Serpentine Belt

Silverado, sierra. 3.0l diesel. Allows for the operation of various pulleys, and drive belt accessories, with the use of a single belt Creates a secure point of contact with the pulley, which allows for traction Original equipment parts are designed to work with your GM vehicle safety systems -- aftermarket replacement parts may not meet the same OE safety regulations, depending on the part type

Tensioner

Silverado, sierra. 3.0l diesel. Helps keep drive belt at correct tension to help maintain proper function