Dayco Poly-V Belt

Dayco Poly-V Belt sizes are determined by the number of ribs and the belt length in millimeters, which you can find in your vehicle's service manual or by checking the old belt's part number. You can also use Dayco's online catalog or an auto parts store lookup tool by entering your vehicle's year, make, model, and engine size.

Dayco Poly-V belts generally last between 60,000 and 100,000 miles under normal driving conditions, though this varies based on climate, driving habits, and engine load. Signs of wear include squealing noises, visible cracking on the ribbed side, or glazing on the belt surface.

A Dayco Poly-V Belt (also called a serpentine or multi-rib belt) has multiple longitudinal ribs that provide greater contact surface area and can drive multiple accessories from a single belt. A standard V-belt has a single V-shaped cross-section and typically drives only one accessory per belt.

Most DIY mechanics can replace a Dayco Poly-V Belt using a socket wrench or breaker bar to release tension on the spring-loaded belt tensioner pulley. You should diagram or photograph the belt routing before removal, as the serpentine belt path around multiple pulleys can be complex.