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 overbased sodium detergent. The metal overbased detergent may be selected from sulfonate detergents, phenate detergents, and salicylate detergents, including sulfonate detergents with a metal ratio of at least 5.

A lubricating oil for hybrid engine includes a major amount of an oil of lubricating viscosity; a boron-containing compound in an amount to provide 50 to 300 ppm of boron to lubricating oil composition; an overbased calcium salicylate or a mixture of an overbased calcium sulfonate and overbased calcium salicylate individually having a total base number of greater than 150 mg KOH/g, measured by the method of ASTM D-2896, present in an amount that provides 800 ppm to 1800 ppm of calcium to the lubricating oil composition; zinc dithiophosphate (ZnDTP) in an amount to bring from 100 to 800 ppm of phosphorus to the lubricating oil composition; and a non-dispersant comb polymethacrylate (PMA) viscosity index improver (VII). The boron-containing compound includes a borated dispersant. The KV at 100 C. of the lubricating oil composition is from 6 cSt to 8.5 cSt, the KV at 40 C. of the lubricating oil composition is from 25 cSt to 35 cSt, and the VI of the lubricating oil composition is greater than 200.

A lubricating oil for hybrid engine includes a major amount of an oil of lubricating viscosity; a boron-containing compound in an amount to provide 50 to 300 ppm of boron to lubricating oil composition; an overbased calcium salicylate or a mixture of an overbased calcium sulfonate and overbased calcium salicylate individually having a total base number of greater than 150 mg KOH/g, measured by the method of ASTM D-2896, present in an amount that provides 800 ppm to 1800 ppm of calcium to the lubricating oil composition; zinc dithiophosphate (ZnDTP) in an amount to bring from 100 to 800 ppm of phosphorus to the lubricating oil composition; and a non-dispersant comb polymethacrylate (PMA) viscosity index improver (VII). The boron-containing compound includes a borated dispersant. The KV at 100 C. of the lubricating oil composition is from 6 cSt to 8.5 cSt, the KV at 40 C. of the lubricating oil composition is from 25 cSt to 35 cSt, and the VI of the lubricating oil composition is greater than 200.

A method for improving wear protection, while maintaining or improving deposit control and cleanliness, in an engine or other mechanical component lubricated with a lubricating oil by using as the lubricating oil a formulated oil. The formulated oil has a composition including a lubricating oil base stock as a major component, and one or more lubricating oil additives including at least one borated detergent, as a minor component. The at least one borated detergent comprises a borated alkaline earth metal sulfonate. The borated alkaline earth metal sulfonate is present in an amount sufficient to provide a total boron concentration of about 300 parts per million or greater in the formulated oil. Wear protection is improved, and deposit control and cleanliness are maintained or improved, as compared to wear protection, deposit control and cleanliness achieved using a lubricating oil containing a borated additive other than the at least one borated alkaline earth metal sulfonate.

The disclosure relates to methods of operating transmissions and for providing bearing pitting protection and a passing static friction performance according to Caterpillar TO-4 SEQ 1221 in a transmission including lubricating the transmission with a transmission fluid composition comprising: greater than 50 wt. % of a base oil of lubricating viscosity; an amount of one or more overbased calcium sulfonate detergent(s) to provide from about 2000 ppm to about 5000 ppm of calcium; an amount of one or more zinc dialkyl dithiophosphate compound(s) to provide from about 700 ppm to about 1500 ppm of zinc; and an amount of one or more molybdenum-containing compound(s) to provide from about 5 ppmw to about 300 ppmw molybdenum, and the one or more molybdenum-containing compound(s) is selected from the group consisting of molybdenum dithiocarbamates, molybdenum phosphorodithioates, organomolybdenum complexes, molybdenum dialkyldithiophosphates and mixtures thereof. The disclosure also relates to the compositions used in these methods.

The disclosure relates to methods of operating transmissions and for providing bearing pitting protection and a passing static friction performance according to Caterpillar TO-4 SEQ 1221 in a transmission including lubricating the transmission with a transmission fluid composition comprising: greater than 50 wt. % of a base oil of lubricating viscosity; an amount of one or more overbased calcium sulfonate detergent(s) to provide from about 2000 ppm to about 5000 ppm of calcium; an amount of one or more zinc dialkyl dithiophosphate compound(s) to provide from about 700 ppm to about 1500 ppm of zinc; and an amount of one or more molybdenum-containing compound(s) to provide from about 5 ppmw to about 300 ppmw molybdenum, and the one or more molybdenum-containing compound(s) is selected from the group consisting of molybdenum dithiocarbamates, molybdenum phosphorodithioates, organomolybdenum complexes, molybdenum dialkyldithiophosphates and mixtures thereof. The disclosure also relates to the compositions used in these methods.

A lubricating oil composition, a method of reducing low-speed pre-ignition (LSPI) in a direct-injected spark-ignited internal combustion engine, and a use of a lubricant composition to reduce LSPI events in such an engine. Preferably, the composition comprises a detergent package comprising a borated calcium detergent, wherein the detergent package provides a calcium content in the composition of at least 0.12 mass %, based on the total mass of the composition, and wherein the borated calcium detergent provides a boron content in the composition of at least 100 ppmm, based on the total mass of the composition. Optionally, the composition comprises a first detergent comprising a calcium detergent, and a second detergent comprising a borated calcium detergent.

A synthetic lubricant, cleaner and preservative composition and related methods for weapons and weapon systems, comprising: at least one isomer solvent; Alox 2100 calcium sulfonate; and at least one base oil selected from the base oil group consisting of: group I base oils; group II base oils; and group III base oils. Optional ingredients comprise mineral spirits, alpha-olefins, synthetic calcium sulfonates, fluoro-additives, and common moellen degras.

A synthetic lubricant, cleaner and preservative composition and related methods for weapons and weapon systems, comprising: at least one isomer solvent; Alox 2100 calcium sulfonate; and at least one base oil selected from the base oil group consisting of: group I base oils; group II base oils; and group III base oils. Optional ingredients comprise mineral spirits, alpha-olefins, synthetic calcium sulfonates, fluoro-additives, and common moellen degras.

A method for producing a lubricant in producing an overbased calcium sulfonate, which is converted from the vaterite form into the calcite form and, finally, a calcium sulfonate grease is produced by heating the mixture. A lubricant may comprise at least one ester composition, calcium carbonate and at least one overbased alkylbenzene sulfonate. The basicity of the mixture is limited during the preparation of the overbased calcium sulfonate to a TBN of at most 550 mg KOH/g and during the conversion of the calcium sulfonate to a TBN of at most 450 mg KOH/g. Both the calcium sulfonate and the grease containing said calcium sulfonate may be produced exclusively on an ester basis, so that the end product does not contain any mineral oil and is therefore easily and completely biodegradable.