We are independent & ad-supported. We may earn a commission for purchases made through our links.
Advertiser Disclosure
Our website is an independent, advertising-supported platform. We provide our content free of charge to our readers, and to keep it that way, we rely on revenue generated through advertisements and affiliate partnerships. This means that when you click on certain links on our site and make a purchase, we may earn a commission. Learn more.
How We Make Money
We sustain our operations through affiliate commissions and advertising. If you click on an affiliate link and make a purchase, we may receive a commission from the merchant at no additional cost to you. We also display advertisements on our website, which help generate revenue to support our work and keep our content free for readers. Our editorial team operates independently of our advertising and affiliate partnerships to ensure that our content remains unbiased and focused on providing you with the best information and recommendations based on thorough research and honest evaluations. To remain transparent, we’ve provided a list of our current affiliate partners here.

What are Radial Tires?

By R. Kayne
Updated May 23, 2024
Our promise to you
WikiMotors is dedicated to creating trustworthy, high-quality content that always prioritizes transparency, integrity, and inclusivity above all else. Our ensure that our content creation and review process includes rigorous fact-checking, evidence-based, and continual updates to ensure accuracy and reliability.

Our Promise to you

Founded in 2002, our company has been a trusted resource for readers seeking informative and engaging content. Our dedication to quality remains unwavering—and will never change. We follow a strict editorial policy, ensuring that our content is authored by highly qualified professionals and edited by subject matter experts. This guarantees that everything we publish is objective, accurate, and trustworthy.

Over the years, we've refined our approach to cover a wide range of topics, providing readers with reliable and practical advice to enhance their knowledge and skills. That's why millions of readers turn to us each year. Join us in celebrating the joy of learning, guided by standards you can trust.

Editorial Standards

At WikiMotors, we are committed to creating content that you can trust. Our editorial process is designed to ensure that every piece of content we publish is accurate, reliable, and informative.

Our team of experienced writers and editors follows a strict set of guidelines to ensure the highest quality content. We conduct thorough research, fact-check all information, and rely on credible sources to back up our claims. Our content is reviewed by subject-matter experts to ensure accuracy and clarity.

We believe in transparency and maintain editorial independence from our advertisers. Our team does not receive direct compensation from advertisers, allowing us to create unbiased content that prioritizes your interests.

Radial tires differ from traditional diagonal bias-ply tires in their construction, which minimizes tread wear and improves flexibility of the sidewall for better handling. They contain belts of steel fibers that go around the circumference, which helps stabilize the tire.

While tires may look simple, they are actually made up of a series of layers of different materials. If someone peeled back the tread in bias-ply tire, he would see a nylon weave (these are the plies) beneath, running in a diagonal pattern and meeting in the centerline of the face of the tire. The weave runs at an angle down the sidewalls to the bead, the part of the tire that fits on the wheel's rim. Nylon ply is stronger than polyester but compresses and sets when under load, especially when left for periods of time, resulting in "flat areas" on the tire. Due to the direction the ply runs on these tires, the sidewalls don't bulge even if the tire is low. This design allows the tread to wrap down over the sidewall because there is no transition point from the circumferential face to the sidewall.

A radial tire is constructed differently. Rather than diagonal nylon plies that meet in the centerline, it's made with polyester cords that run perpendicular from bead to bead, up over the face of the tire and down each sidewall. In other words, it's "wrapped" at a right-angle to the direction of the tread.

On the face of the tire over the polyester wrap is a belt that runs below the tread. The belt is nearly the width of the tire and runs around the circumference, giving the tire a "squared" look. Though belts used to be made of rubber-coated fibers, nearly all belts today are made from steel fibers, leading to name "steel-belted" radial. This belt helps stabilize the tread, reducing wear. Because of the construction of the tire, the sidewall will always have a bulge at the point of contact, and as a result, some people may think that they are under inflated.

The average steel-belted radial gets about 100,000 miles (161,000 km) of wear, while the bias-ply tires are generally rated at about 30,000 miles (48,280 km). By reading the model number on the sidewall of any tire, a car owner can quickly see what type of tire he has, though most radial tires include the word "radial" in the model name. There are several symbols used to decode a common tire, such as the P205/65R15:

  • P — stands for passenger (LT would mean light truck)
  • 205 — indicates width in millimeters
  • 65 — refers to the aspect ratio, or how tall the tire is compared to how wide it is; in this example, the tire height is 65% of its width
  • R — radial ("D" here would indicate diagonal bias ply)
  • 15 — the diameter of the tire in inches

The tire might also have other designations like XL or RF, which indicates Extra Load or Reinforced respectively. It might also have tread type or other codes included. Most of the tires on the road today are steel-belted radial tires.

WikiMotors is dedicated to providing accurate and trustworthy information. We carefully select reputable sources and employ a rigorous fact-checking process to maintain the highest standards. To learn more about our commitment to accuracy, read our editorial process.
Discussion Comments
By anon87968 — On Jun 02, 2010

I want to purchase 4 sets of radial tires, tubes and flaps of the following technical specifications: Brand: Bridgestone/yokohama/hino/dunlop; Technical specifications: 14R24, 385/95R24-170E.

I couldn't find the tires and i'm in dire need. Please help me out.

By anon71468 — On Mar 18, 2010

I have had a tire that the belts let go on the inside and it was indeed distorted on the outside so someone is misinformed.

By anon56705 — On Dec 16, 2009

first let me say i made steel belts for 25 years. Hauling a pick up is not going to shift a belt; the tread is too thick. Unless they were under-inflated and hauled for a long period of time, no damage to belt is possible. look for a bent rim or have the tires balanced.

By anon55427 — On Dec 07, 2009

I was going to sell two used steel belted LT tires and the potential buyer said he could tell the steel belts were broken inside the tire because of the irregularities on the outside of the tire.

The tire shop said that was not possible without disassembling the tire. Any ideas?

By anon27554 — On Mar 02, 2009

Can someone tell me if radial tires were big in the mid 70's (big as in fad not in size) and if so

is there a way I can find a price of a tire back in late 1974 early 1975, just in general, size and make no idea (mid to big size car)...

Thanks It's important...

By suwhitfield — On Dec 11, 2007

If a vehicle with steel belted radial tires is towed by a tow truck hauling the vehicle backward will it damage the tires? Our chevy pickup was towed and now it has a severe vibration in the front. I have been told you cannot pull radial tires backward - could this be true?

WikiMotors, in your inbox

Our latest articles, guides, and more, delivered daily.

WikiMotors, in your inbox

Our latest articles, guides, and more, delivered daily.