KR100664428B1 - Lubricant compositions for providing anti-shudder performance and elastomeric component compatibility - Google Patents

Abstract

The present application discloses a composition and method for providing anti-shake performance in a power transmission fluid through the incorporation of a non-dispersant viscosity index improver. In addition, the disclosed compositions achieve improved compatibility of the elastomer component with the lubricant through the incorporation of a non-dispersion viscosity index improver.

Non-dispersion Viscosity Index Improver, Anti Shake Performance, Elastomer Component

Description

Lubricant composition that provides anti-shake performance and compatibility with elastomer components {LUBRICANT COMPOSITIONS FOR PROVIDING ANTI-SHUDDER PERFORMANCE AND ELASTOMERIC COMPONENT COMPATIBILITY}

1 shows the torque performance of a fluid according to an embodiment, measured using a ZF GK test apparatus.

Figure 2 shows the torque performance of the comparative fluid measured using the ZF GK test apparatus.

The present invention relates to a lubricating oil composition and a method of using the same for providing and / or improving anti-shudder performance of automobile transmission fluids. The present invention also provides a lubricating oil composition that provides and / or improves compatibility with an elastomeric component.

New and improved transmission systems are being developed by the automotive industry. These new systems often involve high energy requirements. Therefore, friction materials technology must be developed to meet the increasing energy requirements of these improved fluid systems.

The high velocity that occurs during engagement and disengagement of some of the newer transmission systems means that the friction system must be able to maintain a relatively constant friction during engagement. In order to minimize the "shuddering" of the material while transmission power is transmitted from one gear to another, it is important that the frictional engagement be relatively constant over a wide range of speeds and temperatures.

In particular, new high energy type friction materials have been developed and used. The new high-energy friction material can withstand high speeds with internal transmission board speeds of up to about 65 m / sec. It is also important that the friction material be useful under limited lubrication conditions. One of the materials developed for the application of automatic transmission is a material containing carbon fiber.

Given the new materials and greater demand for transmissions, there is a need for automotive power transmission fluids that provide specific frictional properties under very demanding conditions of speed, temperature and pressure. Changes in the frictional characteristics of a fluid as a function of relative sliding speed, temperature, or pressure can cause performance degradation that a vehicle driver can immediately sense. Such effects may include unacceptably long or short gear shifts, vehicle tremors or vibrations, noise, and / or coarse shifts (“gear shift shocks”). Thus, there is a need for transmission fluids that exhibit improved characteristics such as shear stress and friction stability at high temperatures and pressures. Such fluids will reduce device and performance issues while improving the time interval of fluid exchange. The fluid enables smooth engagement of the torque converter and the conversion clutch, thereby reducing tremor, vibration and / or noise during longer fluid life, and in some cases improving fuel economy.

Friction modifiers are used in the transmission fluid to regulate friction between surfaces (eg, members of the torque converter clutch or the conversion clutch) at low sliding speeds. As a result, the curve of friction vs. speed (uv) has a positive slope, which in turn allows for a smooth clutch engagement and "stick-slip" behavior (e.g. shaking, noise and roughness) Minimize conversion. However, many conventional friction modifiers are thermally unstable. Due to the continued exposure to heat, these additives may decompose, losing the benefits they provide for clutch performance.

In addition, degradation of structural elastomeric components or components such as seals, belts, gaskets, bushings, filters and / or hoses in engines, transmissions, gears and / or axles can occur. Such degradation may be due to the interaction between the elastomeric material of the component and the reactive or inhibiting component of the lubricating composition or fluid. Furthermore, the lubricant should provide suitable swelling of seals, gaskets and the like. A further object of the compositions and methods of the present invention is to reduce the inhibition of the seals, hoses, and similar components and components, to improve their compatibility with them, and to enhance their proper swelling.

Summary of Embodiments

In an embodiment, the power transmitting fluid used in the power train may comprise a large amount of base oil and a small amount of additive composition. The additive composition may comprise one or more non-dispersant viscosity index improvers, wherein the power transmission fluid provides the power transmission device with anti-shake performance.

In another embodiment, the lubricating oil having compatibility with the elastomeric component may comprise a small amount of additive composition having a large amount of base oil and one or more non-dispersion viscosity index improvers.

In another embodiment, a method of improving the anti-shake capability of a power transmission fluid includes a power transmission fluid using a power transmission fluid comprising a small amount of an additive composition comprising a large amount of base oil and at least one non-dispersion viscosity index improver. Lubrication.

In another embodiment, a method of improving torque performance of a power transmission fluid includes lubricating a power transmission fluid using a power transmission fluid comprising a small amount of an additive composition comprising a large amount of base oil and at least one non-dispersion viscosity index improver. It may include making it do.

In another embodiment, a method of improving the compatibility of the lubricant with the elastomeric component is achieved by using the fluid comprising a small amount of an additive composition comprising a large amount of base oil and one or more non-dispersion viscosity index improvers. Lubrication.

In another embodiment, a method of enhancing the seal swell of an elastomeric seal comprises applying an elastomeric seal using a lubricant comprising a small amount of an additive composition comprising a large amount of base oil and at least one non-dispersion viscosity index improver. Lubrication.

In another embodiment, the method of producing a power transmission fluid having anti-shake power may include adding a small amount of an additive composition having a non-dispersion viscosity index improver to a large amount of base oil.

In another embodiment, a method of preparing a lubricating oil having improved compatibility with an elastomer component may include adding a small amount of an additive composition having a non-dispersion viscosity index improver to a large amount of base oil.

Detailed description of the embodiments

As the power transmission fluid operates under increasingly severe conditions, the oil used to lubricate the transmission must be formulated to withstand higher temperatures and pressures. In order to reduce equipment problems and increase the time interval of transmission oil change, the oil must be formulated so that important oil properties change as little as possible under these stresses. In particular, the shear stress stability characteristics of the oil, which are highly dependent on the additive package, must remain relatively constant over a wide range of temperatures and operating speeds. This ensures smooth engagement of the torque transducer and the conversion clutch, minimized tremor, vibration and noise, and improved fuel economy, as constant viscosity allows for desirable hydraulic adjustment.

The present invention provides for compatibility with elastomeric components (eg, seals, gaskets, belts and / or hoses) of lubricants, as well as compositions and methods for providing and / or enhancing anti-shake performance of power transmission fluids. Or to improve the method. Non-dispersion viscosity index improvers are known to improve the rheological properties of power transmission fluids and / or lubricants, such as the viscosity index. Thus, the compositions of the present invention present one solution to complex problems, thereby presenting inherent cost benefits.

In an embodiment, the power transmission fluid may comprise a base oil and an additive composition. The additive composition may comprise a non-dispersion viscosity index improver. Non-dispersion viscosity index improvers differ from dispersion viscosity index improvers in that there is no dispersant functional group. Non-dispersion viscosity index improvers suitable for use in one or more of these embodiments include polymethacrylates, olefin copolymers, polystyrenes, metallocene polymers, polymers of hydrogenated dienes and / or copolymers thereof with vinylamines, hydrogenation Homopolymers of conjugated dienes or copolymers thereof with vinyl aromatic hydrocarbons, and the like. The latter broad range of molecular weight polymers can be used as base polymers for non-dispersion viscosity index improvers, which can include linear, branched or star shaped structures.

The presence of a non-dispersion viscosity index improver in the compositions and methods of this embodiment obviates and / or reduces the need for conventional friction-modifying agents or other agents that provide anti-shake performance. Furthermore, the inclusion of the non-dispersion viscosity index improver can improve the anti-shake characteristics of the fluid with respect to the fluid containing the dispersion viscosity index improver. Embodiments may include a non-dispersion viscosity index improver in an amount sufficient to provide and / or enhance anti-shake characteristics of the power transmission fluid. For example, the additive composition may include from about 0.01% to about 50% by weight of non-dispersion viscosity index improver. As a further example, the additive composition may comprise from about 1.0 wt% to about 25 wt% non-dispersion viscosity index improver. As another further example, the additive composition may include from about 3% to about 15% by weight of non-dispersion viscosity index improver.

In addition, certain embodiments provide and / or improve the compatibility of the elastomer components found inside automotive transmissions, including automatic and manual transmissions, gear components and / or axle components. The elastomeric component may include a seal, a hose, a gasket, a belt, and the like. Furthermore, the component may consist of an elastomeric material such as nitrile rubber, polyacrylate, silicone, fluoroelastomer and / or chlorinated polyethylene. The elastomeric component may fail to shrink, shrink or swell properly due to contact with certain chemicals contained in the lubricant. Furthermore, some chemicals, such as seal swelling agents, can improve the durability of the seals and hoses for lubricants. Embodiments disclosed herein have been found to improve tensile strength and / or elongation due to positive interactions with seals and hoses. Both of these factors are indicative of adequate seal swelling and resistance to degradation or durability. The embodiment includes a lubricating oil comprising a non-dispersion viscosity index improver.

The presence of a non-dispersed viscosity index improver in the compositions and methods of this embodiment eliminates and / or reduces the need for seal swelling agents or other agents that have conventionally been used. For example, the inclusion of a non-dispersion viscosity index improver in lubricating oil can improve compatibility with the elastomeric component of the lubricating oil. In particular, the improvement can be compared to a fluid comprising a dispersion viscosity index improver and / or a fluid comprising a conventional seal swelling agent.

Embodiments may include an appropriate amount of non-dispersion viscosity index improver sufficient to provide the desired swelling and / or to provide or enhance compatibility between the lubricating oil and the elastomeric component. For example, the additive composition may comprise from about 0.01% to about 50% by weight of non-dispersion viscosity index improver. As a further example, the additive composition may comprise from about 1.0 wt% to about 25 wt% non-dispersion viscosity index improver. As another further example, the additive composition may include from about 3% to about 15% by weight of non-dispersion viscosity index improver.

Basal oil

Suitable base oils for use in forming the transmission fluid composition may be selected from any of synthetic or natural oils or mixtures thereof. Natural oils are solvent or acid treated with animal and vegetable oils (eg beaver oil, swine oil) as well as mineral lubricants such as liquid petroleum, paraffinic, naphthenic or paraffinic-naphthenic mixed types. Mineral lubricants. Oils derived from coal or shale are also suitable. Base oils typically have a viscosity of about 2 to about 15 cSt, alternatively about 2 to about 10 cSt, at 100 ° C. Furthermore, gas-to-liquid stocks are also suitable.

Synthetic base oils include poly-alpha-olefins including alkyl esters of dicarboxylic acids, polyglycols and alcohols, polybutenes, alkylbenzenes, organic esters of phosphoric acid and polysilicon oils. Synthetic oils include hydrocarbon oils such as polymerized and interpolymerized olefins (eg, polybutylene, polypropylene, propylene isobutylene copolymers, etc.); Poly (1-hexene), poly- (1-octene), poly (1-decene) and the like and mixtures thereof; Alkylbenzenes (eg, dodecylbenzene, tetradecylbenzene, dinonylbenzene, di- (2-ethylhexyl) benzene, etc.); Polyphenyls (eg, biphenyls, terphenyls, alkylated polyphenyls, etc.); Alkylated diphenyl ethers and alkylated diphenyl sulfides and derivatives, analogs and homologs thereof, and the like.

Alkylene oxide polymers and copolymers in which the terminal hydroxyl groups are modified by esterification, etherification and the like and derivatives thereof form another class of known synthetic oils that can be used. Examples of such oils include: oils prepared by the polymerization of ethylene oxide or propylene oxide, alkyl and allyl ethers of the polyoxyalkylene polymers (eg, methyl-polyiso having an average molecular weight of about 1000). Propylene glycol ether, diphenyl ether of polyethylene glycol having a molecular weight of about 500 to 1000, diethyl ether of polypropylene glycol having a molecular weight of about 1000 to 1500, or the like) or mono- and polycarboxyl esters thereof, such as acetic acid ester , Mixed C _3-8 fatty acid esters, or C ₁₃ oxoacid diesters of tetraethylene glycol.

Other types of synthetic oils that may be used include dicarboxylic acids (e.g., phthalic acid, succinic acid, alkylsuccinic acid, alkenylsuccinic acid, maleic acid, azelaic acid, suveric acid, sebacic acid, fumaric acid, adipic acid, Linoleic acid dimer, malonic acid, alkylmalonic acid, alkenylmalonic acid, etc. and various alcohols (e.g. butyl alcohol, hexyl alcohol, dodecyl alcohol, 2-ethylhexyl alcohol, ethylene glycol, diethylene glycol monoether, propylene Esters with glycols and the like). Specific examples of the ester include dibutyl adipate, di (2-ethylhexyl) sebacate, di-n-hexyl fumarate, dioctyl sebacate, diisooctyl azelate, diisodecyl azelate, dioctyl phthalate, Didecyl phthalate, diecosyl sebacate, 2-ethylhexyl diester of linoleic acid dimer, complex ester formed by reaction of 1 mole of sebacic acid with 2 moles of tetraethylene glycol and 2 moles of 2-ethylhexanoic acid, and the like do.

Useful esters as synthetic oils include esters made from monocarboxylic acids of C ₅ to C ₁₂ and polyols and polyol ethers such as neopentyl glycol, trimethylol propane, pentaerythritol, dipentaerythritol, tripentaerythritol and the like. Included.

Accordingly, the base oil that can be used to prepare the transmission fluid composition disclosed herein is any of the base oils of Groups I to IV specified in the American Petroleum Institute Base Oil Interchangeability Guidelines. Can be selected from.

Base oil group ¹ Sulfur (% by weight) Saturated Body (wt%) Viscosity index  Group I  > 0.03  And / or  <90  80 to 120  Group II  ≤0.03  And  ≥90  80 to 120  Group III  ≤0.03  And  ≥90  ≥120  Group IV  All Polyalphaolefins (PAO)  Group Ⅴ  All other base oils not included in Groups I to IV ¹ Groups I to III are mineral oil base stocks.

As discussed above, the base oil may be a poly-alpha-olefin. Typically, poly-alpha-olefins are derived from monomers having about 4 to about 30, or about 4 to about 20, or about 6 to about 16 carbon atoms. Examples of useful poly-alpha-olefins include those derived from octenes, decenes, mixtures thereof and the like. The poly-alpha-olefins may have a viscosity of about 2 to about 15 cSt, or about 3 to about 12 cSt, or about 4 to about 8 cSt at 100 ° C. Examples of poly-alpha-olefins include 4 cSt poly-alpha-olefins at 100 ° C., 6 cSt poly-alpha-olefins at 100 ° C., and mixtures thereof. Mixtures of the foregoing poly-alpha-olefins and mineral oils can be used.

The base oil may be an oil derived from a Fischer-Tropsch synthesized hydrocarbon. Fischer-Tropsch synthesized hydrocarbons are made from synthesis gas containing H ₂ and CO using a Fischer-Tropsch catalyst. Such hydrocarbons typically require additional processing to be useful as base oil. For example, the hydrocarbon can be hydroisomerized using the process disclosed in US Pat. No. 6,103,099 or 6,180,575; Hydrocrack or hydroisomerize using processes disclosed in US Pat. No. 4,943,672 or 6,096,940; Dewaxed using the process disclosed in US Pat. No. 5,882,505; Or US Pat. No. 6,013,171; Hydroisomerized and dewaxed using the process disclosed in 6,080,301 or 6,165,949.

The crude, refined and refined oils (and mixtures of any two or more thereof) of the natural or synthetic forms disclosed above may be used as base oils. Crude oil is obtained directly from natural or synthetic raw materials without further purification. For example, the shale oil obtained directly from the retorting operation, the petroleum obtained directly from the primary distillation, or the ester oil obtained directly from the esterification process and used without further treatment may be crude oil. Refined oils are similar to crude oils except that they have been treated in one or more purification steps to enhance one or more properties. Many such purification techniques are known to those skilled in the art, such as solvent extraction, secondary distillation, acid or base extraction, filtration, percolation, and the like. Refined oils are obtained by processes similar to those used to obtain refined oils applied to refined oils already in service. The rerefined oils, also known as reclaimed or reprocessed oils, are often further processed by techniques to remove used additives, contaminants and oil decay products.

The base oil may be combined with the additive composition described in the embodiments herein to provide a power transmission fluid. The base oil may be present in the power transmission fluid in an amount of about 50% to about 95% by weight.

Any other ingredients

The power transmission fluid may also include conventional types of additives used to form automatic transmission fluid in addition to the components described above. The additives include ashless dispersants, friction modifiers, antioxidants, extreme pressure additives, preservatives, antiwear additives, anticorrosive additives, metal deactivators, antifoams, pour point depressants, air entrainment additives, Metallic detergents and / or additional seal swelling agents.

The additives used to form the compositions described herein may be blended into the base oil individually or in various subcombinations. However, it is suitable to combine all the components simultaneously using additive concentrates (ie combinations of additives with diluents such as hydrocarbon solvents). The use of additive concentrates takes advantage of the intercompatibility provided by the combination of components when simulating the actual plant formulation conditions in the form of additive concentrates. In addition, the use of thickeners reduces the blending time and reduces the likelihood of blending errors.

The power transmission fluids disclosed herein may include fluids suitable for any power transmission application, such as a step automatic transmissoin or manual transmission having a speed of about 3 to about 7. Furthermore, the power transmission fluid of the present invention is suitable for use in transmissions having sliding torque converters, locking torque converters, starting clutches and / or one or more conversion clutches. The transmission includes a 3-, 4-, 5-, 6- and 7-speed transmission, and continuously variable transmission (chain, belt or disc type). They can also be used in manual transmissions including automated manual and dual-clutch transmissions.

Example

In the following examples, a fluid comprising the following components prepared in the proportions disclosed below was tested. Various components were examined according to the respective examples below. Unless otherwise specified, the test samples are identical except for changing the components.

 Ingredient type  Example 1 Ratio in Final Fluid, Weight%  Example 2 Ratio in Final Fluid, Weight%  Antioxidant  0.1-2.5  0.2-0.5  Corrosion inhibitor  0-0.2  0-0.06  Thiadiazole  0-2.0  0.01-0.6  Antifoam  0-1.5  0.05-0.20  Friction Compensator  0-5.0  0.005-0.25  Dispersant  0-10  1-5%  Seal swelling agent  0-20  0-10  Polymethacrylate Viscosity Index Enhancer  0.5-30  3-25  Basestock  60-90  60-90  Thinner oil  0-20  2-5

Example 1

Two transmission fluid formations were tested to evaluate the vibration reduction efficiency. Each fluid has the same concentration of supplemental additives and differs only in the type of viscosity index enhancer.

Polymethacrylate non-dispersion viscosity index improver was used in Formulation A at a concentration of 5.13 wt%, and a viscosity index improver with dispersing function was used in Formulation B at a concentration of 5.13 wt%.

As shown in Figs. 1 and 2, shaking experiments were conducted by evaluating the friction characteristics using a ZF GK device on two automatic transmission fluids. The experiment was developed by ZF to measure the opening and closing performance of a slip-adjusted clutch. Interchangeable intermediate axes allow the measurement of frictional vibrations, which are the basis of "green" evaluation or which are the first shaking characteristics of the experimental fluid. The green flicker portion of the "GVRK-Coursetest CFT23" consists of a torque-adjusted continuous slip module comprising three 20-minute sections. All sequences go through 60 minutes of experiment time. During each 20 minute portion, the force is proportional to the sliding speed and the output torque. The test result is a constant clutch speed of 0.345 m / s (50.0 rpm) for the force fluctuations that regulate the output torque of 100 Nm, which remains constant. Each 20 minute portion was analyzed for torque fluctuations. Vibration was indicated due to data acquisition at 1000 Hz rate. A one minute stabilization period occurred between each successive sliding portion. The experimental fluid temperature was adjusted to 120 ° C.

The measured values in FIGS. 1 and 2 are expressed as torque versus a function of time. The fluctuation of the torque measurement is an indicator of tremor. A non-shake fluid will display a constant torque over time. A shivering fluid will display a varying torque over time.

The shaking experiment was conducted with the polymethacrylate non-dispersion viscosity index improver (formulation A) of FIG. 1 and the dispersion viscosity index improver (formulation B) of FIG. 2. The green tremor feature of Formulation A in FIG. 1 shows a reduction in green tremor associated with incorporation of a non-dispersion viscosity index improver. Experimental results using Formulation A demonstrate the absence of green flicker, as evidenced by a constant torque over time. Experimental results using Formulation B demonstrate a varying torque over time which is indicative of green tremor.

Example 2

The incorporation of the non-dispersion viscosity index improver into the lubricating oil was tested for compatibility by representative elastomer components. The component tested was a hose made of chlorinated polyethylene. Table 1 describes the results of several power transmission fluids tested with chlorinated polyethylene hoses. The performance is determined by the tensile strength and elongation of the hose at the end of the experiment. The larger the number, the better the performance. Sample 1 does not contain any of the non-dispersion viscosity index improver, the dispersion viscosity index improver, or the seal swelling agent. Sample 2 contains an equal amount of non-dispersion viscosity index improver and a dispersion viscosity index improver. Sample 3 contained an equivalent amount of non-dispersion viscosity index improver, dispersion viscosity index improver, and additional seal swelling agent. Sample 4 contains a non-dispersion viscosity index improver and a seal swelling agent. All other components in the fluids tested were identical.

Sample 1 Sample 2 Sample 3 Sample 4  Non-dispersion Viscosity Index Enhancer, Weight%  0.00  5.80  5.80  10.80  Dispersion Viscosity Index Enhancer, Weight%  0.00  5.80  5.80  0.00  Seal swelling agent weight%  0.00  0.00  0.40  0.60  The tensile strength,%  -55.07  -52.22  -51.89  -41.89  Elongation,%  -74  -77.74  -73.19  -68.48

The results shown in Table 1 show that Sample 4 with non-dispersion viscosity index improver demonstrates superior tensile strength compared to samples with less or no non-dispersity viscosity index improver. Moreover, the incorporation of seal swelling agents in Samples 3 and 4 did not provide significant advantages. In particular, the gain obtained when using only a non-dispersion viscosity index improver significantly exceeds the gain obtained by a formulation mixed with or without a seal swelling agent.

In many parts of the specification, reference is made to a number of US patents. All such references are expressly incorporated herein in detail as if described in detail herein.

Other embodiments will be apparent to those of skill in the art upon consideration of the specification and practice of the inventions disclosed herein. As used throughout this specification and claims, “one” may mean one or more. Unless specifically indicated, all numbers expressing quantities of ingredients, physical properties such as molecular weight, percentages, ratios, reaction conditions, etc., as used in this specification and claims are to be understood as being modified in all instances by the term "about." . Thus, unless indicated to the contrary, the numerical parameters set forth herein and in the claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, at least each numerical parameter should be construed in light of the significant numbers reported and by applying ordinary rounding techniques. Notwithstanding that the numerical ranges and parameters setting forth the broad scope of the invention are approximations, the numerical values set forth in the specific examples are described as precisely as possible. However, some values internally include some unavoidable error due to the standard deviation found in each of the above experimental measurements. It is intended that the specification and examples be considered as exemplary only by the scope and spirit of the invention as indicated by the following claims.

The present invention provides for compatibility with elastomeric components (eg, seals, gaskets, belts and / or hoses) of lubricants, as well as compositions and methods for providing and / or enhancing anti-shake performance of power transmission fluids. Or how to improve. Non-dispersion viscosity index improvers are known to improve the rheological properties of power transmission fluids and / or lubricants, such as the viscosity index. Thus, the compositions of the present invention present one solution to complex problems, thereby presenting inherent cost benefits.

Claims (36)

A power transmission fluid for a power unit, comprising: an improved anti-vibration performance as compared to a power transmission fluid in which the power transmitting fluid does not contain one or more non-dispersed viscosity index improvers and contains a dispersed viscosity index improver. fluids that provide power transmission to the power train: (a) a large amount of base oil; And (b) a small amount of additive composition comprising at least one non-dispersant viscosity index improver. The fluid of claim 1 wherein the non-dispersion viscosity index improver comprises a polymethacrylate viscosity index improver. The fluid of claim 1 wherein the non-dispersion viscosity index improver is present in the additive composition in an amount of 0.01% to 50% by weight. 4. The fluid of claim 3 wherein the non-dispersion viscosity index improver is present in the additive composition in an amount of 1% to 25% by weight. The fluid of claim 4 wherein the non-dispersion viscosity index improver is present in the additive composition in an amount of 3% to 15% by weight. The fluid of claim 1 wherein the base oil comprises one or more of natural lubricants, synthetic lubricants and mixtures of the foregoing. The fluid of claim 1 wherein the fluid does not contain a dispersant viscosity index improver. The fluid of claim 1 wherein the fluid is an automatic transmission, a continuously variable transmission, a sliding torque converter, a step automatic transmission, a clutch-to-clutch transmission. And a fluid suitable for use with a transmission with a wet starting clutch. delete An automatic transmission lubricated by the fluid of claim 1. The automatic transmission according to claim 10, wherein the transmission is a continuously variable transmission. Lubricating oils compatible with the elastomer component include fluids: (a) a large amount of base oil; And (b) Small amounts of additive composition having at least one non-dispersion viscosity index improver. 13. The fluid of claim 12, wherein the lubricating oil further promotes swelling of the elastomeric component. 13. The fluid of claim 12 wherein the non-dispersion viscosity index improver comprises a polymethacrylate viscosity index improver. 13. The fluid of claim 12 wherein the non-dispersion viscosity index improver is present in the additive composition in an amount of 0.01% to 50% by weight. 16. The fluid of claim 15, wherein said non-dispersion viscosity index improver is present in an additive composition in an amount of 1% to 25% by weight. 17. The fluid of claim 16 wherein the non-dispersion viscosity index improver is present in the additive composition in an amount of 3% to 15% by weight. 13. The fluid of claim 12, wherein the base oil comprises one or more of natural lubricants, synthetic lubricants and mixtures of the foregoing. 13. The seal, hose, or seal and hose of claim 12 wherein the elastomeric component comprises at least one of a seal, hose, gasket and belt. 13. The seal, hose, or seal and hose of claim 12 wherein the elastomer component consists of any one of chlorinated polyethylene, nitrile rubber, polyacrylate, fluoroelastomer and silicone. 13. The fluid of claim 12, wherein the lubricant is suitable for use in automatic transmissions, CVTs, sliding torque converters, step automatic transmissions, clutch-to-clutch transmissions and transmissions with wet start clutches. 13. The fluid of claim 12 wherein the compatibility is improved over a fluid that does not contain a non-dispersion viscosity index improver. 13. The fluid of claim 12 wherein the compatibility is improved relative to a fluid that does not contain a non-dispersion viscosity index improver and that contains a dispersed viscosity index improver. 13. The fluid of claim 12, wherein the fluid does not contain a dispersion viscosity index improver. 13. The fluid of claim 12, wherein the fluid further contains a seal swelling agent. 13. A method of lubricating a power transmission comprising adding the fluid of claim 12 to a power transmission having an elastomer component and operating therein. An automatic transmission lubricated with the lubricating oil of claim 12. 28. The automatic transmission of claim 27 wherein the transmission is a continuously variable transmission. A method of improving the vibration suppression force of a power transmission fluid, the method comprising: lubricating a power transmission with a power transmission fluid including: How to provide improved vibration suppression compared to transmission fluid: (a) a large amount of base oil; And (b) A small amount of an additive composition comprising at least one non-dispersion viscosity index improver. A method of improving torque performance of a power transmission fluid, the method comprising lubricating the power transmission fluid with a power transmission fluid comprising: (a) a large amount of base oil; And (b) A small amount of an additive composition comprising at least one non-dispersion viscosity index improver. A method of improving the compatibility of a lubricant with an elastomer component, the method comprising lubricating the elastomer component with a fluid comprising: (a) a large amount of base oil; And (b) A small amount of an additive composition comprising at least one non-dispersion viscosity index improver. 32. The method of claim 31 wherein the elastomeric component comprises one or more of a seal, a hose, a gasket and a belt. 32. The method of claim 31, wherein the elastomeric material consists of one of chlorinated polyethylene, nitrile rubber, polyacrylate, silicone, and fluoroelastomer. A method of promoting seal swelling of an elastomeric seal, the method comprising lubricating the elastomeric seal with a lubricating oil comprising: (a) a large amount of base oil; And (b) A small amount of an additive composition comprising at least one non-dispersion viscosity index improver. A method of producing a power transmission fluid having anti-shake performance, comprising: adding a small amount of an additive composition having a non-dispersion viscosity index improver to a large amount of base oil, wherein the power transmission fluid does not contain at least one non-dispersion viscosity index improver. And provide improved anti-shake performance as compared to power transmission fluids containing a dispersion viscosity index improver. A process for preparing a lubricating oil having improved compatibility with an elastomer component, comprising adding a small amount of an additive composition having a non-dispersion viscosity index improver to a large amount of base oil.

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