The use of berated dispersant, preferably in combination with polyalkylenyl succinic anhydrides, to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

The use of berated dispersant, preferably in combination with polyalkylenyl succinic anhydrides, to stabilise an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

The use of polyalkylenyl succinic anhydrides to stabilize an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

The use of polyalkylenyl succinic anhydrides to stabilize an additive concentrate which includes a salicylate detergent and a nitrogen-free ashless organic friction modifier.

A lubricating oil composition and method of operating a boosted internal combustion engine. The lubricating oil composition is formulated to be resistant to turbocharger deposit formation in the boosted internal combustion engine, as shown by its ability to ensure a TCO Temperature Increase of less than 9.0% as measured using the 2015 version of the General Motors dexos1® Turbocharger Coking Test. The lubricating oil composition may also have a low NOACK volatility, as measured by the method of ASTM D-5800 at 250° C.

Use of a guanidinium-based ionic liquid as detergent in a lubricant composition, notably for lubricating marine engines. A lubricant composition including a guanidinium-based ionic liquid.

Use of a guanidinium-based ionic liquid as detergent in a lubricant composition, notably for lubricating marine engines. A lubricant composition including a guanidinium-based ionic liquid.

A lubricating oil composition including: a lubricant base oil; (A) a calcium salicylate detergent in an amount of 0.005 to 0.03 mass % in terms of calcium on the basis of the total mass of the composition; and (B) a phosphite ester compound represented by the following general formula (1) in an amount of 0.01 to 0.06 mass % in terms of phosphorus on the basis of the total mass of the composition:

##STR00001##

wherein in the general formula (1), R.sup.1 and R.sup.2 are each independently a C5-20 group represented by the following general formula (2):

##STR00002##

wherein in the general formula (2), R.sup.3 is a C2-17 linear chain hydrocarbon group, and R.sup.4 is a C3-17 linear chain hydrocarbon group, and X.sup.1 is an oxygen atom or a sulfur atom.

A lubricating oil composition including: a lubricant base oil; (A) a calcium salicylate detergent in an amount of 0.005 to 0.03 mass % in terms of calcium on the basis of the total mass of the composition; and (B) a phosphite ester compound represented by the following general formula (1) in an amount of 0.01 to 0.06 mass % in terms of phosphorus on the basis of the total mass of the composition:

##STR00001##

wherein in the general formula (1), R.sup.1 and R.sup.2 are each independently a C5-20 group represented by the following general formula (2):

##STR00002##

wherein in the general formula (2), R.sup.3 is a C2-17 linear chain hydrocarbon group, and R.sup.4 is a C3-17 linear chain hydrocarbon group, and X.sup.1 is an oxygen atom or a sulfur atom.

Provided is a lubricating oil composition having a HTHS viscosity at 150° C. in a range of about 1.7 to about 3.2 mPa s and a low temperature cold cranking viscosity of less than 7,000 mPa s at −20° C., comprising: (a) a major amount of an oil of lubricating viscosity having a kinematic viscosity at 100° C. of from 3.5 mm.sup.2/s to 20 mm.sup.2/s and a viscosity index of greater than 120 with a sulfur content of less than 0.03 wt. %, are classified into the API group III, IV, or V base stock category, and have an aromatics content (C.sub.A) of less than 5%; (b) an organomolybdenum compound; (c) a dispersed hydrated alkali metal borate compound; (e) one or more dispersants; (f) one or more calcium-based metal detergents; and (g) optionally, one or more magnesium-based metal detergents. Also provided is a method for improving wear, high temperature detergency, and thermal stability in an engine comprising operating said engine with said lubricating oil composition.