Power transmission fluids with enhanced anti-shudder characteristics

摘要

A power transmission fluid composition having improved characteristics. The fluid may comprise a base oil and an additive composition including a viscosity index improving amount of a polyisoalkylene component having a molecular weight ranging from about 300 to about 3000 weight average molecular weight as determined by gel permeation chromatography. The power transmission fluid exhibits a kinematic viscosity (KV at 100° C.) of less than about 9 centistokes and a Brookfield viscosity (BV at -40° C.) of less than about 30,000 centipoise. Also the friction versus velocity curve for the fluid has a more positive slope at high speeds compared to similar fluids in the absence of the polyisoalkylene component.