A cylinder lubricant having a BN determined according to the standard ASTM D-2896 greater than or equal to 15 milligrams of potash per gram of lubricant, including: one or more lubricant base oils for marine engines, at least one detergent based on alkali or alkaline-earth metals, overbased with metallic carbonate salts, at least one neutral detergent, one or more oil-soluble alkoxylated fatty amines, having a BN determined according to the standard ASTM D-2896 comprised between 100 and 600 milligrams of potash per gram, where the percentage by mass of alkoxylated fatty amines with respect to the total weight of lubricant is chosen such that the BN provided by these compounds represents a contribution comprised between 2 and 8 milligrams of potash per gram of lubricant, and where the BN provided by the metallic carbonate salts represents a contribution of at the most 65%.

A lubricating oil composition contains a lubricating base oil and components (A) to (D): (A) a primary amine; (B) a tertiary amine; (C) at least one of metal sulfonate, metal phenate and metal salicylate; and (D) at least one of acid phosphate and acid phosphite.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition includes greater than 50 wt. % of a base oil, an overbased detergent having a TBN greater than 225 mg KOH/g and a low-based/neutral detergent having a TBN up to 175 mg KOH/g. A total amount of calcium from the overbased and low-based/neutral detergent is greater than 1100 ppm to less than 2400 ppm by weight based on a total weight of the lubricating oil composition. The lubricating oil composition and method may be effective to reduce low-speed pre-ignition events in a boosted internal combustion engine lubricated with the lubricating oil composition relative to commercially available lubricating oil compositions.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition includes greater than 50 wt. % of a base oil, one or more overbased calcium-containing detergents having a TBN greater than 225 mg KOH/g and one or more magnesium-containing detergents. A total amount of calcium from the one or more overbased calcium-containing detergents is from 900 ppm to less than 2400 ppm by weight, and a total amount of magnesium from the one or more magnesium-containing detergents is from 50 ppm to 500 ppm by weight, both based on a total weight of the lubricating oil composition. The lubricating oil composition and the method of using it are effective to reduce low speed pre-ignition events in a boosted internal combustion engine lubricated with the lubricating oil composition.

A metal-free detergent and antioxidant additive comprising the reaction product of an acidic organic compound, a boron compound, a polyamine such as polyethylene imine, and optionally an alkoxylated amine and/or an alkoxylated amide, is provided. The additives of the present invention have higher TBN than similar compounds known in the art.

A metal-free detergent and antioxidant additive comprising the reaction product of an acidic organic compound, a boron compound, a polyamine such as polyethylene imine, and optionally an alkoxylated amine and/or an alkoxylated amide, is provided. The additives of the present invention have higher TBN than similar compounds known in the art.