Tyres for passenger cars ensure roadholding ability of the vehicle, are involved in braking and acceleration, create the necessary grip on the road, and absorb vibrations. The choice of tyres determines the vehicle's steerability, driving comfort and safety, the braking distance, fuel consumption and other performance characteristics of the vehicle.
What the marking stands for
- Vehicle class. Tyres for passenger cars are usually marked P.
- Diameter in inches. It may be 14, 16, 21, and so on.
- The rated sectional width. It is the distance between the two points on the opposite sides of the carcass cross-section, most distant from each other. It is measured in millimeters, and may be, for example, 185, 235, or 315.
- Cross-sectional height-to-width percentage ratio. It may be 45, 65, 70, and so on.
- Load and speed ratings. The maximum permissible load per one wheel may be indicated by a number from 60 to 129. Each of these parameters corresponds to a certain value in kilograms. The maximum speed rating is indicated by Latin letters from A to Y, where A is the minimum value (40 km/h) and Y is the maximum (300 km/h).
- Design type. Tyres may be radial - R, or diagonal - D.
- Country of manufacture, brand, and model.
- Tyre types by season:
- M + S (Mud + Snow), M & S, MS, Winter, or a snowflake pictogram - winter tyres;
- A pictogram of the sun or no marking — summer tyres;
- AS (Any Season, All Seasons), R + W (Road + Winter), AW (All Weather, Any Weather) — all-season tyres.
- Tube / tubeless. Tube tyres are marked "TUBE TYPE" (TT), and tubeless ones are marked "TUBELESS" (TL).
- Thermal resistance at high speed. It is usually indicated in the format "Temperature A, B or C", where A is the best value.
- Fuel efficiency rating (descending from A to G).
- Noise level. Most often, it is indicated by a pictogram of sound waves. Their number may be between one and three. One sound wave means that the noise from the tyres is below the regulatory requirements by at least 3 dB; two sound waves mean that the noise matches the requirements, and three sound waves mean that it exceeds the normative requirements.
- Wet grip index. It is marked with letters from A to F, where A means the shortest, and F - the longest braking distance.
- Date of manufacture. Most often it is denoted by four digits: the first two indicate the number of the week, and the last two indicate the year.
- Maximum allowable air pressure. The numeric value and the unit of measure are indicated. The latter usually depends on the country of sales.
How to extend the service life
The average service life of the products is 30-60 thousand km of mileage and depends, in particular, on the storage conditions, the quality of the road surface, the driving style, the total weight of the vehicle, the state of its chassis, axles and suspension, and the intensity of use. Even if a tyre has never been used, do not install it after 5 years from the date of manufacture. The date is indicated by the manufacturer on the tyre.
The degree of tyre wear should be checked by the tread thickness as often as possible: it is usually done once a season with a depth gauge. On summer tyres, this value should be not less than 1.6–2 mm, on winter tyres — not less than 4 mm. Cracks or irregularities on the surface of the tyre also indicate the need for replacement.
In order to prolong the service life of a tyre, monitor the tyre pressure. You can learn its recommended value from the technical documentation, and read it on the tyre itself. In addition, regular inspection of the vehicle is recommended; and wheel balancing should be done after each tyre replacement. For achieving the optimum braking performance and fuel consumption, use the tyres according to the season. It is important to store tyres properly: in a dry room, eliminating the possibility of exposure to aggressive environments (acid, alkali, ozone, fuel).
Autodoc.co.uk is a large online store for tyres for passenger vehicles
In our catalogue of tyres for passenger cars, you will easily find suitable products. All our goods are inexpensive, and we often hold promotions. Place an order at the Autodoc.co.uk online store today, and buy tyres for passenger cars at affordable prices.
Useful information on functions, causes of malfunction, diagnosis and replacement intervals
