Low viscosity transmission fluids with enhanced gear fatigue and frictional performance

• US 9,340,746 B1
• Filed: 04/13/2015
• Issued: 05/17/2016
• Est. Priority Date: 04/13/2015
• Status: Active Grant

• Current Assignee: Afton Chemical Corporation, Ford Motor Company
• Original Assignee: Afton Chemical Corporation, Ford Motor Company
• Inventors: Ved, Chintan N., Henly, Timothy J., Carroll, Joseph B., Cleveland, Christopher S., Strait, Kevin M.
• Primary Examiner(s): VASISTH, VISHAL V
• Application Number:
  US14/685,011
• Time in Patent Office: 400 Days
• Field of Search: 508/421
• US Class Current: 1/1
• CPC Class Codes: C10M 141/10 at least one of them being an organic phosphorus-containing compound
• CPC Class Codes: C10M 161/00 Lubricating compositions characterised by the additive being a mixture of a macromolecular compound and a non-macromolecular compound, each of these compounds being essential
• CPC Class Codes: C10M 2203/1006 used as base material
• CPC Class Codes: C10M 2203/1025 used as base material
• CPC Class Codes: C10M 2205/0285 used as base material
• CPC Class Codes: C10M 2215/28 Amides; Imides
• CPC Class Codes: C10M 2223/049 Phosphite
• CPC Class Codes: C10N 2020/02 Viscosity; Viscosity index
• CPC Class Codes: C10N 2030/06 Oiliness; Film-strength; Anti-wear; Resistance to extreme pressure
• CPC Class Codes: C10N 2030/42 Phosphor free or low phosphor content compositions
• CPC Class Codes: C10N 2030/76 Reduction of noise, shudder, or vibrations
• CPC Class Codes: C10N 2040/02 Bearings
• CPC Class Codes: C10N 2040/04 Oil-bath; Gear-boxes; Automatic transmissions; Traction drives
• CPC Class Codes: C10N 2040/042 for automatic transmissions
• CPC Class Codes: C10N 2040/044 for manual transmissions
• CPC Class Codes: C10N 2040/08 Hydraulic fluids, e.g. brake-fluids
• CPC Class Codes: C10N 2040/25 Internal-combustion engines
• CPC Class Codes: C10N 2040/30 Refrigerators lubricants or compressors lubricants
• CPC Class Codes: C10N 2060/12 by phosphorus or a compound containing phosphorus, e.g. PxSy

Abstract

A lubricant composition, a method for improving lubrication and a method for lubricating a machine. The lubricant composition includes a) a major amount of a base oil having a kinematic viscosity between 2 and 4 cSt at 100° C.; and b) dioctyl phosphite in an amount providing from about 100 to about 1000 ppm phosphorus to the lubricant composition. The lubricant composition has a phosphorus weight ratio of component (b) to total phosphorus in the lubricant composition of from 0.4:1 to less than about 0.8:1.

Claims

1. A lubricant composition comprising:

a) a major amount of a base oil having a kinematic viscosity between 2 and 4 cSt at 100°

C.;

b) dioctyl phosphite in an amount providing from about 150 to about 600 ppm phosphorus to the lubricant composition;

a phosphorylated dispersant comprising a phosphorylated polyisobutenyl bis-succinimide dispersant, wherein the dispersant provides from about 100 to about 300 ppm phosphorus to the lubricant composition; and

wherein the lubricant composition has a phosphorus weight ratio of component (b) to total phosphorus in the lubricant composition of from 0.4;

1 to less than about 0.8;

1.

2. The lubricant composition of claim 1, wherein component (b) provides from about 150 to about 550 ppm phosphorus to the lubricant composition.

3. The lubricant composition of claim 1, wherein the weight ratio of phosphorus provided by component (b) to the phosphorus provided by the phosphorylated dispersant ranges from about 0.4:

1 to about 6;

1.

4. The lubricant composition of claim 1, wherein component (a) has a kinematic viscosity between 3 and 4 cSt at 100°

C.

5. The lubricant composition of claim 1, further comprising one or more of the following:

an air expulsion additive, an antioxidant, a corrosion inhibitor, a foam inhibitor, a metallic detergent, an organic phosphorus compound, a seal-swell agent, and a viscosity index improver.

6. A method of lubricating a machine part comprising lubricating said machine part with the lubricant composition of claim 1.

7. The method of claim 6, wherein said machine part comprises a gear, an axle, a differential, an engine, a crankshaft, a pump, a hydraulic piston, a transmission, or a clutch.

8. The method of claim 7, wherein said transmission is selected from the group consisting of an automatic transmission, a manual transmission, an automated manual transmission, a semi-automatic transmission, a dual clutch transmission, a continuously variable transmission, and a toroidal transmission.

9. The method of claim 7, wherein said clutch comprises a continuously slipping torque converter clutch, a slipping torque converter clutch, a lock-up torque converter clutch, a starting clutch, one or more shifting clutches, or an electronically controlled converter clutch.

10. A method for improving the lubricating properties of a lubricating fluid while lubricating an automotive component requiring lubrication, comprising:

1) adding a lubricating fluid to an automotive component requiring lubrication, said fluid comprising (a) a major amount a base oil having a kinematic viscosity ranging from about 2 to about 4 cSt at 100°

C., and (b) dioctyl phosphite in an amount providing from about 150 to about 600 ppm phosphorus to the lubricant composition, a phosphorylated dispersant comprising a phosphorylated polyisobutenyl bis-succinimide dispersant, wherein the dispersant provides from about 100 to about 300 ppm phosphorus to the lubricant composition, and wherein the lubricant composition has a phosphorus weight ratio of component (b) to total phosphorus in the lubricant composition of from 0.4;

1 to less than about 0.8;

1,

2) operating the automotive component that contains the fluid,

wherein the fluid exhibits improved lubrication performance relative to the performance of a lubricating fluid free of the compound of

     1) (b).

11. The method of claim 10, wherein the weight ratio of phosphorus provided by component (b) to the phosphorus provided by the phosphorylated dispersant ranges from about 0.4:

1 to about 6;

1.

12. A lubricant composition having a kinematic viscosity of less than 5 cSt at 100°

C. comprising, (a) a major amount of base oil having a kinematic viscosity of from about 2 to less than about 4 cSt at 100°

C., and (b) dioctyl phosphite in an amount providing from about 150 to about 600 ppm phosphorus to the lubricant composition, a phosphorylated dispersant comprising a phosphorylated polyisobutenyl bis-succinimide dispersant, wherein the dispersant provides from about 100 to about 300 ppm phosphorus to the lubricant composition, and wherein the lubricant composition has a phosphorus weight ratio of component (b) to total phosphorus in the lubricant composition of from 0.4;

1 to less than about 0.8;

1, wherein the lubricant composition has a gear fatigue performance of greater than 40 hours.

13. The lubricant composition of claim 12, wherein the lubricant composition has a kinematic viscosity between 4.0 and 4.6 cSt at 100°

C.

14. The lubricant composition of claim 12, wherein the lubricant composition has a static breakaway coefficient of friction at 200 cycles in the Ford Clutch Friction Durability Test of from 0.109 to 0.119.

15. The lubricant composition of claim 12, wherein the lubricant composition has a midpoint dynamic coefficient of friction after 30,000 cycles in the Ford Clutch Friction Durability Test of from 0.14 to 0.16.

16. The lubricant composition of claim 12, wherein the lubricant composition has a stop time after 30,000 cycles in the Ford Clutch Friction Durability Test of less than 0.85 seconds.

17. A method of improving gear fatigue protection while maintaining friction control for an automatic transmission using low viscosity automatic transmission fluid by using an effective amount of a lubricating oil composition comprising or being made by admixing:

(1) a major amount of a base oil; and

(2) a gear fatigue improving effective amount of an additive combination comprising;

(a) dioctyl phosphite in an amount providing from about 150 to about 600 ppm phosphorus to the lubricant composition;

(b) a phosphorylated dispersant comprising a phosphorylated polyisobutenyl bis-succinimide dispersant, wherein the dispersant provides from about 100 to about 300 ppm phosphorus to the lubricant composition;

wherein the lubricant composition has a phosphorus weight ratio of dioctyl phosphite to total phosphorus in the lubricant composition of from 0.4;

1 to less than about 0.8;

1, and wherein the lubricating composition has a kinematic viscosity of between 2 and 5 cSt at 100°

C.

18. The method of claim 17 wherein the lubricating composition has a kinematic viscosity of between 2 and 4.6 cSt at 100°

C.

19. The method of claim 17 wherein the lubricating composition has a kinematic viscosity of between 4.0 and 4.6 cSt at 100°

C.