Lubricating oil compositions

Abstract

The present disclosure generally relates to a lubricating oil composition comprising: a major amount of an oil of lubricating viscosity, one or more detergents comprising at least one alkylhydroxybenzoate compound, and an ashless sulfur compound. Also provided is a method of lubricating an engine with said lubricating oil composition.

What is claimed is: 
     
         1 . A lubricating oil composition comprising:
 (a) a major amount of an oil of lubricating viscosity;   (b) one or more detergents comprising at least one alkylhydroxybenzoate compound derived from isomerized normal alpha olefin (NAO) having from about 10 to about 40 carbon atoms; and   (c) an ashless sulfur compound, wherein the ashless sulfur compound is not a dithiocarbamate; and
 wherein the TBN of the alkylhydroxybenzoate compound is at least 600 mg KOH/gm on an actives basis. 
   
     
     
         2 . The lubricating oil composition of  claim 1  wherein the TBN of the alkylhydroxybenzoate compound is 600-800 mg KOH/gm on an actives basis. 
     
     
         3 . The lubricating oil composition as in  claim 1 , where one more detergent is an alkali or an alkali earth metal alkylhydroxybenzoate derived from an alkyl group with 20-28 carbon atoms. 
     
     
         4 . The lubricating oil composition of  claim 1 , wherein the isomerized normal alpha olefin has an isomerization level (I) of the normal alpha olefin of from about 0.1 to about 0.4. 
     
     
         5 . The lubricating oil composition of  claim 1 , wherein the alkylhydroxybenzoate detergent is a calcium alkylhydroxybenzoate derived from an isomerized NAO. 
     
     
         6 . The lubricating oil composition of  claim 1 , wherein the ashless sulfur compound is selected from sulfurized fatty esters, sulfurized olefins, thiadiazoles, sulfurized olefins, ashless dithiophosphates, sulfurized phenols, and phenothiazines. 
     
     
         7 . A method of lubricating an engine comprising lubricating said engine with a lubricating oil composition comprising:
 (a) a major amount of an oil of lubricating viscosity, and   (b) one or more detergents comprising at least one alkylhydroxybenzoate compound derived from isomerized normal alpha olefin (NAO) having from about 10 to about 40 carbon atoms; and   (c) an ashless sulfur compound, wherein the ashless sulfur compound is not a dithiocarbamate; and
 wherein the TBN of the alkylhydroxybenzoate compound is at least 600 mg KOH/gm on an actives basis. 
   
     
     
         8 . The method of  claim 7  wherein the TBN of the alkylhydroxybenzoate compound is 600-800 mgKOH/gm on an actives basis. 
     
     
         9 . The method of  claim 7  wherein the ashless sulfur compound is a sulfurized fatty esters, sulfurized olefins, thiadiazoles, sulfurized olefins, ashless dithiophosphates, sulfurized phenols, and phenothiazines, or combinations thereof. 
     
     
         10 . The method of  claim 7 , wherein one more detergent is an alkali or an alkali earth metal alkylhydroxybenzoate derived from an alkyl group with 20-28 carbon atoms. 
     
     
         11 . The method of  claim 7 , wherein the isomerized normal alpha olefin has an isomerization level (I) of the normal alpha olefin of from about 0.1 to about 0.4. 
     
     
         12 . The method of  claim 7 , wherein the alkylhydroxybenzoate detergent is a calcium alkylhydroxybenzoate derived from an isomerized NAO. 
     
     
         13 . The method of  claim 7 , wherein oxidation of the lubricating oil in an engine is reduced.