| abstract |
This invention relates to lubricating oils containing certain ashless dispersants comprising an oil soluble polymeric hydrocarbon backbone having functional groups in which the hydrocarbon backbone is derived from an ethylene alpha-olefin (EAO) copolymer or alpha-olefin homo- or copolymer having > 30 % of terminal vinylidene unsaturation and an Mn of from 500 to 7000, in combination with overbased alkali metal additives. It particularly concerns crankcase lubricants having excellent properties of sludge and varnish control, giving good engine cleanliness and yet resistant to oxidation and/or with reduced tendency to thickening due to interactions in the package. |