Ply Rating & Load Range Guide

What is Ply Rating?

Historically, "ply rating" referred to the actual number of cotton layers (plies) used in a tire's construction, which indicated its strength. Modern tires use stronger materials like steel and nylon, so the ply rating is now an equivalency rating. For example, a tire with a "10-Ply Rating" might not have 10 physical plies but has the strength equivalent to an older 10-ply cotton tire.

Higher ply ratings generally mean a stronger, more durable tire capable of carrying heavier loads and withstanding more abuse.

What is Load Range?

Load Range is a letter-based system (e.g., B, C, D, E, F) that has largely replaced ply ratings for indicating a tire's load-carrying capacity, particularly for Light Truck (LT) and Special Trailer (ST) tires. Each load range letter corresponds to a specific ply rating equivalent and a maximum inflation pressure required to achieve that load capacity.

Why Do These Ratings Matter?

• Load Capacity: The primary reason. You must choose tires with a load range/ply rating that meets or exceeds your vehicle manufacturer's recommendations and the actual load you'll be carrying. This is especially important for trucks and trailers.
• Durability: Higher ply ratings/load ranges often mean a tougher tire, more resistant to punctures and damage, especially in demanding off-road or construction environments.
• Inflation Pressure: Tires with higher load ranges require higher inflation pressures to achieve their maximum load capacity. Always inflate to the pressure recommended on your vehicle's placard or tire sidewall for the specific load.