Carcass of A Tire

The carcass is the entire tire structure except the sidewall and tread. The carcass is made up of layers of cord materials such as rayon, nylon, polyester, fiber glass, or steel wire strands. The cords are laid parallel in layers and impregnated with rubber to form plies. The foundation of a tire is a strong but resilient fabric carcass made up of paired plies (or layers) of rubberized fibers called cords. Whatever material the fibers are - nylon, polyester, rayon, fiberglass, or steel strands - they must be identified under the "carcass cords" identification. Polyester does not "flat spot" after standing, as nylon does, causing temporarily bumpy rides; nor does it deteriorate when wet, as rayon can do. Fiberglass, while not as durable as steel, affords a smooth and quiet ride.