Patent classifications
C10M2209/112
ADDITIVE PACKAGE AND LUBRICATING OIL COMPOSITION
An additive package is disclosed for preparing an automotive crankcase lubricating oil composition for an internal combustion engine. The additive package is made by admixing: (i) 50 mass % or less of an oil of lubricating viscosity; (ii) 50 mass % or less of at least one overbased metal detergent, preferably at least one overbased metal hydroxybenzoate detergent; (iii) 50 mass % or less of an oil-soluble block or graft co-polymer of at to least one polymeric block A which is derived from a hydroxycarboxylic acid and at least one polyalkylene block B which is a residue of a polyalkylene glycol, and (iv) optionally, at least one further additive selected from a dispersant, an antioxidant and/or an antiwear agent.
The additive package includes less than 2.00 mass % preferably less than 1.50 mass %, of a friction modifier which is a monoester of a C.sub.5 to C.sub.30 carboxylic acid and which is free of nitrogen.
Component (ii) is preferably an overbased metal hydroxybenzoate detergent.
Component (iii) acts as a friction modifier and can be used as a replacement for a friction modifier such as glycerol monooleate.
The additive package exhibits improved stability.
LUBRICATING COMPOSITION
A lubricating composition for use in the crankcase of an engine comprising (i) a base oil; (ii) one or more organo-molybdenum compounds at a level sufficient to provide from 100 to 1000 ppmw of molybdenum; and (iii) from 0.2 wt % to 5.0 wt %, by weight of the lubricating composition, of one or more organic polymeric friction reducing additives, wherein the one or more organic polymeric friction reducing additives has a molecular weight ranging from 1000 to 30000 Daltons and is the reaction product of: a) a hydrophobic polymeric sub unit which comprises a hydrophobic polymer selected from polyolefins, polyacrylics and polystyrenyls; b) a hydrophilic polymeric sub unit which comprises a hydrophilic polymer selected from polyethers, polyesters, polyamides; c) optionally at least one backbone moiety capable of linking together polymeric sub units; and d) optionally a chain terminating group. The lubricating composition provides improvements in terms of reduced friction and wear, in addition to improved fuel economy performance.