Your tires are the only part of your vehicle that touches the ground, whether you're driving fast or tackling tough obstacles. It's important to understand what makes each tire unique, so you can choose the right one for your vehicle, favorite trails, and the climate where you'll be riding.
We'll explain the tire sidewall and its markings, which can be confusing at first. For this post, we're using the Toyo Open Country SxS as an example. The sidewall gives you important details about the tire's purpose, size, load capacity, and how it handles heat and speed.
Tire Size: 32X9.50R15 LT
- 32x - Tire height
- 9.50 - Tire width
- R - Radial construction
- 15 - Wheel diameter
- LT - Light Truck
Tire diameter means the total height of the tire. For SxS tires, this measurement is always in inches and is usually what people mention when talking about tire size.
Tire width refers to the width of the tire'sTire width is the measurement of the tire's contact patch or aspect ratio. This matters if you have limits on how wide your vehicle can be, like fitting in a trailer or garage. For SxS tires, 9 to 10 inches is a common width.
R, or plies, run perpendicular to the direction of travel, and belts under the tread. This gives them a smoother ride and helps prevent heat build-up, which can make the tires last longer. If your tire is not Radial, you have bias-ply tires, which are built with plies that are layered so they crisscross. This creates a more rugged design, with greater puncture resistance in the sidewall.
Wheel diameter is the size of the wheel that fits the tire. In this case, a 15-inch wheel is made to match this tire size. SxS wheels are usually 7 inches wide, so a 15x7-inch wheel is ideal for this tire.
Light Truck (LT) tires are built with a rugged carcass, including more, thicker plies and sidewall reinforcements. Because LT tires come with higher load-carrying capacities and a more robust construction, they’re far more rugged and durable than your average passenger tire, making them perfect for extra weight and tough road conditions.
Max load 625kg (1820 lbs) at 250 kPa (35 psi) cold
All tires sold in North America must show the maximum load and inflation pressure on the sidewall. Tire pressure is usually measured in pounds per square inch (psi), kilopascals (kPa), or bars. At sea level, one bar equals 100 kilopascals or 14.7 psi.
This marking shows that the tire can carry up to 825 kg (1820 pounds) and that its maximum inflation pressure is 250 kPa (35 psi).
CXHW 7VF1020
This set of letters and numbers shows the manufacturing date, batch, and plant location. Each tire has a unique code, so if there's a problem, tires from the same batch can be identified and fixed before being sold.
Tread wear indicator
Every tire has a Tread Wear Indicator (TWI) triangle on its sidewall. TWI is an indicator of tire wear and a benchmark for checking whether your tire is worn out. Another example of a TWI is a bar that bridges between two tire lugs.
You should replace your tires as soon as the tread wears past the indicators.
Tubeless Steel Belted Radial
A tubeless tire doesn't use a tube. Instead, it holds air with a special rubber inner liner that prevents air from leaking out.
Radial tires have steel belts that run at a 90-degree angle to the tread. This makes the tire strong enough to handle air pressure and the vehicle's weight. Radial tires also flex more, giving better ground contact, traction, and tread life.
Steel-belted bias tires, which are not radial, use two or more layers of nylon cord and two steel belts under the tread. This design makes the tire stronger, provides extra support, and creates a firmer bond with the tread.
Safety Warning
All tires remind users to do regular maintenance and safety checks to keep the right pressure, watch for wear, and spot problems early. The fine print on this Toyo Open Country SxS tire says:
Serious Injury may result from tire failure due to underinflation/overloading. Follow owners manual or tire placard in vehicle. Explosion of the tire/rim assembly due to improper mounting. Only specially trained persons should mount tires. Never exceed 40psi to seat beads. Mount only on 15 inch rim approved for radial tires.
