Lubricant Compositions

Abstract

The instant disclosure generally relates to lubricating compositions having an oil of lubricating viscosity, a mixture of dispersants including a high TBN dispersant having a number average molecular weight of 2000 or higher, a low TBN dispersant having a number average molecular weight of 2000 or higher, a magnesium detergent and a molybdenum compound. The lubricating compositions of the invention contain less than 120 ppm boron and are substantially free of low molecular weight dispersants.

Description

CROSS REFERENCE TO RELATED APPLICATION

[0001] This application claims the priority of U.S. Provisional Application No. 63 / 761,395 filed on Feb. 21, 2025.SUMMARY

[0002] The instant disclosure relates to a lubricating composition and methods of lubricating an engine with said lubricating composition. The lubricating composition comprises an oil of lubricating viscosity, a mixture of high molecular weight dispersants, a magnesium detergent, a molybdenum compound, wherein one of the dispersants is a boron containing dispersant and the lubricating composition contains less than 120 ppm boron. The mixture of dispersants includes a high TBN dispersant having a number average molecular weight of 2000 or higher and a low TBN dispersant having a number average molecular weight of 2000 or higher. The low TBN dispersant may also include a mixture of borated and non-borated dispersants.

[0003] The instant disclosure further relates to methods of lubricating an internal combustion engine by supplying to the engine the lubricating composition as described herein.DETAILED DESCRIPTION

[0004] The instant disclosure relates to lubricating compositions and methods of using the same.Oils of Lubricating Viscosity

[0005] One component of the disclosed compositions is an oil of lubricating viscosity. As used herein, an oil of lubricating viscosity may include natural and synthetic oils, oil derived from hydrocracking, hydrogenation, and hydrofinishing, unrefined, refined, re-refined oils or mixtures thereof. A more detailed description of unrefined, refined and re-refined oils is provided in International Publication WO2008 / 147704, paragraphs

[0054] to

[0056] (a similar disclosure is provided in US Patent Application 2010 / 197536, see

[0072] to

[0073] ). A more detailed description of natural and synthetic lubricating oils is described in paragraphs

[0058] to

[0059] respectively of WO2008 / 147704 (a similar disclosure is provided in US Patent Application 2010 / 197536, see

[0075] to

[0076] ). The cited portions of both references are incorporated herein. Synthetic oils may also be produced by Fischer-Tropsch reactions and typically may be hydroisomerised Fischer-Tropsch hydrocarbons or waxes. In one embodiment oils may be prepared by a Fischer-Tropsch gas-to-liquid synthetic procedure as well as other gas-to-liquid oils.

[0006] Suitable oils may be produced from biological, i.e. natural, sources or by bio-engineered processes. This includes both natural occurring oils, such as vegetable oils and triglyceride oils that may be further refined or purified by standard processes, and those oils that may be derived by biological conversion of a natural chemical into oil directly or by bio-formation of building block pre-cursor molecules capable of being further converted into oil by known processes.

[0007] Oils of lubricating viscosity may also be defined as specified in April 2008 version of “Appendix E-API Base Oil Interchangeability Guidelines for Passenger Car Motor Oils and Diesel Engine Oils”, section 1.3 Sub-heading 1.3. “Base Stock Categories”. The API Guidelines are also summarised in US Patent U.S. Pat. No. 7,285,516 (see column 11, line 64 to column 12, line 10), which are incorporated herein by reference.

[0008] In one embodiment the oil of lubricating viscosity may be an API Group I to IV mineral oil, an ester or a synthetic oil, or mixtures thereof. In one embodiment the oil of lubricating viscosity may be an API Group II, Group III, Group IV mineral oil, an ester or a synthetic oil, or mixtures thereof. In one embodiment, the oil of lubricating viscosity is an API Group III base oil.

[0009] The amount of the oil of lubricating viscosity present is typically the balance remaining after subtracting from 100 wt % the sum of the amount of the additive package according to the instant disclosure and additional, if any, additives. In some embodiments, the oil of lubricating viscosity may be from 80 to 95 wt % of the lubricating compositions. In other embodiments, the oil of lubricating viscosity may be from 80 to 90 wt % of the lubricating composition.

[0010] In the present disclosure, the oil of lubricating viscosity may have a kinematic viscosity measured at 100° C. of 2.4 m2 / s to 6.4 m2 / s. In some embodiments, the kinematic viscosity is from 4.0 m2 / s to 5.0 m2 / s or from 5.2 m2 / s to 5.8 m2 / s or from 6.0 m2 / s to 6.5 m2 / s. In other embodiments, the kinematic viscosity is 6.2 m2 / s or 5.6 m2 / s or 4.6 m2 / s.

[0011] The lubricating composition claimed herein may be in the form of a concentrate and / or a fully formulated lubricant. If the lubricating composition is in the form of a concentrate (which may be combined with additional oil to form, in whole or in part, a finished lubricant), the ratio of the components disclosed herein to the oil of lubricating viscosity and / or to diluent oil include the ranges of 1:99 to 99:1 by weight, or 80:20 to 10:90 by weight.Alkaline Earth Metal Detergent

[0012] The lubricating compositions disclosed herein further include an alkaline earth metal detergent. Suitable alkaline earth metal detergents include metal overbased detergents.

[0013] Metal overbased detergents, otherwise referred to as overbased detergents, metal-containing overbased detergents or superbased salts, are characterized by a metal content in excess of that which would be necessary for neutralization according to the stoichiometry of the metal and the particular acidic organic compound, i.e. the substrate, reacted with the metal. The overbased detergent may comprise one or more of non-sulfur containing phenates, sulfur containing phenates, sulfonates, salicylates, saligenins, salixarates, and mixtures thereof.

[0014] The amount of excess metal is commonly expressed in terms of substrate to metal ratio. The terminology “metal ratio” is used in the prior art and herein to define the ratio of the total chemical equivalents of the metal in the overbased salt to the chemical equivalents of the metal in the salt which would be expected to result from the reaction between the hydrocarbyl substituted organic acid; the hydrocarbyl-substituted phenol or mixtures thereof to be overbased, and the basic metal compound according to the known chemical reactivity and the stoichiometry of the two reactants. Thus, in a normal or neutral salt (i.e. soap) the metal ratio is one and, in an overbased salt, the metal ratio is greater than one, especially greater than 1.3. The overbased detergent of the invention may have a metal ratio of 5 to 30, or a metal ratio of 7 to 22, or a metal ratio of at least 11.

[0015] The metal-containing detergent may also include “hybrid” detergents formed with mixed surfactant systems including phenate and / or sulfonate components, e.g., phenate / salicylates, sulfonate / phenates, sulfonate / salicylates, sulfonates / phenates / salicylates, as described, for example, in U.S. Pat. Nos. 6,429,178; 6,429,179; 6,153,565; and 6,281,179. Where, for example, a hybrid sulfonate / phenate detergent is employed, the hybrid detergent would be considered equivalent to amounts of distinct phenate and sulfonate detergents introducing like amounts of phenate and sulfonate soaps, respectively. Overbased phenates and salicylates typically have a total base number of 180 to 450 TBN. Overbased sulfonates typically have a total base number of 250 to 600, or 300 to 500. Overbased detergents are known in the art.

[0016] Alkylphenols are often used as constituents in and / or building blocks for overbased detergents. Alkylphenols may be used to prepare phenate, salicylate, salixarate, or saligenin detergents or mixtures thereof. Suitable alkylphenols may include para-substitued hydrocarbyl phenols. The hydrocarbyl group may be linear or branched aliphatic groups of 1 to 60 carbon atoms, 8 to 40 carbon atoms, 10 to 24 carbon atoms, 12 to 20 carbon atoms, or 16 to 24 carbon atoms. In one embodiment, the alkylphenol overbased detergent is prepared from an alkylphenol or mixture thereof that is free of or substantially free of (i.e. contains less than 0.1 weight percent) p-dodecylphenol. In one embodiment, the lubricating composition of the invention contains less than 0.3 weight percent of alkylphenol, less than 0.1 weight percent of alkylphenol, or less than 0.05 weight percent of alkylphenol.

[0017] The overbased metal-containing detergent may be alkali metal or alkaline earth metal salts. In one embodiment, the overbased detergent may be sodium salts, calcium salts, magnesium salts, or mixtures thereof of the phenates, sulfur-containing phenates, sulfonates, salixarates and salicylates.

[0018] In one embodiment, the sulfonate detergent may be predominantly a linear alkylbenzene sulfonate detergent having a metal ratio of at least 8 as is described in paragraphs to of US Patent Publication 2005 / 065045 (and granted as U.S. Pat. No. 7,407,919). The linear alkylbenzene sulfonate detergent may be particularly useful for assisting in improving fuel economy. The linear alkyl group may be attached to the benzene ring anywhere along the linear chain of the alkyl group, but often in the 2, 3 or 4 position of the linear chain, and in some instances, predominantly in the 2 position, resulting in the linear alkylbenzene sulfonate detergent.

[0019] Salicylate detergents and overbased salicylate detergents may be prepared in at least two different manners. Carbonylation (also referred to as carboxylation) of a p-alkylphenol is described in many references including U.S. Pat. No. 8,399,388. Carbonylation may be followed by overbasing to form overbased salicylate detergent. Suitable p-alkylphenols include those with linear and / or branched hydrocarbyl groups of 1 to 60 carbon atoms. Salicylate detergents may also be prepared by alkylation of salicylic acid, followed by overbasing, as described in U.S. Pat. No. 7,009,072. Salicylate detergents prepared in this manner, may be prepared from linear and / or branched alkylating agents (usually 1-olefins) containing 6 to 50 carbon atoms, 10 to 30 carbon atoms, or 14 to 24 carbon atoms. In one embodiment, the overbased detergent of the invention is a salicylate detergent. In one embodiment, the salicylate detergent of the invention is free of unreacted p-alkylphenol (i.e., contains less than 0.1 weight percent). In one embodiment, the salicylate detergent of the invention is prepared by alkylation of salicylic acid.

[0020] In some embodiments, the metal of the alkaline earth metal detergent is selected from calcium, magnesium, or mixtures thereof. In one embodiment, the alkaline earth metal detergent is a calcium sulfonate detergent. In another embodiment, the alkaline earth metal detergent is a calcium salicylate detergent. In another embodiment, the alkaline earth metal detergent is a magnesium sulfonate detergent. In one embodiment, the alkaline earth metal detergent is a mixture of two or more alkaline earth metal detergents. In embodiments where the alkaline earth metal detergent is a mixture, the mixture may include a calcium sulfonate detergent, a calcium salicylate detergent, and a magnesium sulfonate detergent.

[0021] The alkaline earth metal detergent may be present in the lubricating composition in an amount sufficient to deliver at least 500 ppm, or at least 800 ppm, or even at least 1000 ppm alkaline earth metal to the lubricating composition. In another embodiment, where a mixture of detergents is used, calcium detergents may be present in an amount to deliver 400 ppm to 3000 ppm, or 600 ppm to 1500 ppm calcium, or even 700 ppm to 1200 ppm, or even 800 ppm to 1000 ppm calcium to the lubricating composition and a magnesium detergent may be present in an amount sufficient to deliver 100 ppm to 1000 ppm or even at least 200 ppm, or even 400 ppm to 800 ppm or 500 ppm to 800 ppm or 600 ppm to 700 ppm magnesium to the lubricating composition. In one embodiment, the magnesium detergent(s) and the calcium detergent(s) are present in an amount to deliver a magnesium to calcium ratio of from 0.5 to 0.8 or 0.65 to 0.75 or 0.6 to 0.7.Dispersants

[0022] The lubricating compositions of the present invention may also comprise an ashless polyolefin dispersant. The dispersant may be a succinimide dispersant, a polyolefin succinic acid ester, amide, or ester-amide, or mixtures thereof. In one embodiment, the dispersant may be borated. In one embodiment, the dispersant may be present as a single dispersant. In one embodiment, the dispersant may be present as a mixture of two or three different dispersants, wherein at least one may be a succinimide dispersant.

[0023] The succinimide dispersant may be a derivative of an aliphatic polyamine, or mixtures thereof. The aliphatic polyamine may be aliphatic polyamine such as an ethylenepolyamine, a propylenepolyamine, a butylenepolyamine, or mixtures thereof. In one embodiment, the aliphatic polyamine may be ethylenepolyamine. In one embodiment, the aliphatic polyamine may be selected from the group consisting of ethylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, polyamine still bottoms, and mixtures thereof.

[0024] The succinimide dispersant may be a derivative of an aromatic amine, an aromatic polyamine, or mixtures thereof. The aromatic amine may be 4-aminodiphenylamine (ADPA) (also known as N-phenylphenylenediamine), derivatives of ADPA (as described in United States Patent Publications 2011 / 0306528 and 2010 / 0298185), a nitroaniline, an aminocarbazole, an amino-indazolinone, an aminopyrimidine, 4-(4-nitrophenylazo) aniline, or combinations thereof. In one embodiment, the dispersant is derivative of an aromatic amine wherein the aromatic amine has at least three non-continuous aromatic rings.

[0025] The succinimide dispersant may be a derivative of a polyether amine or polyether polyamine. Typical polyether amine compounds contain at least one ether unit and will be chain terminated with at least one amine moiety. The polyether polyamines can be based on polymers derived from C2-C6 epoxides such as ethylene oxide, propylene oxide, and butylene oxide. Examples of polyether polyamines are sold under the Jeffamine® brand and are commercially available from Hunstman Corporation located in Houston, Texas.

[0026] The dispersant may be a N-substituted long chain alkenyl succinimide. Examples of N-substituted long chain alkenyl succinimide include polyisobutylene succinimide. Typically, the polyisobutylene from which polyisobutylene succinic anhydride is derived has a number average molecular weight of 350 to 5000, or 550 to 3000 or 750 to 2500. Succinimide dispersants and their preparation are disclosed, for instance in U.S. Pat. Nos. 3,172,892, 3,219,666, 3,316,177, 3,340,281, 3,351,552, 3,381,022, 3,433,744, 3,444,170, 3,467,668, 3,501,405, 3,542,680, 3,576,743, 3,632,511, 4,234,435, Re 26,433, and 6,165,235, 7,238,650 and EP Patent 0 355 895B1.

[0027] The dispersant may also be post-treated by conventional methods by a reaction with any of a variety of agents. Among these are boron compounds, urea, thiourea, dimercaptothiadiazoles, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydride, nitriles, epoxides, and phosphorus compounds.

[0028] The dispersant may be borated using one or more of a variety of agents selected from the group consisting of the various forms of boric acid (including metaboric acid, HBO2, orthoboric acid, H3BO3, and tetraboric acid, H2B407), boric oxide, boron trioxide, and alkyl borates. In one embodiment the borating agent is boric acid which may be used alone or in combination with other borating agents. Methods of preparing borated dispersants are known in the art. The borated dispersant may be prepared in such a way that they contain 0.1weight % to 3.5 weight % boron, or 1.0 weight % to 3.0 weight %, or 0.1 weight % to 2.5 weight % boron or 0.2 to 1.5 weight % boron or 0.3 to 1.0 weight % boron.

[0029] Suitable polyisobutylenes for use in the succinimide dispersant, may include those formed from polyisobutylene or highly reactive polyisobutylene having at least about 50 mol %, such as about 60 mol %, and particularly from about 70 mol % to about 90 mol % or greater than 90 mol %, terminal vinylidene content. Suitable polyisobutenes may include those prepared using BF3 catalysts. In one embodiment, the dispersant is prepared from a polyolefin having number average molecular weight (calculated based on total weight of polymer divided by the total number of molecules) of 350 to 3000 Daltons, or 500 to 1500 Daltons, or 800 to 1200 Daltons, and a vinylidene content of at least 50 mol %, or at least 70 mol %, or at least 90 mol %.

[0030] The dispersant may be prepared / obtained / obtainable from reaction of succinic anhydride by an “ene” or “thermal” reaction, by what is referred to as a “direct alkylation process.” The “ene” reaction mechanism and general reaction conditions are summarized in “Maleic Anhydride”, pages, 147-149, Edited by B. C. Trivedi and B. C. Culbertson and Published by Plenum Press in 1982. The dispersant prepared by a process that includes an “ene” reaction may be a polyisobutylene succinimide having a carbocyclic ring present on less than 50 mole %, or 0 to less than 30 mole %, or 0 to less than 20 mole %, or 0 mole % of the dispersant molecules. The “ene” reaction may have a reaction temperature of 180° C. to less than 300° C., or 200° C. to 250° C., or 200° C. to 220° C.

[0031] The dispersant may also be obtained / obtainable from a chlorine-assisted process, often involving Diels-Alder chemistry, leading to formation of carbocyclic linkages. The process is known to a person skilled in the art. The chlorine-assisted process may produce a dispersant that is a polyisobutylene succinimide having a carbocyclic ring present on 50 mole % or more, or 60 to 100 mole % of the dispersant molecules. Both the thermal and chlorine-assisted processes are described in greater detail in U.S. Pat. No. 7,615,521, columns 4-5 and preparative examples A and B.

[0032] The dispersant may be used alone or as part of a mixture of non-borated and borated dispersants. If a mixture of dispersants is used, there may be two to five, or two to three or two dispersants.

[0033] In one embodiment, the dispersants employed in the present invention are direct alkylation polyisobutylene succinimide dispersants having a number average molecular weight of 2000 or higher. In one embodiment, the lubricating composition of the invention includes a mixture of dispersants having high TBN and low TBN. As used herein, “high TBN” refers to dispersants that have a TBN measured on an oil free basis (ASTM D2986) of greater than 30 mg KOH / g, or even greater than 40 mg KOH / g, including 41, 42, 43, 44, 45, 46, 47, 48, 49 and 50 or 40 to 60. As used herein, “low TBN” refers to dispersants that have a TBN measured on an oil free (ASTM D2986) basis of 30 mg KOH / g or less, or even 25 mg KOH / g or less, or 18 to 29, including 19, 20, 21, 22, 23, 24, 25, 26, 27, 28 and 29.

[0034] In one embodiment, the lubricating composition contains up to contains up to 1 wt % or 0.5 wt % to 0.9 wt % or 0.6 wt % to 0.8 wt % of the high TBN dispersant. In an embodiment, the lubricating composition less than 2 wt % or 1.3 wt % to 1.8 wt % or 1.5 wt % to 1.7 wt % of the low TBN dispersant. In an embodiment of the invention, the weight ratio of the high TBN dispersant to the low TBN dispersant on an oil free basis is 0.3 to 0.6 or 0.4 to 0.5.

[0035] In some embodiments, the lubricating composition includes a mixture of low TBN dispersants, for example, a mixture of a first non-borated low TBN dispersant and a second low TBN borated dispersant. In an embodiment of the invention, the weight ratio of the first low TBN non-borated dispersant to the second low TBN non-borated dispersant is 0.1 to 0.6 or 0.2 to 0.6, or 0.2 to 0.5.

[0036] In one embodiment of the present invention, the lubricating composition is substantially free of or free of dispersants having a number average molecular weight of less than 2000 or even less than 1800. In an embodiment, the lubricating composition is free of polyisobutylene succinimide dispersants having a number average molecular weight of less than 2000 or even less than 1800. The lubricating composition of the present invention may contain the 2000 Mn or greater dispersants in amounts of at least 1 wt %, or at least 2 wt %, or up to 6 wt % or up to 7 wt % or up to 8 wt %, or 1 wt % to 5 wt %, or 2 wt % to 4 wt % of the lubricating composition.

[0037] In one embodiment, the low TBN borated dispersant used in the lubricating composition of the present invention is present in an amount to deliver 150 ppm or less, or even 120 ppm or less boron to the lubricating composition.Molybdenum Compound

[0038] In one embodiment, the invention provides a lubricating composition further comprising a molybdenum compound. The molybdenum compound may be selected from the group consisting of molybdenum dialkyldithiophosphates, molybdenum dithiocarbamates, amine salts of molybdenum compounds, and mixtures thereof. The molybdenum compound may provide the lubricating composition with 50 to 500 ppm, or 50 to 500 ppm, or 60 to 200 ppm, or 70 ppm to 150 ppm molybdenum.Other Additives

[0039] The lubricating compositions of the instant disclosure may optionally comprise one or more additional performance additives. These additional performance additives may include one or more anti-wear agents, antioxidants, metal deactivators, viscosity modifiers, friction modifiers, corrosion inhibitors, dispersant viscosity modifiers, extreme pressure agents, foam inhibitors, demulsifiers, pour point depressants, seal swelling agents, and any combination or mixture thereof. Typically, fully-formulated lubricating oil will contain one or more of these performance additives, and often a package of multiple performance additives.

[0040] In one embodiment, the lubricating composition includes one or more phosphorous containing anti-wear agents. In one embodiment, the antiwear agent may include an ashless antiwear agent. In one embodiment, the phosphorous containing may include zinc dialkyl dithiophosphate (“ZDDP”).

[0041] In one embodiment of the invention, ZDDP is present in an amount to deliver 300 ppm to 800 ppm or 400 ppm to 800 ppm or 400 ppm to 600 ppm zinc to the lubricating composition. In another embodiment of the present invention, ZDDP is present in an amount sufficient to deliver 300 ppm to 800 ppm, or 400 ppm to 700 ppm phosphorous to the lubricating composition.

[0042] In one embodiment, the lubricant composition of the present invention includes one or more antioxidants. For example, in one embodiment, the antioxidant may include an aryl amine antioxidant, such as arylamines, diarylamines, alkylated arylamines, or alkylated diaryl amines. In one embodiment of the present invention, the aryl amine antioxidant may comprise a hydrocarbyl substituted diphenylamine. In another embodiment, the lubricating composition of the present invention may contain a phenolic antioxidant. Exemplary phenolic antioxidants include hindered phenols, including hindered phenol esters, such as phenol alkyl esters, hindered phenol acetates, hindered phenol alkoxides, bis- and polyphenols, condensates of phenols with formic acid and mixtures thereof. Hindered phenol antioxidants often contain a secondary butyl and / or a tertiary butyl group as a sterically hindering group. The phenol group may be further substituted with a hydrocarbyl group (typically linear or branched alkyl) and / or a bridging group linking to a second aromatic group. In one embodiment, the lubricating composition may contain a sulfurized organic compound. The exemplary sulfurized organic compound helps to control wear in a lubricated device, such as an engine, particularly for extreme pressure conditions in automobile, truck and industrial engines. They can also have very good thermal oxidation stability and rust inhibition properties. The sulfurized organic compound may be selected from oligomeric polysulfides, alkyl polysulfides, sulfurized esters, sulfurized alpha olefins, sulfurized fats, and sulfurized soybean oil.

[0043] Sulfurized olefins can be prepared as described in U.S. Pat. No. 4,957,651. The method employs a cosulfurized mixture of two or more reactants selected from (1) at least one fatty acid ester of a polyhydric alcohol, (2) at least one fatty acid, (3) at least one olefin, and (4) at least one fatty acid ester of a monohydric alcohol. Reactant (3), the olefin component, includes at least one olefin. The olefin may be an aliphatic olefin, containing 4 to 40 carbon atoms, such as from 8 to 36 or 12 to 18 carbon atoms. Terminal olefins, or alpha-olefins, are particularly suitable, especially those having from 12 to 20 carbon atoms. A sulfurized organic compounds may be the reaction product of a sulfurizing agent and at least one Diels-Alder adduct, in a molar ratio of at least 0.75:1. The molar ratio of sulfur source to Diels-Alder adduct may be from 0.75:1 to 1:1.2. The Diels-Alder adducts can be prepared from dienophiles having at least one carboxylic ester group represented by —C(O)O—Ro, where Ro is the residue of a saturated aliphatic alcohol of up to 40 carbon atoms, the aliphatic alcohol from which —Ro is derived being a mono or polyhydric alcohol, which may be selected from alkylene glycols, alkanols, alkoxy-substituted alkanols, ethanol, ethoxyethanol, propanol, butanol, beta-diethylamino-ethanol, dodecyl alcohol, diethylene glycol, tripropylene glycol, tetrabutylene glycol, hexanol, octanol, isooctyl alcohol and mixtures thereof. Generally, not more than two —C(O)O—Ro groups will be present, and in one embodiment, only one —C(O)O—Ro group. Such materials can also be described as cyclohexene compounds bearing ester substituents. An example sulfurized organic compound of this type is sulfurized 4-carbobutoxy cyclohexene. This and other sulfurized organic compounds can be further treated with other materials such as an aryl phosphate, e.g., triphenyl phosphite.

[0044] The lubricating composition of the present invention may also contain an additional dispersant. Suitable dispersants may include carboxylic, amine, Mannich, post-treated, and polymeric dispersant. Dispersants are often known as ashless-type dispersants because, prior to mixing in a lubricating oil composition, they do not contain ash-forming metals and they do not normally contribute any ash forming metals when added to a lubricant and polymeric dispersants.

[0045] Another class of ashless dispersant is Mannich bases. Mannich dispersants are the reaction products of alkyl phenols with aldehydes (especially formaldehyde) and amines (especially polyalkylene polyamines). The alkyl group typically contains at least 30 carbon atoms.

[0046] Any of the described dispersants may also be post-treated by conventional methods by a reaction with any of a variety of agents. Among these are boron, urea, thiourea, dimercaptothiadiazoles, carbon disulfide, aldehydes, ketones, carboxylic acids, hydrocarbon-substituted succinic anhydrides, maleic anhydride, nitriles, epoxides, phosphorus compounds and / or metal compounds.

[0047] The optional dispersant can also be a polymeric dispersant. Polymeric dispersants are interpolymers of oilsolubilizing monomers such as decyl methacrylate, vinyl decyl ether and high molecular weight olefins with monomers containing polar substituents, e.g., aminoalkylacrylates or acrylamides and poly-(oxyethylene)-substituted acrylates.

[0048] In one embodiment, the dispersant may comprise an oxyalkylated hydrocarbyl phenol. For example, the oxyalkylated hydrocarbyl phenol may be represented by the structure:wherein each R2 is independently hydrogen or a hydrocarbyl group of 1 to 6 carbon atoms; R3 is hydrogen, a hydrocarbyl group of 1 to 24 carbon atoms, or an acyl group represented by —C(═O)R5, R5 is a hydrocarbyl group of 1 to 24 carbon atoms each R4 is independently a hydrocarbyl group of 1 to 220, or 20 to 220, wherein at least one R4 contains 25 to 200, or 35 to 180 or 40 to 180 to 60 to 180 or 40 to 96 carbon atoms; n=1 to 10; and m=1 to 3.In other embodiments, The R4 group of the formula above may be located in the para position relative to the oxyalkylated group, and the resultant formula is represented by the structure:wherein variables R2 to R5, and n, are defined previously.Dispersant viscosity modifiers include functionalized polyolefins, for example, ethylene-propylene copolymers that have been functionalized with an acylating agent such as maleic anhydride and an amine; polymethacrylates functionalized with an amine, or esterified styrene-maleic anhydride copolymers reacted with an amine. More detailed description of dispersant viscosity modifiers are disclosed in International Publication WO2006 / 015130 or U.S. Pat. Nos. 4,863,623; 6,107,257; 6,107,258; and 6,117,825. In one embodiment, the dispersant viscosity modifier may include those described in U.S. Pat. No. 4,863,623 (see column 2, line 15 to column 3, line 52) or in International Publication WO2006 / 015130 (see page 2, paragraph

[0008] and preparative examples are described at paragraphs

[0065] to

[0073] ).In one embodiment, the invention provides a lubricating composition further comprising a friction modifier. Examples of friction modifiers include long chain fatty acid derivatives of amines, fatty esters, or epoxides; fatty imidazolines such as condensation products of carboxylic acids and polyalkylene-polyamines; amine salts of alkylphosphoric acids; fatty alkyl tartrates; fatty alkyl tartrimides; or fatty alkyl tartramides. The term fatty, as used herein, can mean having a C8-22 linear alkyl group.

[0052] Friction modifiers may also encompass materials such as sulfurized fatty compounds and olefins, molybdenum dialkyldithiophosphates, molybdenum dithiocarbamates, sunflower oil or monoester of a polyol and an aliphatic carboxylic acid.

[0053] In one embodiment the friction modifier may be selected from the group consisting of long chain fatty acid derivatives of amines, long chain fatty esters, or long chain fatty epoxides; fatty imidazolines; amine salts of alkylphosphoric acids; fatty alkyl tartrates; fatty alkyl tartrimides; and fatty alkyl tartramides. The friction modifier may be present at 0 wt % to 6 wt %, or 0.05 wt % to 4 wt %, or 0.1 wt % to 2 wt % of the lubricating composition.

[0054] In one embodiment, the friction modifier may be a long chain fatty acid ester. In another embodiment the long chain fatty acid ester may be a mono-ester or a diester or a mixture thereof, and in another embodiment, the long chain fatty acid ester may be a triglyceride.

[0055] The lubricating composition may further include metal deactivators, including derivatives of benzotriazoles (typically tolyltriazole), dimercaptothiadiazole derivatives, 1,2,4-triazoles, 2-benzimidazoles, 2-alkyldithiobenzimidazoles, or alkyldithiobenzothiazoles; foam inhibitors, including copolymers of ethyl acrylate and 2-ethylhexylacrylate and copolymers of ethyl acrylate and 2-ethylhexylacrylate and vinyl acetate; demulsifiers including trialkyl phosphates, polyethylene glycols, polyethylene oxides, polypropylene oxides and (ethylene oxide-propylene oxide) polymers; and pour point depressants, including esters of maleic anhydride-styrene, polymethacrylates, polyacrylates or polyacrylamides.

[0056] Pour point depressants that may be useful in the compositions of the invention further include polyalphaolefins, esters of maleic anhydride-styrene, poly(meth)acrylates, polyacrylates or polyacrylamides.

[0057] The lubricant composition for an internal combustion engine may be suitable for any engine lubricant irrespective of the sulfur, phosphorus or sulfated ash (ASTM D-874) content. The sulfur content of the engine oil lubricant may be 1.1 wt % or less, or 0.9 wt % or less, or 0.5 wt % or less, or 0.3 wt % or less. In one embodiment, the sulfur content may be in the range of 0.001 wt % to 0.5 wt %, or 0.01 wt % to 0.3 wt % or 0.5 to 1.0 wt %. The phosphorus content may be 0.2 wt % or less, or 0.12 wt % or less, or 0.1 wt % or less, or 0.085 wt % or less, or 0.08 wt % or less, or even 0.06 wt % or less, 0.055 wt % or less, or 0.05 wt % or less. In one embodiment the phosphorus content may be 100 ppm to 1000 ppm, or 200 ppm to 900 ppm, or 300 to 875, or 400 to 700. The total sulfated ash content may be 2 wt % or less, or 1.5 wt % or less, or 1.1 wt % or less, or 1 wt % or less, or 0.8 wt % or less, or 0.75 wt % or less, or 0.7 wt % or less, 0.65 wt % or less. In one embodiment, the sulfated ash content may be 0.05 wt % to 0.9 wt %, or 0.1 wt % to 0.8 wt %.

[0058] In one embodiment, the lubricating composition may be an engine oil, wherein the lubricating composition may be characterized as having at least one of (i) a sulfur content of 0.5 wt % or less, (ii) a phosphorus content of 0.1 wt % or less, (iii) a sulfated ash content of 1.0 wt % or less, or combinations thereof.

[0059] Generally, the lubricant is added to the lubricating system of the internal combustion engine, which then delivers the lubricating composition to the critical parts of the engine, during its operation, that require lubrication. The engine components may have a surface of steel or aluminum (typically a surface of steel) and may also be coated, for example, with a diamondlike carbon (DLC) coating. Lubricant compositions of the present invention may improve the wear in the engine.

[0060] An aluminum surface may be comprised of an aluminum alloy that may be a eutectic or hyper-eutectic aluminum alloy (such as those derived from aluminum silicates, aluminum oxides, or other ceramic materials). The aluminum surface may be present on a cylinder bore, cylinder block, or piston ring having an aluminum alloy, or aluminum composite.

[0061] The internal combustion engine may be fitted with an emission control system or a turbocharger. Examples of the emission control system include diesel particulate filters (DPF), or systems employing selective catalytic reduction (SCR).

[0062] The instant lubricating compositions may also be used to reduce or eliminate Low Speed Preignition (“LSPI”) in an engine. In one embodiment, lubricating compositions disclosed herein may be used in a method of reducing LSPI in a direct injection engine by supplying the lubricating composition to said engine. LSPI events may be catastrophic in nature. Hence drastic reduction or even elimination of LSPI events during normal or sustained operation of a direct fuel injection engine is desirable.

[0063] When operating a direct injection engine at speeds less than or equal to 3,000 rpm and under a load with a break mean effective pressure (BMEP) of greater than or equal to 10 bars, an LSPI even may occur. A LSPI event may consist of one or more LSPI combustion cycles, and generally consists of multiple LSPI combustion cycles which occur in a consecutive fashion or alternating fashion with normal combustion cycles in between. Without being bound to a particular theory, LSPI may result from a combustion of oil droplet(s), or a droplet(s) of oil-fuel mixture, or combinations thereof, which may accumulate, for example, in the top land crevices volume of a piston, or the piston ring-land and ring-groove crevices. The lubricant oil may be transferred from below the oil control ring to the piston top land area due to unusual piston ring movements. At low speed, high load conditions, in-cylinder pressures dynamics (compression and firing pressures) may be considerably different from in-cylinder pressures at lower loads, particularly due to strongly retarded combustion phasing and high boost and peak compression pressures which can influence ring motion dynamics.

[0064] At the foregoing loads, LSPI, which may be accompanied by subsequent detonation and / or severe engine knock, can cause severe damage to the engine very quickly (often within 1 to 5 engine cycles). Engine knock may occur with LSPI given that, after the normal spark from the igniter is provided, multiple flames may be present. The present invention aims to provide a method for inhibiting or reducing LSPI events, the method involving supplying to the engine a lubricant composition as disclosed herein.

[0065] Generally, the lubricant is added to the lubricating system of the internal combustion engine, which then delivers the lubricating composition to the critical parts of the engine, during its operation, that require lubrication. The engine components may have a surface of steel or aluminum (typically a surface of steel) and may also be coated, for example, with a diamondlike carbon (DLC) coating.

[0066] An aluminum surface may be comprised of an aluminum alloy that may be a eutectic or hyper-eutectic aluminum alloy (such as those derived from aluminum silicates, aluminum oxides, or other ceramic materials). The aluminum surface may be present on a cylinder bore, cylinder block, or piston ring having an aluminum alloy, or aluminum composite.

[0067] The internal combustion engine may be fitted with an emission control system or a turbocharger. Examples of the emission control system include diesel particulate filters (DPF), or systems employing selective catalytic reduction (SCR).

[0068] The internal combustion engine of the present invention is distinct from a gas turbine. In an internal combustion engine, individual combustion events translate from a linear reciprocating force into a rotational torque through the rod and crankshaft. In contrast, in a gas turbine (which may also be referred to as a jet engine) a continuous combustion process generates a rotational torque continuously without translation and can also develop thrust at the exhaust outlet. These differences in operation conditions of a gas turbine and internal combustion engine result in different operating environments and stresses.

[0069] In one embodiment of the invention, the engine is operated at speeds between 500 rpm and 3000 rpm, or 800 rpm to 2800 rpm, or even 1000 rpm to 2600 rpm, or less than 3,000 rpm, or less than 2,500 rpm, or less than 2,000 rpm. Additionally, the engine may be operated with a break mean effective pressure of 10 bars to 15 bars, or 10 to 20 bars, or 10 to 30 bars or 12 bars to 24 bars.

[0070] In one embodiment, the instant disclosure relates to a lubricant composition disclosed herein wherein the lubricant composition is capable of reducing low speed pre-ignition events in a spark-ignited direct injection internal combustion engine operated under a load with a brake mean effective pressure (BMEP) of greater than or equal to 10 bars at speeds less than or equal to 3,000 rpm.

[0071] In another embodiment, the instant disclosure relates to a method for reducing low speed preignition by supplying to a spark-ignited direct injection internal combustion engine a lubricant composition as disclosed herein. The method further includes supplying to a spark-ignited direct injection internal combustion engine operated under a load with a break mean effective pressure (BMEP) of greater than or equal to 10 bars and at speeds less than or equal to 3,000 rpm, any one of the lubricant compositions as disclosed herein.

[0072] In some embodiments, the engine may be fueled with a liquid hydrocarbon fuel, a liquid nonhydrocarbon fuel, or mixtures thereof.

[0073] The instant disclosure further relates to use of any one of the lubricant compositions disclosed herein to reduce low speed preignition in a spark-ignited direct injection internal combustion engine.

[0074] The internal combustion engine of the present invention is distinct from a gas turbine. In an internal combustion engine, individual combustion events translate from a linear reciprocating force into a rotational torque through the rod and crankshaft. In contrast, in a gas turbine (which may also be referred to as a jet engine) a continuous combustion process generates a rotational torque continuously without translation and can also develop thrust at the exhaust outlet. These differences in operation conditions of a gas turbine and internal combustion engine result in different operating environments and stresses.

[0075] In some embodiments, the engine may be fueled with a liquid hydrocarbon fuel, a liquid nonhydrocarbon fuel, or mixtures thereof.

[0076] In one embodiment, the lubricating composition of the present invention has a Total Base Number (TBN) measured according to ASTM D2896-21 of less than 11, or less than 10, or less than 9, or less than 8, or at least 4, or at least 5, or at least 6.

[0077] In one embodiment the lubricating composition of the present invention has a viscosity grade according to SAE J300 of XW-YY, wherein X is 0, 5, 10 or 15, and YY is 8, 12, 16, 20, 30, or 40, for example, where X is 0 or 5 and YY is 20 or 30.

[0078] The present invention provides a method for reducing wear in an engine by supplying to the engine in an engine comprising supplying to the engine the lubricating composition described herein. The engine may be a heavy-duty diesel engine or a passenger car gasoline engine. The present invention also provides a method for reducing piston deposits comprising supplying to an engine the lubricating composition described herein. In addition, the present invention provides a method of reducing sulfated ash without lowering detergent ash. Further, the present invention provides for the use of the lubricating composition as described herein for improving oxidative stability of a lubricating composition or reducing piston deposits in an engine. Engines where the lubricating composition may be used include heavy duty diesel engines and gasoline powered passenger car engines.EXAMPLES

[0079] The disclosure will be further illustrated by the following examples, which set forth particularly advantageous embodiments. While the examples are provided to illustrate the invention, they are not intended to limit it.

[0080] A series of lubricating compositions were prepared as set forth in Table 1. Unless otherwise indicated all treat rates are oil free weight % of the total lubricating composition. As noted in Table 1, lubricating compositions were evaluated using the Sequence IIIH Engine Test (ASTM D8111) and the Sequence VIE Test (ASTM D8114).TABLE 1ComponentEx.1Ex.2Ex. 3Ex. 4Ex. 5Ex. 6Group III Base Oil85.1485.68587.18687.7Non dispersant Viscosity Modifier0.910.870.790.60.820.59Aminic Antioxidant0.90.981.181.170.980.98Magnesium Sulphonate Detergent0.430.40.480.430.40.4ZDDP0.690.50.770.70.480.74Sulphurised Olefin Antioxidant0.320.30.360.320.30.3Low TBN Direct Alkylation Polyisobutylene0.730.20.80.730.30.3Succinimide Dispersant(2000 Mn, TBN = 26)High TBN Direct Alkylation—0.75——0.750.75Polyisobutylene Succinimide Dispersant(2000 Mn, TBN = 41)Direct Alkylation Polyisobutylene1.351.341.61.651.341.34Succinimide Borated Dispersant (2000 Mn,TBN = 26)Molybdenum dithiocarbamate0.0680.070.080.070.0680.038Oleyl Amide Friction Modifier0.01—0.010.01——Glycerol monooleate friction modifier0.150.14————Calcium Sulfonate Detergent0.420.550.610.420.550.55Borate Ester0.092—0.10.09——Other Components18.88.368.226.718.066.36Sulfated Ash (ASTM D874 - calculated)0.760.770.930.770.770.8Boron (wt %)0.0130.0110.0160.0160.0120.011Calcium (wt %)0.0730.0940.0890.0730.0930.093Magnesium (wt %)0.0660.0620.0760.0710.0610.065Phosphorous (wt %)0.0610.0440.0710.0630.0440.068Sulfur (wt %)0.230.180.240.230.180.21Zinc (wt %)0.0670.0480.080.0690.0480.073Molybdenum (wt %)0.0140.0140.0150.0130.0130.007TBN (ASTM D2986)6.77.68.07.47.47.4Mg / Ca ratio0.90.70.910.70.7API Sequence IIIHWPD——3.73.94.64.6API Sequence VIEFEI Sum4.14.2————1Emulsifier, pour point depressant, diluent oil, diluent from additives.

[0081] It is known that some of the materials described above may interact in the final formulation, so that the components of the final formulation may be different from those that are initially added. The products formed thereby, including the products formed upon employing lubricant composition of the present invention in its intended use, may not be susceptible of easy description. Nevertheless, all such modifications and reaction products are included within the scope of the present invention; the present invention encompasses lubricant composition prepared by admixing the components described above.

[0082] Unless otherwise stated herein, reference to treat rates or amounts of components present in the lubricating compositions disclosed herein are quoted on an oil free basis, i.e., amount of active.

[0083] As used herein, the term “hydrocarbyl substituent” or “hydrocarbyl group” is used in its ordinary sense, which is well-known to those skilled in the art. Specifically, it refers to a group having a carbon atom directly attached to the remainder of the molecule and having predominantly hydrocarbon character including one or more double bonds. Examples of hydrocarbyl groups include: hydrocarbon substituents, that is, aliphatic (e.g., alkyl or alkenyl), alicyclic (e.g., cycloalkyl, cycloalkenyl) substituents, and aromatic-, aliphatic-, and alicyclic-substituted aromatic substituents, as well as cyclic substituents wherein the ring is completed through another portion of the molecule (e.g., two substituents together form a ring); substituted hydrocarbon substituents, that is, substituents containing non-hydrocarbon groups which, in the context of this invention, do not alter the predominantly hydrocarbon nature of the substituent (e.g., halo (especially chloro and fluoro), hydroxy, alkoxy, mercapto, alkylmercapto, nitro, nitroso, and sulfoxy); hetero substituents, that is, substituents which, while having a predominantly hydrocarbon character, in the context of this invention, contain other than carbon in a ring or chain otherwise composed of carbon atoms and encompass substituents as pyridyl, furyl, thienyl and imidazolyl. Heteroatoms include sulfur, oxygen, and nitrogen. In general, no more than two, or no more than one, non-hydrocarbon substituent will be present for every ten carbon atoms in the hydrocarbyl group; alternatively, there may be no non-hydrocarbon substituents in the hydrocarbyl group.

[0084] The present disclosure is not to be limited in terms of the particular embodiments described in this application, which are intended as illustrations of various aspects. Many modifications and variations can be made without departing from its spirit and scope, as will be apparent to those skilled in the art. Functionally equivalent methods and components within the scope of the disclosure, in addition to those enumerated herein, will be apparent to those skilled in the art from the foregoing descriptions. Such modifications and variations are intended to fall within the scope of the appended claims. The present disclosure is to be limited only by the terms of the appended claims, along with the full scope of equivalents to which such claims are entitled. It is to be understood that this disclosure is not limited to particular methods, reagents, compounds, or compositions, which can, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting.

[0085] As used in this document, the singular forms “a,”“an,” and “the” include plural references unless the context clearly dictates otherwise. Unless defined otherwise, all technical and scientific terms used herein have the same meanings as commonly understood by one of ordinary skill in the art. Nothing in this disclosure is to be construed as an admission that the embodiments described in this disclosure are not entitled to antedate such disclosure by virtue of prior invention. As used in this document, the term “comprising” means “including, but not limited to.”

[0086] While various compositions, methods, and devices are described in terms of “comprising” various components or steps (interpreted as meaning “including, but not limited to”), the compositions, methods, and devices can also “consist essentially of” or “consist of” the various components and steps, and such terminology should be interpreted as defining essentially closed-member groups.

[0087] With respect to the use of substantially any plural and / or singular terms herein, those having skill in the art can translate from the plural to the singular and / or from the singular to the plural as is appropriate to the context and / or application. The various singular / plural permutations may be expressly set forth herein for sake of clarity.

[0088] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation, no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particular claim containing such introduced claim recitation to embodiments containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and / or “an” should be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogous to “at least one of A, B, and C, etc.” is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general, such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and / or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and / or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B.”

[0089] In addition, where features or aspects of the disclosure may be described in terms of Markush groups, those skilled in the art will recognize that the disclosure is also thereby described in terms of any individual member or subgroup of members of the Markush group.

[0090] As used herein, “substantially free” means that the amount of the material in question is less than an amount that will affect the relevant performance of the fluid in a measurable way. “Substantially free” may also mean that the material in question is not intentionally added to the composition but does not exclude the presence of such material as contaminants. “Substantially free” may also mean that the material in question may be present in amounts lower than the detection limit of standard test methods now known to those skilled in the art or hereafter developed. In some embodiments, “substantially free” may mean less than 10 ppm by weight or even less than 5 ppm by weight.

[0091] As will be understood by one skilled in the art, for any and all purposes, such as in terms of providing a written description, all ranges disclosed herein also encompass any and all possible subranges and combinations of subranges thereof. Any listed range can be easily recognized as sufficiently describing and enabling the same range being broken down into at least equal halves, thirds, quarters, fifths, tenths, etc. As a non-limiting example, each range discussed herein can be readily broken down into a lower third, middle third and upper third, etc. As will also be understood by one skilled in the art all language such as “up to,”“at least,” and the like include the number recited and refer to ranges which can be subsequently broken down into subranges as discussed above. Finally, as will be understood by one skilled in the art, a range includes each individual member. Thus, for example, a group having 1-3 wt. % refers to groups having 1, 2, or 3 wt. %. Similarly, a group having 1-5 wt. % refers to groups having 1, 2, 3, 4, or 5 wt. %, and so forth, including all points therebetween.

[0092] Moreover, where a recited range for a treat rate is provided, it is contemplated that such range shall include treat rates for individual components and / or a mixture of components. Thus, for example, a range of 1 to 3 wt % contemplates that a given component may be present in a range of 1 to 3 wt % or that a mixture of similar components can be present in a range from 1 to 3 wt %.

[0093] As used herein, the term “about” means that a value of a given quantity is within ±20% of the stated value. In other embodiments, the value is within ±15% of the stated value. In other embodiments, the value is within ±10% of the stated value. In other embodiments, the value is within ±5% of the stated value. In other embodiments, the value is within ±2.5% of the stated value. In other embodiments, the value is within ±1% of the stated value.

[0094] Unless otherwise stated, “wt %” as used herein shall refer to the weight percent based on the total weight of the lubricating composition on an oil-free basis.

Claims

1. A lubricating composition comprising:a. an oil of lubricating viscosity;b. a high TBN dispersant having a number average molecular weight of 2000 or higher;c. a low TBN dispersant having a number average molecular weight of 2000 or higher;d. a magnesium detergent in an amount to deliver 400 ppm to 800 ppm or 500 ppm to 700 ppm or 600 ppm to 700 ppm magnesium to the lubricating composition;e. less than 120 ppm boron; andf. a molybdenum compound in an amount to provide 50 to 500 ppm, or 50 to 500 ppm, or 60 to 200 ppm, or 70 ppm to 150 ppm molybdenum to the lubricating composition.

2. The lubricating composition of claim 1, wherein the high TBN dispersant has an oil free TBN of greater than 30, or greater than 35, or greater than 40, or 40 to 45 as measured by ASTM D2896.

3. The lubricating composition of claim 1, wherein the low TBN dispersant has an oil free TBN of 30 or less, or 28 or less, or 18 to 28 as measured by ASTM D2896.

4. The lubricating composition of claim 1, wherein the lubricating composition contains up to 1 wt % or 0.5 wt % to 0.9 wt % or 0.6 wt % to 0.8 wt % of the high TBN dispersant.

5. The lubricating composition of claim 1, wherein the lubricating composition contains less than 2 wt % or 1.3 wt % to 1.8 wt % or 1.5 wt % to 1.7 wt % of the low TBN dispersant.

6. The lubricating composition of claim 1, wherein the low TBN dispersant comprises a first low TBN non-borated dispersant and a second low TBN borated dispersant.

7. The lubricating composition of claim 6, wherein a weight ratio of the first low TBN non-borated dispersant to the second low TBN borated dispersant is 0.1 to 0.6 or 0.2 to 0.6, or 0.2 to 0.5.

8. The lubricating composition of claim 7, wherein the boron in the lubricating composition is provided by the second low TBN borated dispersant.

9. The lubricating composition of claim 1, wherein the weight ratio of high TBN dispersant to low TBN dispersant is 0.3 to 0.6 or 0.4 to 0.5.

10. The lubricating composition of claim 1, wherein the high TBN dispersant is a polyisobutylene succinimide dispersant.

11. The lubricating composition of claim 1, wherein the low TBN dispersant is a polyisobutylene succinimide dispersant.

12. The lubricating composition of claim 1, wherein the lubricating composition is free of dispersants having a number average molecular weight of less than 2000 or less than 1800.

13. The lubricating composition of claim 1, further comprising a calcium detergent in an amount to deliver 600 ppm to 1500 ppm or 700 ppm to 1200 ppm or 800 ppm to 1000 ppm calcium to the lubricating composition.

14. The lubricating composition of claim 13, wherein a ratio of magnesium provided by the magnesium detergent to calcium provided by the calcium detergent is 0.5 to 0.8 or 0.65 to 0.75 or 0.6 to 0.7.

15. The lubricating composition of claim 1, further comprising a phosphorous containing antiwear agent in an amount to deliver 300 ppm to 800 ppm or 400 ppm to 700 ppm phosphorous to the lubricating composition.

16. The lubricating composition of claim 15, wherein the phosphorous containing antiwear agent comprises zinc dialkyldithiophosphate.

17. The lubricating composition of claim 16, wherein the zinc dialkyldithiophosphate is present in an amount to deliver 300 ppm to 800 ppm or 400 ppm to 800 ppm or 400 ppm to 600 ppm zinc to the lubricating composition.

18. The lubricating composition of claim 1, wherein the oil of lubricating viscosity comprises or consists of a Group III base oil.

19. The lubricating composition claim 1, wherein the lubricating composition has a viscosity grade according to SAE J300 of 0W-20 or 5W-30.

20. The lubricating composition of claim 1, wherein the lubricating composition has a TBN of 6 mg KOH / g to 9 mg KOH / g or 7 mg KOH / g to 8 mg KOH / g.

21. The lubricating composition of claim 1, wherein the lubricating composition further comprises an antioxidant selected from the group consisting of aminic antioxidants and sulfurized olefin antioxidants.

22. The lubricating composition of claim 1, wherein the molybdenum compound comprises molybdenum dithiocarbamate.

23. A method for lubricating an internal combustion engine comprising supplying to the internal combustion engine the lubricating composition of claim 1.

24. The method of claim 23, wherein the internal combustion engine is a spark-ignited direct injection internal combustion engine operated under a load with a break mean effective pressure (BMEP) of greater than or equal to 10 bars and at speeds less than or equal to 3000 rpm.

25. A method for improving fuel economy, comprising supplying to a spark-ignited direct injection internal combustion engine the lubricating composition of claim 1.

26. The method of claim 25, wherein the engine is operated under a load with a break mean effective pressure (BMEP) of greater than or equal to 10 bars and at speeds less than or equal to 3,000 rpm.

27. The method of claim 26, wherein the engine is fueled with a liquid hydrocarbon fuel, a liquid nonhydrocarbon fuel, or mixtures thereof.

28. A method for improving piston cleanliness, comprising supplying to a spark-ignited direct injection internal combustion engine the lubricating composition of claim 1.

29. The method of claim 28, wherein the engine is operated under a load with a break mean effective pressure (BMEP) of greater than or equal to 10 bars and at speeds less than or equal to 3,000 rpm.

30. The method of claim 29, wherein the engine is fueled with a liquid hydrocarbon fuel, a liquid nonhydrocarbon fuel, or mixtures thereof.

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