Tire load index - what does it mean and how to choose it correctly? All the most important information

When buying new tires for your car, you must remember to choose the right one. Most people are guided by size, obviously, but we must not forget about another key variable - tire load index. load index). This marking can be found on each tire and in the product description (if you order tires, for example, via the Internet). This is because it is of key importance in the context of buying the right product for a given vehicle. Why is the index so important? More on this later in the text.

What is Tire Load Index?

The tire load index determines the maximum load at which the tire can operate while maintaining its properties. It indicates exactly how many kilograms one tire can “carry” when driving at the maximum permitted speed.

The index information is located on the sidewall of each tire immediately after the size designation. This value consists of two or three digits (immediately followed by a letter, i.e. the speed index). However, it is worth knowing that it does not contain specific information, but is only a link to the corresponding table, in which you can check what exactly this value means. You can read about the most popular tire load indices below.

Choose the tire load index that suits your vehicle

You don't have to figure out which tire load index is right for your vehicle. This is because the manufacturer is obliged to provide detailed information on this matter. You'll find them on the nameplate, which is usually found on the driver's door pillar (or on the fuel cap), as well as in the owner's manual that comes with every new car you buy. This applies to both winter and summer tyres, as well as all season tyres.

Knowing the index, you can also find out the maximum permissible weight of your vehicle. All you need to do is multiply the value found in the indicated location by the number of tires that are installed on your car. 

Wrongly chosen index - what are the consequences?

When choosing tires, you can, of course, make a mistake and buy tires with a different load index than the manufacturer suggests. In this situation, of course, there are two options:

• A higher tire load index is not such a big problem in this case, because usually tires with a higher index are generally better. This will have a positive effect on the driving characteristics of the car, such as steering precision or level of stability. However, everything has its drawbacks - a higher index means more consumption, and at the same time, faster wear of suspension and brake parts. Higher rolling speeds will also result in higher fuel consumption;
• A lower tire load index - in this case, we can talk about a critical error. Understating the ratio in relation to the mass of the vehicle can lead to many negative consequences, including the very likely failure of the tire during high-speed driving. Using tires with a lower load index than specified by the manufacturer may result in a fine, as well as withholding compensation from the insurer and/or voiding the vehicle's manufacturer's warranty.

What tires for passenger cars are the most frequently chosen index

As already mentioned, the tire load index must be selected in accordance with the information provided by the manufacturer. However, it so happened that most passenger cars fit into the value of "91", which means a load capacity of 615 kg. These are tires that work well for slightly larger city vehicles or most station wagons and SUVs. However, this is only an advisory statement and should not automatically be considered suitable for your vehicle. You will find the corresponding value on the rating plate.

The tire load index starts at 60 and ends at 170. The former refers to the smallest vehicles authorized for urban traffic, while the latter refers to the largest (for example, agricultural or construction machinery). For passenger cars, the specified fragment of the table should cover most of them:

• 88 – 560 kg;
• 89 – 580 kg;
• 90 – 600 kg;
• 91 – 615 kg;
• 92 – 630 kg;
• 93 – 650 kg;
• 94 – 670 kg;
• 95 – 690 kg;
• 96 – 710 kg;
• 97 – 730 kg;
• 98 – 750 kg;
• 99 - 775 kg.

Dual Tire Load Index - Trucks and Vans

In the case of larger vehicles, a so-called double tire load index may appear. The correct reading depends on how many wheels a particular car model has. If the rear axle consists of four, then you only read the second value printed on the tire - in your case this is the decisive value. The best way to make sure you read the value correctly is to multiply the index by the number of wheels and compare it to the car's maximum weight. If they match, then you read the value correctly.

The tire load index is an important value, as it directly affects the safety and driving comfort. The use of the car must be carried out in accordance with the recommendations of the manufacturer - this also applies to the purchase of substitutes, such as tires. Checking all parameters is critical in this case. Remember to make sure when buying a car (especially a used one) which tires will be the best, and what kind of wheels are on the car. The gross weight of the vehicle is also a value that should interest you. Not only in the context of tire selection.