The present invention relates to the use of a lubricant composition comprising (i) at least one boron derivative; and (ii) at least one base oil, for preventing and/or reducing pre-ignition, in particular at low speed, in a vehicle engine, wherein said composition is used during at least one change interval without the addition of a new lubricant composition, the content of boron in the composition being between 150 ppm and 350 ppm by weight.

The present invention relates to the use of a lubricant composition comprising (i) at least one boron derivative; and (ii) at least one base oil, for preventing and/or reducing pre-ignition, in particular at low speed, in a vehicle engine, wherein said composition is used during at least one change interval without the addition of a new lubricant composition, the content of boron in the composition being between 150 ppm and 350 ppm by weight.

A transmission fluid composition contains a major amount of a lubricating oil basestock, and a minor amount of an additive package comprising: (i) a mixture comprising two or more phosphites and/or phosphates; (ii) one or more thioester compounds; (iii) a detergent comprising calcium salicylate; and (iv) a poly(alkylene amine)-based ashless dispersant endcapped with metallocene-catalyzed PAO arms. Such a transmission fluid may be used for controlling/reducing wear in at least partially electrically-powered transmissions and/or for cooling/insulating electrical/electronic components of at least partially electrically-powered drivetrains.

A transmission fluid composition contains a major amount of a lubricating oil basestock, and a minor amount of an additive package comprising: (i) a mixture comprising two or more phosphites and/or phosphates; (ii) one or more thioester compounds; (iii) a detergent comprising calcium salicylate; and (iv) a poly(alkylene amine)-based ashless dispersant endcapped with metallocene-catalyzed PAO arms. Such a transmission fluid may be used for controlling/reducing wear in at least partially electrically-powered transmissions and/or for cooling/insulating electrical/electronic components of at least partially electrically-powered drivetrains.

A product resulting from the reaction of at least: an alkali or alkaline earth metal hydroxybenzoate compound, optionally substituted by a hydrocarbyl group and optionally overbased, a boron compound, an amine component selected from: a quaternary ammonium salt, compounds including two or three amine functions, wherein at least one amine function is substituted by at least one hydrocarbyl group. A lubricant composition including this product. Use of this product as a lubricant for two-stroke marine engines and four-stroke marine engines, more preferably two-stroke marine engines.

A product resulting from the reaction of at least: an alkali or alkaline earth metal hydroxybenzoate compound, optionally substituted by a hydrocarbyl group and optionally overbased, a boron compound, an amine component selected from: a quaternary ammonium salt, compounds including two or three amine functions, wherein at least one amine function is substituted by at least one hydrocarbyl group. A lubricant composition including this product. Use of this product as a lubricant for two-stroke marine engines and four-stroke marine engines, more preferably two-stroke marine engines.

A product resulting from the reaction of at least: an alkali or alkaline earth metal hydroxybenzoate compound, optionally substituted by a hydrocarbyl group and optionally overbased, a boron compound, an amine component selected from a di-fatty-alkyl(ene) polyalkylamine composition including one or more polyalkylamines of formulae (I) or (II). A lubricant composition including this product. Use of this product as a lubricant for two-stroke marine engines and four-stroke marine engines, more preferably two-stroke marine engines.

A product resulting from the reaction of at least: an alkali or alkaline earth metal hydroxybenzoate compound, optionally substituted by a hydrocarbyl group and optionally overbased, a boron compound, an amine component selected from a di-fatty-alkyl(ene) polyalkylamine composition including one or more polyalkylamines of formulae (I) or (II). A lubricant composition including this product. Use of this product as a lubricant for two-stroke marine engines and four-stroke marine engines, more preferably two-stroke marine engines.

A lubricating oil composition including: a lubricant base oil; (A) a triazole metal deactivator in an amount of 0.005 to 0.03 mass % in terms of nitrogen on the basis of the total mass of the composition; and (B1) a succinimide compound represented by the following general formula (1) in an amount of 0.0005 to 0.02 mass % in terms of nitrogen on the basis of the total mass of the composition:

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wherein in the general formula (1), R.sup.1 and R.sup.2 each independently represent a hydrogen atom or a C1-36 linear or branched chain alkyl or alkenyl group, and at least one of R.sup.1 and R.sup.2 is a C8-36 linear or branched chain alkyl or alkenyl group, and n represents an integer of 1 to 10.

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.