Classification (marking) tires

Labelling of tires is a label disposed on the tire sidewall. Being able to correctly decipher this “legend”, the motorist will be able to learn a lot of useful information about the size of the tire load capacity, speed and its operating characteristics.

Note that the text labeling is applied only on the tire rim, and the inscription is duplicated on both sides. In this article we look at how to decipher the markings of a car tire.

code color

Markings are not only text, but also the color. The last is applied to the tread or sidewall of a new tire. Such labeling is not durable, and after some time (after washing or many kilometers run) they wear.

In most cases, color markings contain the information for the manufacturer, but can sometimes be helpful and experienced tire repairers. Particularly, color marks are used to mark locations along the perimeter with the largest tire imbalance.

So, for the Bridgestone tire company uses the following color markings:
– The yellow dot. It indicates the most easy place.
– Red dot. It indicates heterogeneity of the material in the tire, which, in most cases, a simple superposition of layers (adhesions place).
– White stamp. It indicates that the tire has been tested OTC.

Also, the majority of tires can be detected continuous strip that runs around the perimeter of the tire. It can be any color perfectly and does not carry any useful information. Its purpose only technical – it points to the workpiece, which has been cut from the material to the tires. Therefore, if one tire, this band is yellow, and the other – blue, it only shows that the tire data from different parties.

Text marking

The most informative label is the inscription on the sidewall of the tire, consisting of a set of numbers and letters. Let’s learn to “read” such marking and for clarity analyze the following inscription – 195/65 R15 91T, where:

195 – indicates the section width of the tire in millimeters;
65 – is a percentage of the tire section height to its width. This number determines the height of the tire at its specified width. The labeling of some tires, this figure may be missing. In this case the value is 80%, and such tires are called “full-profile”;
The R – this letter is used to denote the tire carcass structure, although some motorists mistakenly believe that it is the radius. In this case, it is radial – R. Earlier also produced tires with a diagonal design, but now they have not found;

15 – indicates the diameter of the disc in inches, that is, the inner diameter of the tire.

These numbers and letters are used to denote the tire size. Focusing on them, the motorist will be able to easily pick up the appropriate tire for specific drives and for a specific car. These are very important settings for a particular disc fits only a specific tire dimensions.

Numbers and letters coming after standard size tires indicate its power and speed characteristics.

91 – load index is the tire capacity. It specifies the maximum possible load, which can operate the bus, without being destroyed and completely corresponding to specified by the manufacturer specifications. Learn the exact values possible for the plate located at the end of the article.

The T – is the speed of the index, which is used to determine the maximum speed at which the tire can be used. There is nothing wrong if the motorist exceeds the allowed value for a short period of time and, for example, instead of permissible 190 km / h will go to 210 km / h. However, if the driver will repeatedly exceed the speed limit, the tire can deform and collapse as a result of overheating.

Decoding speed index tires

speed index

















km / h
















> 240

Tyre Manufacturers determine the maximum allowable speed during bench tests, and they recommend to motorists driving at a speed of 10-15% below to maximize tire life.

Furthermore, some tires may be written Max Load (maximum load) and then the limit values ​​indicated in kilograms or pounds.

Also for light trucks and vans produce special multi-layer bus, capable of operating at high loads. They mark the inscription REINFORCED or simply the letter “C”, which is indicated when the machine diameter (for example, 195/70 R15 C).

Marking tires production date

tire manufacturing date as indicated on the tire sidewall. To refer to it using a four-digit number, which is indicated in an oval immediately after the DOT standard code. The first two numbers indicate the week of the year, and the rest – the year of manufacture.

The old tires, produced in the 80s, only three digits are used for marking the date. Then (in the 90s), these numbers began to add triangle, and in recent years, manufacturing plants are used for marking the date format only four.

Labelling of tires by American standards

Tyre marking American manufacturers is different from the European, and there are just two options refer to standard sizes. The first one is quite similar to the European label, but before the size designation is placed or the letter “P” (Passenger – car tire) or code “LT” (Light Truck – tires for light trucks and vans). In this case, size marking looks like this P 195/70 R14 or so LT 235/75 R15.

And here is another mark of American tires is significantly different from the European one. In this case, the sizes of the tires will be listed like this: 31 × 10.5 R15, where the numbers “31” and “10.5” indicate an outer diameter and width of a tire in inches, respectively, well, R15 “read” as well as from European tires.

Additional designations on tires

Some manufacturers use in marking additional notations tires. Below we look at the most common ones:

The S & the M (the Mud + Snow). These all-season tires are considered and suitable even for driving on snow or mud.

Season the All – weather tire, which can be operated all year round. Note that the seasonal tire symbolic patterns can be applied as well.

The Rotation – tires with this marking are directional, and on the sidewall of the tire is further applied to the arrow indicating the direction of rotation of the tire.

Outside and the Inside – tires with this marking are asymmetrical, and when installed you must follow exactly the installation rules for tires on the drive. For example, when installing a side of the tire with the inscription Outside (outside) must be on the outside of the machine, and the side with Inside inscription (inner side) – from the inside.

Left or the Right – indicate whether it is right or left tire. When mounting the tire must be such that the right tire was on the right and left – left.

Tubeless – such an inscription indicates that this is a tubeless tire.

Type Tube – indicates that the tire must be operated only with a camera.

Pressure the MAX – the maximum allowable pressure in the tire, indicated in kPa.

Rain, Water Water, the Aqua (or symbolic figures in the form of an umbrella or drops) – indicate that the tire is specifically designed for wet weather.

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by Cars NB