When it comes to commercial truck tires, the size and specification matter. To avoid unnecessary maintenance needs for your vehicle, you need to understand the exact type of tire it requires to operate as it should. There are many different elements that differentiate one commercial truck tire from another, and understanding each is the key to ensuring your fleet stays on the road and out of the shop. 

Click here to understand more about trucks because there are a lot of components of commercial truck tires that differ greatly from regular automotive vehicle tires. In fact, they have been built specifically to handle high amounts of weight, pressure, and velocity. They are durable and reliable tires that can hold their strength over thousands and thousands of miles before they are in need of a truck tire road service.

Understanding how these tires work is essential for maintaining safe driving habits as a trucker on the road. Here are a few things you should know about the truck tire and its many parts.

The Inner Layer

The innermost layer of a truck tire is known as the inner liner, which is put in place to hold in the tire’s air. It is typically made of synthetic rubber.

The Cords

The cords, also known as the carcass, is the frame that protects the inner liner and helps it keep its shape. This works to keep everything moving even under intense pressure.

The Bead

There is a thin layer of steel wire that connects the tire to the rim. This is known as the bead, and it is also integral to the structural support of the tire.

The Side

The side, or sidewall, is another important feature of the truck tire. You can find it between the outer tread and the bead, and it is made of crack-resistant rubber. It protects the carcass and the inner layer from any potential damage.


Breakers are belts that connect the main components of the tire, from the carcass to the tread. These belts are typically thick steel cords, which work to bind all of the layers together in a secure way. This also protects the tire from potential damage and keeps it going for miles and miles.

Tread and Under Tread

The two outermost layers – the tread and the under tread – are made from synthetic, and natural rubber blended for extra support and flexibility. The under tread keeps the tire cool when the truck is on the road, so it doesn’t overheat and burn up. The thread itself is the only part of the tire that touches the road. It contains a very thick tread and can keep going for tens of thousands of miles.

Understanding Commercial Truck Tire Specifications

Look at the sidewall of any commercial truck tire and you’ll see a series of numbers and letters. Each number and letter indicates a different characteristic fleet managers need to understand when selecting their commercial truck tires, including:

  1. Tire Type: The first letter in the series will either be a “P” or “LT.” An “LT” appearing at the end indicates tires specified for light truck use while a “C” appearing at the end indicates tires specified for commercial use.
  1. Cross-Sectional Width: The following three digits indicate the cross-sectional width of the tire in millimeters. The width measures from the widest point on the inner sidewall to the widest point on the outer sidewall.
  1. Aspect Ratio: This shows the sidewall’s distance from the wheel rim to the outside of the tread and is usually represented by two digits following the forward slash in the series.
  1. Construction: Tire construction is indicated by either an “R,” “D,” or “B.” “R” means the tire is a radial construction; “D” indicates a bias ply construction; and “B” shows a belted tire construction.
  1. Size & Diameter: The next two digits show the tire and wheel diameter in inches.