The load index on a tire gives a numerical value for the maximum weight the tire can support when it is inflated to its recommended pressure. Passenger tires have only one load index on the sidewall of the tire where light truck tires have two load index ratings.

The light truck tires have two load index ratings because light truck tires are often used on vehicles with dual rear wheels. The first number gives the load index for the tires when used on single axles. The second number is how much the tire can handle when used on a dual axle.

As an example LT245/75R16 120/116, the tire’s dual load index is 120/116. The load capacity for a single tire application is 3,086 lbs and the load capacity for two tires is 2,756 lbs.

The capacity for two tires is lower than a single tire because

• Even if one tire fails, it ensures that the vehicle can continue to carry the load
• Because of unequal load sharing when the tires are paired together. However, when the tire is acting by itself, it can support a higher weight

The maximum load capacity is only that if the tire is inflated to its maximum air pressure. The maximum inflation pressure listed is not necessarily the recommended inflation pressure. The experts recommend to always use the vehicle placard or owner’s manual to find the specified tire size, load range, and tire inflation pressures.