HIGH PERFORMANCE ENGINE OIL

High performance engine oils and other liquid lubricants comprise a liquid lubricant basestock of low viscosity from 1.5 to 12 cSt (110C) with two dissolved polymer components of differing molecular weights. The basestock i s preferably a single PAO or blend of PAOs with a co-basestock component which is preferably an ester or an alkylated aromatic of comparable viscosity. The lower molecular weight polymer is highly viscoelastic in character and is preferably an HVI-PAO; this component in the lubricant which provides unexpectedly high film thickness and unexpectedly good wear protection under conditions where the second, higher molecular weight polymer may lose some o r all of its thickening power. The use of the highly viscoelastic low molecula r weight polymer in combination with the higher molecular weight thickener enables the production of very widely cross-graded engine oils, especially oils with a low temperature grading of 0W or better. Oils with cross grading s of 0W20, 0W30, 0W40 or even more widely cross graded, for example 0W70 or higher may be achieved.