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.

Disclosed herein is an overbased alkaline earth metal hydrocarbyl-substituted salicylate detergent comprising both carbonate and borate moieties and exhibiting the following characteristics: a basicity index of at least 3.8; a ratio of soap content to mass % boron is greater than 55 mmol/kg; a soap content of at least 330 mmol/kg; a TBN, measured according to ASTM D2896, of at least 220 mg KOH/g; and a mass ratio of borate to carbonate from 0.75 to 6.0, wherein the alkaline earth metal comprises calcium and/or magnesium, and the hydrocarbyl substitution comprises 9 to 30 carbon atoms. Methods of making the boron-containing salicylate detergent, specifically to be package-stable, are also disclosed, as well as package-stable lubricant additive package concentrates and lubricating oil compositions containing same.

Lubricating compositions comprising an azole-acrylic adduct formed by contacting an azole compound with an acrylic. The adduct formed has at least one N-alkyl group comprising at least one acyl. The lubricating composition also comprises a thiadiazole. Methods of lubricating a component of a farm tractor, off-highway vehicle or drivetrain comprising contacting the component with the lubricating composition comprising an azole-acrylic adduct formed by mixing an azole compound with an acrylic. Methods of reducing corrosion in a component. The use of an azole-acrylic adduct in a lubricating composition to reduce corrosion in a component.

Embodiments of the present disclosure generally relate to diluent oils for viscosity modifiers and additive packages. Embodiments of the present disclosure also generally relate to lubricating oil compositions that include viscosity modifier concentrates and lubricating oil compositions that include additive package concentrates. Improved diluent oils capable of conveniently and cost effectively improving overall lubricant performance are provided.

An environmentally-improved motor oil blend and related methods for properly lubricating components of an engine and favorably modifying a plastic response of components of the engine, the blend being free of zinc di-alkyl-di-thiophosphates (ZDDP) and free of zinc di-thiophosphate (ZDTP), comprising: a motor oil selected from the motor oil group consisting of Group I, Group II, Group III, Group IV, and Group V motor oils; a motor oil additive comprising alpha-olefins and hydroisomerized hydro-treated severe hydrocracked base oil; ZDDP omitted from the chemical constituents of the motor oil; and ZDTP omitted from the chemical constituents of the motor oil.

Lubricating oil compositions may include a base oil, a succinimide compound, and a thioheterocyclic compound. Such compositions may have a sulfur content of 0.10 mass % to 1.00 mass % based on a total amount of the composition. A phosphorus content represented by P in mass % and a sulfated ash content represented by M in mass %, based on the total amount of such compositions, may satisfy any of conditions A to C: condition A: P<0.03, and M<0.3; condition B: P<0.03 and 0.3≦M≦0.6; and condition C: 0.03≦P≦0.06 and M<0.3.

[Technical Problem] An object is to provide a sliding system which can drastically reduce the friction coefficient on a sliding portion by means of a novel combination of a chromium nitride film and a lubricant oil. [Solution to Problem] The sliding system according to the present invention includes: a pair of sliding members having sliding surfaces that can relatively move while facing each other; and a lubricant oil that can be interposed between the sliding surfaces facing each other. At least one of the sliding surfaces is formed as a coating surface of a chromium nitride film, and the lubricant oil contains an oil-soluble molybdenum compound that has a chemical structure of a trinuclear of Mo. When the chromium nitride film as a whole is 100 at % (referred simply to as “%”), the chromium nitride film contains 40-65% of Cr and 35-55% of N, and the chromium nitride film has a relative surface area of 15-60% wherein the relative surface area is a surface area ratio of (111) plane to (200) plane obtained when analyzed using X-ray diffraction. The lubricant oil preferably contains 5-800 ppm of the oil-soluble molybdenum compound in a content mass of Mo to the lubricant oil as a whole.

A process for producing naphthenic base oils from low quality naphthenic crude feedstocks. The naphthenic base oils produced by the process have improved low temperature properties at high yields based on feedstock.

The invention provides a lubricating composition containing an aromatic compound and an oil of lubricating viscosity. The invention further relates to the use of the lubricating composition in an internal combustion engine. The invention further relates to the use of the aromatic compound as an antiwear agent.

The present disclosure describes transmission fluid compositions, additive packages, and methods for lubricating a transmission, particularly transmission fluid compositions having color stability that are able to meet or exceed vehicle transmission fluid specifications for different makes of vehicles. The transmission fluid composition contains a base oil and an additive composition having at least one thiadiazole compound the selected from compounds of the Formulas (I)-(II):

##STR00001##

wherein n is 1-5; R.sup.1 is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms; and R.sup.2 is a hydrogen or is a substituted or unsubstituted hydrocarbyl group having 1-100 carbon atoms, wherein the transmission fluid composition is adapted for use in a transmission.