Considering that many manufacturers recommend using wider profile tires in summer and narrower ones in winter, the instructions may specify several sizes. We do not recommend installing tires with a wide profile, since car manufacturers tested the car in various conditions and selected the optimal tire size that ensures the safest operating mode of the car. Tires of recommended sizes have a certain circumference by the outer diameter, and if you install tires of a different size, this will lead to distortions in the odometer and speedometer readings. Depending on the conditions in which the tires will be used, their seasonality and tread pattern are selected. By seasonality, tires are divided into summer, winter and all-season.
You should not use winter tires in the summer, as they become very soft at elevated temperatures. Such tires wear out quickly in the summer and do not provide safe operation of the car. Summer tires, on the contrary, become very hard in the winter and do not provide good grip on the road.
In summer, when it rains, when driving at high speed, the car may become uncontrollable, as the tire begins to slide (to swim) on the surface of the water. This effect is called aquaplaning. To avoid this, sipes are applied to the tires (grooves) special shape, which allows for efficient drainage of water from the contact patch of the wheel and the road. Very often, such tires are marked accordingly: «Rain» (rain) or «Aqua» (water). It should be noted that if there is no such marking, this does not mean that these tires cannot be used in the rain.
In winter, snowy and icy sections of the road create a problem for drivers. The car becomes difficult to control on such sections, which can lead to an emergency situation. This problem is solved in the following way: winter tires are made with a rougher tread pattern and are often equipped with studs. Such tires are marked accordingly: «M+S» (mud and snow) and/or «Winter» (winter).
Some manufacturers produce all-season tires that are suitable for use in both winter and summer conditions. However, they are generally inferior in performance to specialized tires and are a compromise for regions with mild winters. Such tires are more difficult to manufacture and, therefore, are significantly more expensive than seasonal tires.
Sometimes there is an inscription on the tires «AN season» (all season) or «AN weather» (all-weather). When buying, you need to take into account that these tires may be produced for hot countries, where winter colds remain at around 0°C, so, naturally, such tires are not suitable for our winter.
Make sure that the tires you buy comply with international and Russian standards. Tires that have passed certification are marked with the letter «E» (which indicates compliance with European standards) or an inscription «DOT» (which indicates compliance with American standards), and sometimes both of these markings may be present.
Regardless of international certification, all tires sold in Russia must have a certificate of conformity issued by the Russian State Standard, which conducts its own tests. The seller must present the certificate at the first request of the buyer.