Tires are available with different types of tread design suitable for various applications.

Deep Lugs improve traction at the expense of higher rolling resistance. Shallow Lugs reduce the tread depth to decrease rolling resistance. Ribs sacrifice traction but offer lower rolling resistance and better fuel economy.

In addition, there are tall tires (11R24.5), low profile tires (285/75R24.5), and wide base / super single tires (445/50R22.5). The tall tires exhibit a little more rolling resistance because of the increased flex of the taller sidewall. Low profile tires have a weight advantage and less rolling resistance. The super single tires can provide up to an 800-pound advantage over duals on the tractor alone. A similar weight saving can be realized on the trailer. The super single tires offer the least rolling resistance. In actual application, one can expect an approximate 3 - 4% improvement in fuel economy with super singles installed on both the tractor and the trailer.

Some facts to consider:

• All tires are at their least fuel-efficient point when new. As the new tire wears, the rolling resistance decreases and fuel economy improves.
• The majority of the fuel economy advantage is obtained when the tread is 50% worn.
• Regular radial tires and fuel economy labeled tires provide nearly the same fuel economy as they approach wear out.
• Above 45 mph, air resistance/aerodynamics is a more important consideration than tire rolling resistance.
• Fuel-efficient tires loose half of their fuel efficiency benefit when vehicle speed increases from 60 to 75 mph.
• Retreads are nearly equal to new tires in rolling resistance.