Automatic transmission fluid

Abstract

Provided are compositions for use in Automatic Transmission Fluids, and more specifically to Automatic Transmission Fluids made using Gas-to-Liquids lubricant base oils, formulated with minimal to no polymeric Viscosity Index improvers. The automatic transmission fluids disclosed herein contain a) a lubricant base oil having a Viscosity Index greater than a Viscosity Index Factor as calculated by the following equation: Viscosity Index Factor=28×ln(Kinematic Viscosity at 100° C.)+90; b) an automatic transmission fluid additive package; and c) less than 1.0 wt % Viscosity Index improver. The automatic transmission fluid has a kinematic viscosity at −7° C. of less than 300 mm 2 /s, and a kinematic viscosity at 100° C. between 5.0 and 6.0 mm 2 /s.

1 . An automatic transmission fluid comprising:
 a. a lubricant base oil having a Viscosity Index greater than a Viscosity Index Factor as calculated by the following equation:
   Viscosity Index Factor=28×ln(Kinematic Viscosity at 100° C.)+90; 
   b. an automatic transmission fluid additive package; and   c. less than 1.0 wt % Viscosity Index improver;   wherein the automatic transmission fluid has a kinematic viscosity at −7° C. of less than 300 mm 2 /s, and a kinematic viscosity at 100° C. between 5.0 and 6.0 mm 2 /s.   
     
     
         2 . The automatic transmission fluid of  claim 1 , comprising greater than 5 wt % automatic transmission fluid additive package. 
     
     
         3 . The automatic transmission fluid of  claim 1 , wherein the kinematic viscosity at −7° C. is less than 250 mm 2 /s. 
     
     
         4 . The automatic transmission fluid of  claim 1 , wherein the kinematic viscosity at −7° C. is less than 200 mm 2 /s. 
     
     
         5 . The automatic transmission fluid of  claim 1 , wherein the kinematic viscosity at −7° C. is less than 150 mm 2 /s. 
     
     
         6 . The automatic transmission fluid of  claim 1 , wherein the automatic transmission fluid has a Viscosity Index of greater than 150. 
     
     
         7 . The automatic transmission fluid of  claim 1 , wherein the automatic transmission fluid has a Viscosity Index of greater than 200. 
     
     
         8 . The automatic transmission fluid of  claim 1 , wherein the automatic transmission fluid has a Brookfield viscosity at −40° C. of less than 10,000 mPas. 
     
     
         9 . The automatic transmission fluid of  claim 1 , wherein the automatic transmission fluid has a Brookfield viscosity at −40° C. of less than 6,000 mPas. 
     
     
         10 . The automatic transmission fluid of  claim 1 , wherein the lubricant base oil is derived from a waxy feed. 
     
     
         11 . The automatic transmission fluid of  claim 1 , wherein the lubricant base oil is Fischer-Tropsch derived. 
     
     
         12 . The automatic transmission fluid of  claim 1 , comprising less than 0.5 wt % Viscosity Index improver. 
     
     
         13 . The automatic transmission fluid of  claim 1 , comprising approximately 0 wt % Viscosity Index improver. 
     
     
         14 . The automatic transmission fluid of  claim 1 , further comprising less than 0.5 wt % pour point depressant. 
     
     
         15 . The automatic transmission fluid of  claim 1 , wherein the lubricant base oil has a Viscosity Index greater than the Viscosity Index Factor plus 5. 
     
     
         16 . The automatic transmission fluid of  claim 1 , wherein the lubricant base oil has a Viscosity Index greater than the Viscosity Index Factor plus 15. 
     
     
         17 . An automatic transmission fluid comprising:
 a lubricant base oil having a Viscosity Index greater than a Viscosity Index Factor plus 15, wherein the Viscosity Index Factor is calculated by the following equation:
   Viscosity Index Factor=28×ln(Kinematic Viscosity at 100° C.)+90; 
   and wherein the automatic transmission fluid has a kinematic viscosity at −7° C. of less than 300 mm 2 /s and a kinematic viscosity at 100° C. between 5.0 and 7.0 mm 2 /s.   
     
     
         18 . The automatic transmission fluid of  claim 17 , wherein the lubricant base oil is derived from a waxy feed; 
     
     
         19 . The automatic transmission fluid of  claim 17 , wherein the kinematic viscosity at −7° C. is less than 250 mm 2 /s. 
     
     
         20 . A process for producing an automatic transmission fluid comprising:
 a. providing a lubricant base oil having a Viscosity Index greater than a Viscosity Index Factor as calculated by the following equation:
   Viscosity Index Factor=28×ln(Kinematic Viscosity at 100° C.)+90; 
   b. blending the lubricant base oil fraction with an automatic transmission fluid additive package; and   c. isolating an automatic transmission fluid comprising less than 1.0 wt %   Viscosity Index improver, wherein the automatic transmission fluid has a kinematic viscosity at −7° C. of less than 300 mm 2 /s, and a kinematic viscosity at 100° C. between 5.0 and 7.0 mm 2 /s.   
     
     
         21 . A process for producing an automatic transmission fluid comprising:
 a. performing a Fischer-Tropsch synthesis to provide a product stream;   b. isolating from the product stream a waxy feed;   c. hydroisomerizing the waxy feed using a shape selective intermediate pore size molecular sieve comprising a noble metal hydrogenation component under conditions of about 316° C. to about 399° C.;   d. isolating an isomerized oil;   e. hydrofinishing the isomerized oil to provide a Fischer-Tropsch derived lubricant base oil having a Viscosity Index greater than a Viscosity Index Factor as calculated by the following equation:
   Viscosity Index Factor=28×ln(Kinematic Viscosity at 100° C.)+90; 
   f. blending the Fischer-Tropsch derived lubricant base oil with an automatic transmission fluid additive package; and   
       g. isolating an automatic transmission fluid comprising less than 1.0 wt % Viscosity Index improver, wherein the automatic transmission fluid has a kinematic viscosity at −7° C. of less than 300 mm 2 /s, and a kinematic viscosity at 100° C. between 5.0 and 7.0 mm 2 /s. 
     
     
         22 . A process for producing an automatic transmission fluid comprising:
 a. performing a Fischer-Tropsch synthesis to provide a product stream;   b. isolating from the product stream a waxy feed;   c. hydroisomerizing the waxy feed using a shape selective intermediate pore size molecular sieve comprising a noble metal hydrogenation component under conditions of about 316° C. to about 399° C., wherein the intermediate pore size molecular sieve is selected from the group consisting of SAPO-11, SAPO-31, SAPO-41, SM-3, ZSM-22, ZSM-23, ZSM-35, ZSM-48, ZSM-57, SSZ-32, offretite, ferrierite, and combinations thereof and the noble metal hydrogenation component is selected from the group consisting of platinum, palladium, and combinations thereof;   d. isolating an isomerized oil;   e. vacuum distilling the isomerized oil to provide a lubricant base oil;   f. hydrofinishing the lubricant base oil to provide a Fischer-Tropsch derived lubricant base oil having a Viscosity Index greater than a Viscosity Index Factor as calculated by the following equation:
   Viscosity Index Factor=28×ln(Kinematic Viscosity at 100° C.)+90; 
   g. blending the Fischer-Tropsch derived lubricant base oil with an automatic transmission fluid additive package; and   h. isolating an automatic transmission fluid comprising less than 1.0 wt % Viscosity Index improver, wherein the automatic transmission fluid has a kinematic viscosity at −7° C. of less than 300 mm 2 /s, and a kinematic viscosity at 100° C. between 5.0 and 7.0 mm 2 /s.