The invention is directed to a method for reducing low speed pre-ignition events in a spark-ignited direct injection internal combustion engine by supplying to the sump a lubricant composition which contains an oil of lubricating viscosity and an ashless dispersant. The ashless dispersant may be selected from succinimide compounds prepared from aliphatic or aromatic amines.

The present disclosure provides a lubricating oil composition which is excellent in metal fatigue life, wear resistance and electrical insulating properties, even when the composition has a reduced viscosity. The lubricating oil composition according to the present disclosure comprises: (A) a lubricating base oil; (B) from 0.6 to 4.0% by weight, based on the total weight of the lubricating oil composition, of a polydiene having a number average molecular weight of from 500 to 3,000 and containing a functional group on at least one end thereof; and (C) at least one selected from a phosphorus-based anti-wear agent and a phosphorus-based extreme pressure agent, the at least one agent being contained in such an amount that the content of phosphorus is from 50 to 500 ppm by weight based on the total weight of the lubricating oil composition.

The invention relates to the use of quaternized nitrogen compounds as a fuel and lubricant additive or kerosene additive, such as in particular as a detergent additive, for decreasing or preventing deposits in the injection systems of direct-injection diesel engines, in particular in common rail injection systems, for decreasing the fuel consumption of direct-injection diesel engines, in particular of diesel engines having common rail injection systems, and for minimizing the power loss in direct-injection diesel engines, in particular in diesel engines having common rail injection systems; the invention further relates to the use as an additive for petrol, in particular for operation of DISI engines.

A lubricant composition comprising an oil-soluble polyalkylene glycol; an ester compound selected from the group of natural esters and synthetic esters, and combinations thereof; and an additive mixture comprising an antioxidant and an anticorrosive, wherein the anticorrosive is selected from neutral alkali metal and alkaline earth metal salts of sulfonic acids, carboxylic acids, naphthoic acids, naphthenic acids, benzoic acids and phosphoric acids, and derivatives and combinations thereof.

A lubricant composition of an oil of lubricating viscosity and a phosphite ester reaction product of a monomeric phosphorous acid or an ester thereof with a first alkylene diol having two hydroxy groups in a 1,4 or 1,5 or 1,6 relationship and a second, alkyl-substituted, diol being a substituted 1,3-propylene diol, exhibits good wear and frictional performance.

An object of the present invention is to provide an ester-based lubricating base oil for a fluid bearing that has a high viscosity index and excellent evaporation resistance, hydrolytic stability, and low-temperature fluidity. The present invention relates to a lubricating base oil for a fluid bearing containing a compound represented by general formula (1):

##STR00001##

wherein R.sup.1 represents a linear C.sub.2-C.sub.16 alkyl group, m represents an integer of 2 to 10, and n represents an integer of 4 to 14.

A lubricating oil composition is provided which comprises (a) greater than 50 wt. % of a base oil of lubricating viscosity; and (b) 0.1 to 40 wt. % of an overbased alkaline earth metal alkyl-substituted hydroxyaromatic carboxylate, wherein the alkyl substituent is a residue derived from an isomerized alpha-olefin having from 12 to 40 carbon atoms, and having a TBN, on an actives basis, of less than 600 mg KOH/g, as determined by ASTM D 2896; wherein the lubricating oil composition is a monograde lubricating oil composition meeting specifications for SAE J300 revised January 2015 requirements for a SAE 20, 30, 40, 50, or 60 monograde engine oil, and has a TBN of 5 to 200 mg KOH/g, as determined by ASTM D2896.

A lubricant composition comprising an oil of lubricating viscosity and an N-hydrocarbyl-substituted γ-aminoester or γ-aminothioester, wherein the N-hydrocarbyl substituent comprises a hydrocarbyl group of at least 3 carbons atoms, with a branch at the 1 or 2 position of the hydrocarbyl chain, provides exhibits basicity and good seal performance.

The invention relates to a food-compatible high-temperature lubricant, more particularly a high-temperature oil and a high-temperature grease, comprising the following components: a) at least one oil selected from a trimellitic ester or a mixture of different trimellitic esters, alkylaromatics, preferably an aliphatically substituted naphthalene, or estolides; b) a hydrogenated or fully hydrogenated polyisobutylene or a mixture of hydrogenated or fully hydrogenated polyisobutylene; and c) additives individually or in combination.

In the case of the high-temperature grease, a thickener is added.

A lubricating composition for use in the crankcase of an engine comprising (i) a base oil; (ii) one or more organo-molybdenum compounds at a level sufficient to provide from 100 to 1000 ppmw of molybdenum; and (iii) from 0.2 wt % to 5.0 wt %, by weight of the lubricating composition, of one or more organic polymeric friction reducing additives, wherein the one or more organic polymeric friction reducing additives has a molecular weight ranging from 1000 to 30000 Daltons and is the reaction product of: a) a hydrophobic polymeric sub unit which comprises a hydrophobic polymer selected from polyolefins, polyacrylics and polystyrenyls; b) a hydrophilic polymeric sub unit which comprises a hydrophilic polymer selected from polyethers, polyesters, polyamides; c) optionally at least one backbone moiety capable of linking together polymeric sub units; and d) optionally a chain terminating group. The lubricating composition provides improvements in terms of reduced friction and wear, in addition to improved fuel economy performance.