Radial vs. Bias Ply Tires

Feb 17, 2023 | Uncategorized

The following guide answers the question: What are radial vs. bias ply tires?

Whether you pull a utility trailer, livestock, car hauler, or enclosed trailer, having the right tires for your trailer is so important. When choosing trailer tires, the size, type of trailer, and weight of the tow load are the important factors that will help you choose which tires are best for your trailer. 

ST Tires (Speciality Tires)

Most trailers are equipped with ST tires because they are built for trailers with a stiffer sidewall to carry heavy loads. There are two types of ST tires – radial and bias ply tires. Both types of specialty tire designs have their advantages and disadvantages.

radial vs. bias ply tires

According to Treadworld, the difference between bias ply and radial ST tires starts with the way each tire is constructed. As illustrated in the graphic above, bias ply tires are manufactured with alternating diagonal plies of rubberized nylon or polyester, with fiberglass belts that strengthen both the tread and sidewall areas to enhance the overall load-carrying capacity and provide resistance to breaks. Even at low inflation, bias ply tires won’t have much sidewall bulge. Radial tires are constructed with overlapping polyester, then strengthened with steel mesh belts to stiffen, stabilize and fortify the tread.

Is radial or bias ply the best tire option for your trailer?

Radial tires features

  • Superior handling on paved roads and cornering
  • Better handling on roadway ruts and bumps
  • Punctures often result in a tear in the sidewall or tread
  • Ideal at higher towing speeds
  • Better at dissipating heat

Bias Ply features

  • Better for non-paved or uneven roadways
  • Sidewall puncture resistance
  • Better tread and sidewall support

Bias ply tires have a load-carrying advantage, but radial tires are built specifically for heavy loads. These tires tend to be less expensive than radial tires, and radial trailer tires tend to bounce and sway less for a smoother, quieter drive down the road. 

BlueSwift Axles is your trailer axle specialist

While there are no guarantees when it comes to the life expectancy of any part on your trailer, we recommend inspecting your trailer tires often to check for punctures, holes, or uneven tread. BlueSwift Axles specializes in trailer axle replacements and we manufacture axles with the American hauler in mind. We’re proud to provide quality parts to minimize downtime and get you back on the road quicker.