A tread additive composition to be combined with a base composition for tire treads to achieve low rolling resistance includes an elastomeric component, a first additive component, and a second additive component. The elastomeric component includes a first silane-grafted polyolefine elastomer. The first additive component including a polymer carrier, a reinforcing filler, silane-terminated liquid polybutadienes, and one or more process activators. The second additive component including a butadiene rubber, a hydrocarbon resin, sulfur; and one or more accelerators. Advantageously, the tread additive composition can decrease rolling resistance and improve fuel economy when combined with a base tread composition as compared to treads formed from the base tread composition without the tread additive composition.