The present invention relates to lubricant compositions for scooter engines and methods for reducing static friction between ferrous and non-ferrous surfaces as may be found in a wet clutch. The lubricant compositions contain polyether compounds in combination with one or more ash-free friction modifiers.

A lubricating oil composition for internal combustion engines is disclosed. The composition exhibits a lower coefficient of friction and improved cleaning properties without causing a deterioration in thermal and oxidation stability.

A lubricant composition includes a base oil and an additive package. The additive package includes a seal compatibility additive chosen from a halide seal compatibility additive, an epoxide seal compatibility additive, a boroxine seal compatibility additive, a sulfonate ester seal compatibility additive, and combinations thereof. The alkoxylated amide and the ester are set forth in general formulas A and B, respectively: In general formulas A and B, each R.sup.13, R.sup.II, R.sup.III, and R.sup.IV, is, independently, a linear or branched, saturated or unsaturated, hydrocarbyl group. In addition, at least one of R.sup.II and R.sup.III include an alkoxy group, and R.sup.IV includes an amine group.

##STR00001##

The invention provides a lubricant composition containing an oil of lubricating viscosity and a boron-containing compound, wherein the boron containing compound comprises a borate ester comprising at least one alkyl group having a branch at the ? position or higher. The invention further relates to a method of lubricating an internal combustion engine with the lubricant composition.

A fully-formulating lubricating composition comprising an oil of lubricating viscosity; an ionic tetrahedral borate compound including a tetrahedral borate anion having a boron atom with two bidentate di-oxo ligands both being a linear C18-tartrimide; a first dispersant comprising a conventional ammonium substituted polyisobutenyl succinimide compound having a polyisobutenyl number average molecular weight of 750 to 2,500; a second dispersant comprising an ammonium substituted polyisobutenyl succinimde compound having an N:CO ratio of 1.8 and a polyisobutylenyl number average molecular weight of 750 to 2,500, wherein one or more of the first dispersant and the second dispersant are in cationic form. The fully formulated lubricating composition including one or more performance additives.

A zinc free or substantially zinc free lubricant having a sulfated ash content of less than about 1.0 percent and including (a) an oil of lubricating viscosity; (b) 0.03 to about 3.0 weight percent of a phosphite compound; (c) an metal containing detergent; (d) a polyisobutylene succinimide dispersant derived from an ethylene polyamine and having a carbonyl to nitrogen ratio equal or greater than 1; (e) at least one other dispersant; (f) a boron containing compound in amount to provide at least 25 ppm boron to the lubricant composition is useful for inhibiting siloxane deposits in a stationary gas engine fueled by natural gas having a high silicon concentration.

A lubricating oil composition including greater than 50 wt. % of a base oil; a reaction product of a hydrocarbyl acid phosphate and a nitrogen containing compound; and an oil soluble hydrocarbyl borate. A method for reducing gear scuffing in a transmission including a step of lubricating the transmission with the above-mentioned lubricating oil composition and a method of operating a transmission including steps of lubricating said transmission with the lubricating oil composition described above and operating the transmission, are also described.

A composition of an oil-soluble ionic detergent that does not contribute metal ions to the composition, and which comprises a quaternary non-metallic pnictogen cation and an organic anion having at least one hydrocarbyl group of sufficient length to impart oil solubility to the detergent, the detergent having a total base number (TBN) to total acid number (TAN) ratio of at least 2:1 imparts ash-free basicity to a lubricant composition.

A composition of an oil-soluble ionic detergent that does not contribute metal ions to the composition, and which comprises a quaternary non-metallic pnictogen cation and an organic anion having at least one hydrocarbyl group of sufficient length to impart oil solubility to the detergent, the detergent having a total base number (TBN) to total acid number (TAN) ratio of at least 2:1 imparts ash-free basicity to a lubricant composition.

An additive for a lubricating composition includes an ionic tetrahedral borate compound which includes a cation and a tetrahedral borate anion having a boron atom, the boron atom has at least one aliphatic bidentate di-oxo ligand. The cation may be selected to provide detergent and/or dispersant and/or antioxidant properties to a lubricating composition.