transmission of  claim 16 , wherein the transmission comprises a belt, chain, or disk-type continuously variable transmission, a 4-speed or more automatic transmission, a manual transmission, an automated manual transmission, or a dual clutch transmission.  
     
     
         23 . A vehicle comprising an engine and a transmission, the transmission including the fluid composition of  claim 1.