Understanding tire markings

If you take a look at the sidewall of a tire, you will see a dense sequence of numbers and letters. These markings are much more than just type specifications. They provide precise information about size, construction, load capacity, and permissible speed. For drivers, they are particularly relevant when a tire change is due. Understanding these details ensures that the new tire is technically compatible and offers the required safety and desired performance.

Tire Basics

1. Winter tire symbol

The Alpine symbol (3PMSF) – Maximum safety in winter

The pictogram featuring a snowflake inside a three-peaked mountain (Three-Peak Mountain Snowflake) is the only legally binding seal for genuine winter and all-season tires. It guarantees that the tire has passed strict, standardized tests on snow and ice.

Unlike the outdated "M+S" mark, this symbol gives you the assurance that your tire meets genuine international top-tier standards for winter road conditions. All winter tires in our MASTER family carry this symbol for your maximum protection.

2. Tire width

The first number describes the width of the tire. In this case, it measures 255 millimeters from sidewall to sidewall.

3. Aspect ratio

The following number indicates the ratio of the sidewall height to the tire width. A value of 45 means that the height of the sidewall is 45 percent of the width.

4. Construction type

This is followed by a letter. It indicates the construction of the tire. The R stands for radial construction, which is the standard for road traffic today. In this design, the cord plies in the carcass run at a right angle to the direction of travel. Bias-ply tires are rarer and are marked with a B or D.

5. Rim diameter

The number 19 indicates the diameter of the rim in inches on which the tire is mounted.

6. Load index

This is followed by the load index. The number 104 represents the maximum load the tire can carry at the correct tire pressure. Each index value is strictly defined. Corresponding tables can be found in your vehicle documents or from the tire manufacturer.

Indexwert	Maximallast
92	630 kg
93	650 kg
94	670 kg
95	690 kg
100	800 kg
101	825 kg
102	850 kg
103	875 kg
104	900 kg
105	925 kg

7. Speed index

The speed index concludes the sequence. The letter W indicates a maximum permissible speed of 270 kilometers per hour at full load. Regardless of this, legal speed limits naturally still apply.

Geschwindigkeitsindex	Höchstgeschwindigkeit
L	120 km/h
M	130 km/h
N	140 km/h
Q	160 km/h
R	170 km/h
S	180 km/h
T	190 km/h
U	200 km/h
H	210 km/h
V	240 km/h
Z	240+ km/h
W	270 km/h
Y	300 km/h
(Y)	300+ km/h

8–10 Further markings

Additional information may also appear on the sidewall. This includes details on run-flat properties, original equipment for specific vehicle manufacturers, suitability for mud and snow, and approval according to US regulations. The production week and year are also noted. This information helps to correctly determine the age and intended use of the tire.

8. DOT marking

Confirmation that the tire meets the safety requirements of the U.S. Department of Transportation and is approved for use there.

9. Production week

Indicates the calendar week in which the tire was manufactured.

10. Production year

Shows the year of production and allows for precise determination of the tire's age.

Tire purchase

Buying tires: What really matters when choosing new tires

Buying new tires significantly impacts a vehicle's safety, handling, and efficiency. Tires maintain contact with the road and determine how precisely a car steers, brakes, or accelerates. When buying tires, several factors should be considered: in addition to manufacturer specifications, personal driving style, budget, and regional weather conditions are key decision-making criteria.

Summer

This is why the seasonal tire change is important

Summer tires in winter: Driving on summer tires during winter poses a major safety risk and is not recommended. When temperatures consistently drop into the low single digits, summer tires lose significant grip. Frost, snow, or ice further exacerbate the problem. Changing from summer to winter tires in a timely manner is therefore crucial for driving safety, braking distance, and vehicle control. Summer tires are designed for warm weather and quickly reach their physical limits in winter road conditions.

Winter

Comparing summer and winter tires

Tires and their condition are among a vehicle's most critical safety factors. They directly influence grip, braking distance, and driving stability. Since weather and road conditions change significantly throughout the year, your tires must be suited to them. While winter tires are mandatory in many countries under certain conditions, choosing the right tire is essential for driving safety regardless of legal requirements.