Which term describes the main load-bearing structure of the tire, made up of layers of rubber-coated nylon-cord fabric?

• A. Bead
• B. Sidewall
• C. Tread
• D. Carcass

Answer: (D)

The main load-bearing portion of a tire is the carcass. It consists of fabric plies—layers of cords such as nylon—that are embedded in rubber and form the tire’s flexible skeleton. This structure carries the vehicle’s weight and inflation pressure, shaping the tire and absorbing shocks as it deforms with the road. The bead is the reinforced edge that anchors the tire to the wheel, the sidewall provides lateral support and protects the carcass, and the tread is the outer rubber surface that contacts the ground and wears over time. Since the description specifies layers of rubber-coated nylon-cord fabric, that set of plies is the carcass.