A lubricant composition for a direct injected, boosted, spark ignited internal combustion engine that contains at least one potassium and/or lithium-containing compound is disclosed. This disclosure also relates to a method for preventing or reducing low speed pre-ignition in an engine lubricated with a formulated oil. The formulated oil has a composition comprising at least one oil soluble or oil dispersible potassium and/or lithium compound.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil includes greater than 50 wt. % of a base oil, one or more overbased calcium-containing detergents, one or more overbased magnesium-containing detergents and one or more molybdenum compounds and leads to a more than 60% reduction in LSPI compared to the LSPI of a reference oil and passes the Ball Rust Test. The ratio of wt % calcium from the overbased detergents to wt. % of magnesium from the overbased detergents is less than 11.9. A ratio of total ppm of magnesium to total TBN of the lubricating oil in mg KOH/g is greater than 19. A ratio of the total ppm of calcium to the total TBN of the lubricating oil is less than 222. The oil and method may reduce low-speed pre-ignition events in a boosted internal combustion relative to commercially available lubricating oils.

The lubricating oil composition for gas engine of the present invention contains (A) a base oil, (B1) an overbased calcium salicylate, (B2) an overbased sodium sulfonate, (C1) an amine-based antioxidant, and (C2) a phenol-based antioxidant, a total content of the amine-based antioxidant (C1) and the phenol-based antioxidant (C2) being 4 mass % or more on a basis of the whole amount of the composition.

An internal combustion engine crankcase lubricating oil composition having a sulphated ash content of no greater than 1.2 mass %, based on the mass of the lubricating oil composition, and a phosphorous content of no greater than 0.1 mass %, based on the mass of the lubricating oil composition, which lubricating oil composition comprises or is made by admixing: (A) a crankcase base oil of lubricating viscosity, in a major amount; and (B) the following additives, in respective minor amounts: (B1) a polymeric friction modifier being the reaction product of (a) a functionalized polyolefin, (b) a polyether, (c) a polyol, and (d) a monocarboxylic acid chain terminating group; and (B2) at least one oil-soluble molybdenum compound.

A method for improving fuel efficiency and reducing frictional properties while maintaining or improving deposit control, in an engine lubricated with a lubricating oil. The lubricating engine oil has a composition including from 75 to 95 wt % of lubricating oil base stock selected from the group consisting of a Group I base stock, a Group II base stock, a Group III base stock, a Group IV base stock, a Group V base stock and combinations thereof; a friction modifier mixture comprising a polymeric ethoxylated fatty acid ester having a molecular weight of greater than or equal to 2000 at from 0.1 to 1.0 wt. % and an organic molybdenum containing friction modifier contributing from 80 to 500 ppm of elemental molybdenum, and an overbased calcium salicylate detergent contributing from 200 to 2000 ppm of elemental calcium; and one or more other lubricating oil additives. The lubricating engine oils are useful in internal combustion engines including direct injection, gasoline and diesel engines.

Disclosed is a lubricating oil composition containing a base oil, a viscosity index improver, a molybdenum-based friction modifier, a boron-containing dispersant, and at least two extreme-pressure additives selected from a sulfur-based extreme-pressure additive, a phosphorous-based extreme-pressure additive and a sulfur/phosphorus-based extreme-pressure additive, or a sulfur/phosphorus-based extreme-pressure additive. The base oil is a synthetic oil having a kinematic viscosity at 100 C. of 3 mm.sup.2/s or more and 10 mm.sup.2/s or less, the viscosity index improver is a resin having a number average molecular weight (Mn) of 1,000 or more and 10,000 or less, the mass ratio of boron atoms (B) contained in the boron-containing dispersant to molybdenum atoms (Mo) contained in the molybdenum-based friction modifier, [(B)/(Mo)] is 1 or more and 5 or less, and the mass ratio of sulfur atoms (S) to phosphorus atoms (P) contained in the extreme-pressure additive(s), [(S)/(P)] is 10 or more and 20 or less.

Provided is a non-Newtonian engine oil lubricant composition with improved fuel efficiency and engine wear protection. The lubricant composition includes a major amount of a base oil including a Group II base stock and an optional Group V base stock, from 0.1 to 9.0 wt. % of at least one viscosity modifier and from 0.1 to 1.2 wt. % of at least one friction modifier. The non-Newtonian engine oil lubricant composition has a kinematic viscosity at 100 deg. C. of less than or equal to 10 cSt and an HTHS (ASTM D4683) of less than or equal to 2.2 cP at 150 C. Also provided are methods of using the lubricant composition in internal combustion engines and methods of making the lubricant composition.

The present patent application relates to a method for reducing wear and tear on mechanical parts that are in contact with each other in an internal combustion engine by using a lubricating composition comprising: at least one base oil; at least one oxothiomolybdate salt; and at least one anti-wear compound;
wherein at least one of the said parts includes a surface that comprises an amorphous carbon type coating.

A lubricating oil composition is provided. The composition includes major amount of an oil of lubricating viscosity, or more alkaline earth metal detergent, one or more nitrogen-containing dispersant, and up to about 0.10 wt % of zinc from zinc dithiophosphate. The lubricating oil composition has sulfur content of up to 0.10 wt %, sulfated ash content of up to 0.30 wt %, and the ratio of total nitrogen concentration to total alkaline earth metal concentration from the one or more alkaline earth metal detergent is about 20 or greater.

The present disclosure concerns a lubricant composition including: at least one base oil; and at least two glycerol esters E.sub.1 and E.sub.2, ester E.sub.1 being an ester of glycerol and of a C.sub.12-C.sub.26 carboxylic acid and ester E.sub.2 being an ester of glycerol and of a C.sub.4-C.sub.10 carboxylic acid. The lubricant composition has good friction properties, and the use thereof promotes fuel savings.