| abstract |
The invention deals with viscosity improvers which are α-olefin polymers and are particularly useful in lubricating compositions comprising (A) a liquid α-olefin polymer having a number average molecular weight from about 2,000 to about 100,000 and having derived from α-olefins having from about 4 to about 30 carbon atoms, provided further that (A) has a bimodal molecular weight distribution having (i) a peak molecular weight maximum at 2,000 to 5,000 for a lower molecular weight component and (ii) a peak molecular weight maximum at 50,000 to 75,000 for a higher molecular weight component; (B) an oil of lubricating viscosity and (C) at least one member selected from the group consisting of a friction modifier, a sulfurized olefin, an ash-producing detergent and, an ashless dispersant. |