Tyre load rating and tyre speed rating

What do these tyre ratings mean? Do you have to comply with them when you replace your tyres? We will discuss this in this article.

What is the tyre load rating?

The tyre load rating is a numerical code which corresponds to a maximum load (in kg) that can be carried by a single tyre.  The load rating and corresponding maximum tyre loads are listed in a standard table.

To identify the maximum load your tyre can carry, or the load index recommended by your vehicle manufacturer, simply do the following:

On the sidewall of your tyre, you will find a string of numbers and letters that look like this:

You may also find them on the sticker on your driver's door or your vehicle owner’s  manual.

These numbers and letters vary between tyres. They indicate the tyre dimensions, load and speed ratings.

Let's see what this coding means:

Note that tyres of the same dimension can have different tyre load and speed ratings. This is why it is important to understand the dimension, tyre speed and tyre load rating before replacing tyres.

In this example, the tyre load rating is 91.

Once you have noted the tyre load rating, you can find the maximum single tyre load that it refers to by consulting this table:

In our example, we see that the tyre load rating of 91 corresponds to a maximum tyre load of 615 kg with the right pressure.

Some tyres are also marked XL. This stands for "Extra Load".

It simply means that the tyre has been reinforced to be able to carry heavier loads than standard tyres of the same dimension. Let’s use the same tyre size : 205/55R16 94V XL. In this case the load capacity of this tyre with the same dimension as in our previous example is now 650 kg instead of 615 kg.

As mentioned above, the tyre load rating corresponds to a maximum load (in kg) that can be carried by a single tyre.

However “who can do more can do less” and it is of course possible to fit your car with tyres that have a higher load rating than the manufacturer’s specification. However, you will not necessarily be able to carry more load than the original manufacturer’s specification because there is a limit on the maximum permissible axle load for your vehicle, independent of the tyre load capacity.

What about the size? Is it possible to change it?
You can find the answer to this question in our article on changing the size of a tyre.

What is the tyre speed rating?

The tyre speed rating indicates the maximum speed at which a tyre can carry its maximum load.

On the sidewall of your tyre (or the sticker in the driver's door, or the owner’s manual), the speed rating is defined by a letter right next to the load rating

Here, the tyre speed rating is V.

To find out what speed this index corresponds to, simply refer to the tyre speed rating chart:

For example, if the tyre has a speed rating of V, then the maximum speed it can sustain is 149 mph (240 km/h).

When your tyres are worn out, it is perfectly possible to replace them with tyres with a higher speed index than the one indicated on the old ones. However, you should never mount tyres with a lower speed index unless fitting tyres with winter capacities such as winter tyres or All Season Tires, as discussed below.

There are specific cases for W, Y and (Y) speed ratings, which are specific to high-speed vehicles (> 270km/h). If you are concerned, please ask your dealer for advice.

As we said earlier, "who can do more can do less". With this in mind, we've simplified our Sport ranges, such as the MICHELIN Pilot Sport4, MICHELIN Pilot Sport4S and MICHELIN Pilot Sport 5, to make it easier for consumers to find their way around.

Most of the sizes in these ranges now have HIGHER possible load ratings than the original ones in order to meet all requirements

Most of the sizes in these ranges now have HIGHER possible load ratings, but as these are higher than or equal to the original ones, they meet all requirements.

Here's a concrete example:

If your original tyre size is 225/45 R17 91 V, you can opt for size 225/45 R17 94 Y.

The 94 load index means that the tyre is capable of carrying a higher load (up to 670 kg) than your original tyre (up to 615 kg). A tyre of the same size with a higher load index is therefore perfectly compatible.

The speed rating is also compatible if it is higher.

If you use tyres with winter capacities (marked 3PMSF : either winter tyres or All Season Tyres), the speed rating may be lower than that of your summer tyres or the original tyre fitted to your vehicle.

Why is this possible? Tyres with winter capacities are designed differently for driving in difficult climatic conditions (snowy, icy roads, etc.) and may not have the same speed rating. 

However, generally you drive at a lower speed in winter than you would on dry roads with summer tyres. In the UK the speed rating of tyres with winter capacities will still be in excess of the national speed limit. In any case, the driver must limit the speed of the car so not to exceed the maximum speed of the tyre.

What about the size? Is it possible to change it?

You can find the answer to this question in our article on changing the size of a tyre.