These heavy-duty pneumatic casings are mounted on the powered axles of tractor-trailers, providing the traction necessary for hauling substantial loads. They are distinguished from steer tires, which guide the vehicle, and trailer tires, which support the non-powered axles of the trailer. A typical configuration involves four or more of these specialized tires on the tractor’s drive axles.
Essential for safe and efficient over-the-road transport, these components bear the brunt of the vehicle’s weight and power. Their robust construction and deep tread design are crucial for grip, stability, and braking performance, especially under challenging conditions such as inclement weather or steep grades. Developments in materials science and tire technology have led to significant improvements in durability, fuel efficiency, and load-carrying capacity over time.