Lubricating Oil Composition

Abstract

SAE 0W and SAE 5W multigrade crankcase lubricating oil compositions for heavy duty diesel (HDD) engines meeting the performance requirements of at least one of the API CJ-4; API-CI-4, and/or ACEA A7 specifications, having a sulfated ash content of no greater than 1.0 mass %, a sulfur content of no greater than 0.4 mass %, and a phosphorus content of no greater than 0.12 mass %, formulated with a major amount of oil of lubricating viscosity including less than about 30 mass %, based on the total mass of oil of lubricating viscosity, of Group IV and/or Group V base stock, at least 0.3 mass %, of a non-hydrogenated olefin polymer; and greater than about 40 ppm, of boron.

1 . An SAE 0W or 5W multigrade lubricating oil composition having a sulfated ash content of no greater than 0.1 mass %, a sulfur content of no greater than 0.4 mass %, and a phosphorus content of no greater than 0.12 mass % and meeting the wear performance requirements of at least one of API CJ-4; API CI-4; and ACEA E7, said lubricating oil composition comprising:
 (a) a major amount of oil of lubricating viscosity wherein said oil of lubricating viscosity comprises no greater than about 30 mass % of one or more Group IV base stock and/or Group V base stock;   (b) at least about 0.3 mass % of a non-hydrogenated olefin polymer; and   (c) at least 40 ppm of boron.   
     
     
         2 . A lubricating oil composition, as claimed in  claim 1 , wherein said oil of lubricating viscosity comprises no greater than about 10 mass % of one or more Group IV base stock and/or Group V base stock. 
     
     
         3 . A lubricating oil composition, as claimed in  claim 1 , wherein said oil of lubricating viscosity consists essentially of Group III base stock. 
     
     
         4 . A lubricating oil composition, as claimed in  claim 1 , having a sulfated ash content of from about 0.7 to about 1.0 mass %. 
     
     
         5 . A lubricating oil composition, as claimed in  claim 1 , having a phosphorus content of from about 0.08 to about 0.12 mass %. 
     
     
         6 . A lubricating oil composition, as claimed in  claim 1 , comprising from about 0.3 to about 5 mass % of said non-hydrogenated olefin polymer. 
     
     
         7 . A lubricating oil composition, as claimed in  claim 1 , comprising from about 0.5 to about 5.0 mass % of said non-hydrogenated olefin polymer. 
     
     
         8 . A lubricating oil composition, as claimed in  claim 1 , wherein said non-hydrogenated olefin polymer is selected from polybutene, polylsobutene and mixtures thereof. 
     
     
         9 . A lubricating oil composition, as claimed in  claim 8 , wherein said non-hydrogenated olefin polymer has a number average molecular weight of from about 450 to about 2300. 
     
     
         10 . A lubricating oil composition, as claimed in  claim 1 , containing from about 40 to about 600 ppm of boron. 
     
     
         11 . A lubricating oil composition, as claimed in  claim 10 , containing from about 50 to about 100 ppm of boron. 
     
     
         12 . A lubricating oil composition, as claimed in  claim 1 , further comprising one or more metal detergents including a magnesium detergent in an amount providing said composition with at least about 0.09 mass % of magnesium. 
     
     
         13 . A lubricating oil composition, as claimed in  claim 12 , wherein said magnesium detergent provides said composition with at least about 0.115 mass % of magnesium. 
     
     
         14 . A lubricating oil composition, as claimed in  claim 1 , having a TBN of from 7 to about 15. 
     
     
         15 . A lubricating oil composition, as claimed in  claim 1 , further comprising a molybdenum compound in an amount providing said composition with from about 10 to about 350 ppm of molybdenum. 
     
     
         16 . A lubricating oil composition, as claimed in  claim 1 , further comprising at least about 0.5 mass % of an ashless antioxidant selected from the group consisting of sulfur-free phenolic antioxidants, aminic antioxidants, and mixtures thereof. 
     
     
         17 . A lubricating oil composition, as claimed in  claim 1 , further comprising at least one nitrogen-containing dispersant, in an amount providing said lubricating oil composition with at least 0.08 mass % of nitrogen. 
     
     
         18 . A lubricating oil composition, as claimed in  claim 17 , wherein said nitrogen-containing dispersant comprises at least one dispersant derived from highly reactive polyisobutylene. 
     
     
         19 . A lubricating oil composition, as claimed in  claim 1 , further comprising a minor amount of at least one soot dispersing compound of the formula: 
       
         
           
           
               
               
           
         
         where each Ar independently represents an aromatic moiety having 0 to 3 substituents selected from alkyl, alkoxy, alkoxyalkyl, hydroxy, hydroxyalkyl, acyloxy, acyloxyalkyl, aryloxy, aryloxy alkyl, halo and combinations thereof; each L is independently a linking moiety comprising a carbon-carbon single bond or a linking group; each Y′ is independently a moiety of the formula Z(O(CR 2 ) n ) y X—, where X is selected from (CR′ 2 ) z , O and S; R and R′ are each independently selected from H, C 1  to C 6  alkyl and aryl; z is 1 to 10; n is 0 to 10 when X is (CR′ 2 ) z , and 2 to 10 when X is O or S; y is 1 to 30; Z is H, an acyl group, an alkyl group or an aryl group; each a is independently 0 to 3, at least one Ar moiety bears at least one group Y in which Z is not H; and m is 1 to 100. 
       
     
     
         20 . A lubricating oil composition, as claimed in  claim 1 , further comprising a minor amount of a linear block copolymer comprising one block derived primarily from vinyl aromatic hydrocarbon monomer, and one block derived primarily from diene monomer. 
     
     
         21 . An SAE 0W or 5W multigrade lubricating oil composition having a sulfated ash content of no greater than 0.1 mass %, a sulfur content of no greater than 0.4 mass %, and a phosphorus content of from about 0.08 to 0.12 mass %; and a TBN of from about 7 to about 15 and meeting the wear performance requirements of at least one of API CJ-4, API CI-4, and ACEA E7, said lubricating oil composition comprising:
 (a) a major amount of oil of lubricating viscosity wherein said oil of lubricating viscosity comprises no greater than about 10 mass % of one or more Group IV base stock and/or Group V base stock;   (b) 0.3 to about 5.0 mass % of a non-hydrogenated olefin polymer having a number average molecular weight of from about 450 to about 2300, selected from the group consisting of polybutene, polylsobutene and mixtures thereof;   (c) an amount of an overbased magnesium detergent providing said lubricating oil composition with at least 0.09 mass % of magnesium;   (c) at least 0.5 mass % of an ashless antioxidant selected from the group consisting of sulfur-free phenolic antioxidants, aminic antioxidants, and mixtures thereof;   (d) at least one nitrogen-containing dispersant, in an amount providing said lubricating oil composition with at least 0.08 mass % of nitrogen; and   (e) a molybdenum compound in an amount providing said lubricating oil composition with from about 10 to about 350 ppm of molybdenum;   wherein said lubricating oil composition has a boron content of from about 50 to about 100 ppm.   
     
     
         22 . A lubricating oil composition, as claimed in  claim 21 , wherein said oil of lubricating viscosity consists essentially of Group III base stock. 
     
     
         23 . A lubricating oil composition, as claimed in  claim 21 , further comprising a minor amount of at least one soot dispersing compound of the formula: 
       
         
           
           
               
               
           
         
         where each Ar independently represents an aromatic moiety having 0 to 3 substituents selected from alkyl, alkoxy, alkoxyalkyl, hydroxy, hydroxyalkyl, acyloxy, acyloxyalkyl, aryloxy, aryloxy alkyl, halo and combinations thereof; each L is independently a linking moiety comprising a carbon-carbon single bond or a linking group; each Y′ is independently a moiety of the formula Z(O(CR 2 ) n ) y X—, where X is selected from (CR′ 2 ) z , O and S; R and R′ are each independently selected from H, C 1  to C 6  alkyl and aryl; z is 1 to 10; n is 0 to 10 when X is (CR′ 2 ) z , and 2 to 10 when X is O or S; y is 1 to 30; Z is H, an acyl group, an alkyl group or an aryl group; each a is independently 0 to 3, at least one Ar moiety bears at least one group Y in which Z is not H; and m is 1 to 100. 
       
     
     
         24 . A lubricating oil composition, as claimed in  claim 21 , further comprising a minor amount of a linear block copolymer comprising one block derived primarily from vinyl aromatic hydrocarbon monomer, and one block derived primarily from diene monomer. 
     
     
         25 . A heavy duty diesel (HDD) engine lubricated with a lubricating oil composition as claimed in  claim 1 . 
     
     
         26 . A heavy duty diesel (HDD) engine lubricated with a lubricating oil composition as claimed in  claim 21 . 
     
     
         27 . A method for improving the wear performance of a heavy duty diesel (HDD) engine, which method comprises the steps of lubricating the engine with a lubricating oil composition, as claimed in  claim 1 , and operating the lubricated engine. 
     
     
         28 . A method for improving the wear performance of a heavy duty diesel (HDD) engine, which method comprises the steps of lubricating the engine with a lubricating oil composition, as claimed in  claim 21 , and operating the lubricated engine.