Important tread pattern

Is it possible to use tires with different tread patterns on compound axles of a car? I heard that there are new laws about this.

Deputy Inspector Mariusz Olko from the Traffic Department of the Provincial Police Headquarters in Wrocław answers readers' questions.

-

- Yes it's true. From mid-March, a new order of the Minister of Infrastructure on the technical condition of vehicles and the amount of their necessary equipment (Journal of Laws of 2003, No. 32, art. 262) came into force, which slightly changed the previous Rules for the use of tires in a car. In the most important of them, it became possible to use tires with different tread patterns on compound axles.

What are component axes?

By definition, a composite axle is a set of two or more axles in which the distance between adjacent axles is not less than 1 meter and not more than 2 meters. This does not apply to mopeds, motorcycles, cars and agricultural tractors.

What's on wheels?

The vehicle must be equipped with pneumatic tires, the load capacity of which corresponds to the pressure in the wheels and the maximum speed of the vehicle; tire pressure should be in accordance with the manufacturer's recommendations for the tire and vehicle load.

The legislator allows the installation on a vehicle of a spare wheel with parameters different from the parameters of a commonly used support wheel, provided that such a wheel is included in the standard equipment of the vehicle - under the conditions established by the vehicle manufacturer. However, they can be used in exceptional cases (short-term).

The law prohibits

The vehicle must not be equipped with tires:

different design, including tread pattern, on wheels of the same axle, with the exception of compound axles;

in the case of a two-axle vehicle with single wheels:

– diagonal or diagonal with a belt on the wheels of the rear axle, if radial tires are installed on the wheels of the front axle,

- diagonal on the wheels of the rear axle in the presence of diagonal tires with lapping on the wheels of the front axle;

different structure on the axes of the components;

indicators of which show the limits of tread wear, and for tires not equipped with such indicators, with a tread depth of less than 1,6 mm; for buses capable of speeds up to 100 km/h, the tread depth must be at least 3 mm.

with visible cracks that expose or break their matrix;

with permanently installed anti-slip elements protruding outwards.