There are many parts of a tire that a driver should know if they want to upgrade or replace their tires. Load range and load index are key factors in a tire’s durability and capability, but how are they different? We explain these tire measurements and more below.

What Is a Tire’s Load Range?

The load range of a tire provides valuable information, like the ply construction and the highest pressure the tire can handle when carrying its maximum load. In the old days, tire manufacturers used ply rating, which measured how many cord layers (plies) a tire had, indicating its strength in construction.

But modern tires have to use fewer plies, so the load range replaced this measurement. Drivers can understand a tire’s toughness and air pressure by the load range, represented by a letter on the tire that correlates to the load range chart.

For example, a tire with a C2 load range would have a ply rating of 6 and a maximum load-carrying air pressure of 35 PSI, according to the load range chart.

Remember that some smaller cars may not have load ratings marked on the tires as they’re considered standard with a 4-ply construction and 36 PSI max.

What Is a Tire’s Load Index?

The load index can also be found on the tire’s sidewall and indicates the maximum load a tire can carry. The maximum weight a tire can handle is indicated by a number between 1 to 150, which correlates to a carrying capacity on the load index chart.

Most passenger vehicles have tires with a load index between 70 to 125. So, to figure out the maximum carrying capacity of your vehicle’s tires, find the load index number and the correlating carrying capacity and multiply it by four for the vehicle’s total capacity.

For example, a tire with a load index of 78 would have a carrying capacity of 937 pounds and a total carrying capacity of 3,748 pounds.

What’s the Difference?

As you can see, load index and load range have some similarities and are both important to know, but they have some key differences. While load range is about the construction and air pressure of the tire, it doesn’t tell drivers anything about its carrying capacity.

Drivers who might push their tires to the carrying capacity should know the maximum air pressure from the load range to understand the ideal PSI for the tires.

When replacing or buying new tires, it’s vital to understand the load range and load index of your vehicle’s set. If you need to replace your tires in McAllen, stop by RNR Tire Express or one of our many other locations nationwide. Our tire experts will ensure you get the best tires for your vehicle.

Locations: McAllen, TX