Why is the tread height of a new winter tire interesting? Manufacturers recommend wearing it out not to the minimum allowable value, expressed in exact numbers, but by 50%. When buying a used tire, knowing the initial metric characteristics will help to assess the solidity of its mileage by the residual depth of the pattern.
Automobile tires are assembled from several layers of textile cord and a metal cord breaker - metal wire cord. The sidewalls of the product are covered with a thin layer of rubber, and the running part is covered with a thick one. This massive rubber layer, in fact, is the sole of the tire, and there is a tread.
With convex elements of the pattern, the tread “clings” to the road, moving the car forward, braking, turning. The grooves into which the recesses between the protrusions “merge” drain water and slush from the contact patch.
Spikes and sipes provide grip on slippery surfaces. The first crash into rolled snow, ice. A lot of narrow parallel cuts - lamellas - on the lugs of the tread play the role of a "sucker".
On a note. A tire is a tire that works in tandem with a camera - “covering” it.
The winter tread is characterized by special patterns (with a more contrasting relief, wide grooves) and a special rubber that retains maximum elasticity in cold weather.
Tread pattern of a winter car tire
Groups into which automobile tires are divided depending on the type of tread pattern:
- summer, or road, incompatible with slippery surfaces and deep snow (longitudinally directed pattern, with narrow grooves);
- all-season (they are also universal), but in fact - off-season (the pattern is formed by equal-sized checkers of the same shape);
- winter (complex patterns, from more sparse elements) - on a dry, even road they wear out quickly, make noise, spend excess fuel;
- off-road, or all-terrain (an intricate pattern of separate elements of a complex shape - lugs - and wide cross grooves).
The winter tire pattern may be directional. As a rule, its central zone resembles a Christmas tree. Such a tire is not indifferent in which direction to rotate. You can install it only on one of the sides of the car: on the right or on the left. Hint - arrow on the side of the product.
Such a pattern - arrows (or checkmarks), diverging at the ends from the central axis to the periphery, quickly removes liquid from the zone of contact of the tire with the road (forward and to the sides), “pulls” the car well on a slippery surface, on snow.
Asymmetrical winter tread pattern"assembled" from several longitudinal patterns of different types. (For example, a track of elements resembling arrows - for stability during acceleration and braking on ice).
The tire tread pattern must not differ between wheels of the same axle. Otherwise, the movement of the car along a given trajectory is impossible, and its operation is prohibited by law. (The pattern on a pair of front wheels may differ from the pattern on a pair of rear wheels, but you will need to carry two spares with you - one for each pair).
The pattern of each strip is designed taking into account its place on the tread. Therefore, a tire with an asymmetric tread has an "outer" side and an "inner" side. And since in such a “composite” pattern there is usually at least one track with a directional pattern, such tires are divided into left and right, they are placed only on one of the two sides of the car.
The nature of the pattern divides the tread patterns into "European" and "Scandinavian"
A diagonally directed network of grooves, sipes and lugs along the tread contour (shoulder) are the hallmarks of a pattern that is beneficial when driving in mild winter conditions, on roads cleared of snow, heated from heavy traffic.
A mixture of water, snow, sand, covering the asphalt, is quickly removed from the contact patch of the "European" tread, and the shoulder elements are put into operation when deep snow passes.
The complex pattern of rhombuses and trapeziums is due to the good grip of tires for snowy roads. Even in deep snow, a tire with a "Scandinavian" pattern is able to provide grip on the supporting surface, sufficient for the forward movement of the car without slipping.
On a note. Large elements in the cross-sectioned tread pattern increase the external noise of the car at low speeds: 30 km / h - for cars, 60 - for trucks.
Permissible tread wear
If there is no pattern on the tread, its height is zero. However, the car receives the status of "faulty" much earlier.
What is the height of the tread pattern that indicates that the tire is worn out and needs to be replaced:
- 4 mm - on tires for snowy and icy roads, marked M + S, M & S, M S, with the image of three mountain peaks with a snowflake inside, regardless of the type of vehicle "shod" in it;
- 2 mm - on the tire for the bus (M2, M3);
- 1.6 mm - for a car and truck tire with a maximum permitted weight of up to 3.5 tons (M1, N1, O1, O2);
- 1 mm - for a truck tire with a GVW of more than 3.5 tons (N2, N3, O3, O4);
- 0.8 mm - on the tire of an ATV, moped, motorcycle (L).
These are the requirements of the Basic Provisions for the admission of vehicles for operation (Decree "On the Rules of the Road" No. 1090). The norms for trailer tires are the same as for tractors.
It is possible to reduce tread wear by swapping the rear, front tires, the "spare tire" (if it is not "compact") from time to time - according to the scheme proposed in the car's operating instructions.
Wear indicators
A high rate of abrasion of the tread of a pneumatic tire may indicate a deterioration in the technical condition of the car. Tire "beating" is fraught with wheel imbalance, wear of suspension ball joints, as well as rough, careless driving style. (Turns with a squeal of rubber, the beating of curbs, pits, rails shortens the life of tires).
Is one side of the tread worn more? Probably the wheels are not balanced. The dual tires are not equally worn, their outer diameters differ by 5 mm? The vehicle is considered defective.
Tire wear can be avoided by regular wheel balancing. The driven wheels of most cars are installed perpendicular to the plane of the road, the driving wheels are installed at an angle. If the angle is not correct, the tire will wear prematurely and unevenly.
To help drivers and inspectors - wear indicators:
- protrusions at the bottom of the grooves (in the central zone of the treadmill), the height of each of which is equal to the minimum permitted tread depth;
- a protruding element, the fate of which is to wear out as it wears out and, in the end, disappear, located at the level to which the rubber can be worn;
- figures cut out in different layers of the tread, corresponding to its current depth (one figure is erased - the next one appears).
Pattern height of new winter tires
Manufacturers do not specify the depth of the tread of tires with zero mileage. Perhaps the reason is the difference in this value for different sizes of products. Tread height (mm) of new winter tires of some well-known brands, measured and published by customers:
| Name | Model | Tread Height |
|---|---|---|
| Bridgestone, Blizzak lineup | VRX | 8,1 - 9,2 |
| Revo GZ | 9 | |
| Spike-01 | 10 | |
| DM-V2 | 10 | |
| DM-Z3 | 15 | |
| Bridgestone Ice Cruiser 5000 | Ice Cruiser 5000 | 10,1 |
| Nokian, Hakkapeliitta range | 8 SUVs | 9,5 |
| K 2 SUV | 8,5 | |
| R2 | 8,4 - 8,5 | |
| 8 | 8,9 | |
| 5 | 9,3 | |
| R | 9 | |
| Michelin Latitude X-ice 2 | 8 | |
| Michelin X Ice range | 2Xi2 | 8,2 |
| 3 | 8,6 | |
| North 3, North | 9,4 | |
| Dunlop | Grandtrek At3 | 9 or more |
| Sp Winter Ice02 | 9,7 | |
| Sp Winter Ice02 | 8,8 - 9 | |
| Winter Maxx WM01 | 8,8 - 9 | |
| Yokohama | ice Guard IG30 | 8,4 |
| ice Guard Stud F700Z | 8,9 |
You can roughly determine the depth of the drawing with a coin. But it is better if the driver always has his own meters at hand:
- tread depth (narrow ruler with a movable stop);
- tire pressure - pressure gauge.
Tire pressure and tread wear
If the tire pressure is not correct, the car is out of order. The norm is set by manufacturers: a car (in this case, the rear and front wheels can have different pressure standards) or tires. (Often it is 1.8–2.2 kg/cm).
Every new ride should start with a wheel inspection. Are they in place and all the bolts of their fastening? Are the tires flat? It is better to spend a few minutes and measure the pressure: not by eye, but with a pressure gauge.
Experienced drivers recommend this procedure before every trip.(especially if the car is driven on faulty roads, unpaved, mountainous, crushed stone, gravel, cobblestones, if it is used to work in the city, and, moreover, with increased maneuvering).
Important! Adjusting the air pressure in the chamber means extending the life of the tire. Under-inflated tires, like over-inflated ones, wear out faster.
Figures suitable for comparison with the norm will be shown by a pressure gauge measuring pressure in a cold tire:
- before the start of the trip;
- after the end of the movement - after 2-3 hours.
In extreme cases, you can check the pressure once a week if the car is not working, but only takes the driver to work, to the store and back along a serviceable concrete or asphalt road.
Procedure for measuring pressure:
- remove the cap from the nipple;
- press the rounded end of the measuring device against the valve stem;
- remove the device, take readings from the scale;
- repeat the same steps with the rest of the wheels, including the spare.
If the pressure is too high, the air is bled from the cold tire, in small portions, by pressing the pin in the center of the valve. The chamber with insufficient pressure is pumped up with a compressor at a service station or with its own pump.
A lowered wheel rolls poorly (touch spot, rolling resistance is greater), forces the driver to turn the steering wheel with great effort, and can lead the car to the side. At the same time, the length of the braking distance, the turning radius directly depend on the adhesion of the wheel to the road. (Minimum adhesion coefficient - 0.12).
One of the reasons for the deviation of the car from a given trajectory and uneven tire wear is uneven air pressure in the tires.
The "correct" winter tires for a car, as well as the work designed to prepare the car for autumn-winter operation, are individual for each model and are given in the manufacturer's instructions. It is better for all five wheels to have the same tires and the same internal air pressure. It is important for the driver to remember that prolonged work with increased load is fraught with premature wear of both car parts and tires.
The video explains the tire wear indicators:
Each tire has a tread pattern and is by no means an aesthetic element. The system of notches applied to the tire provides maximum grip of its surface with the road. Thanks to them, water is removed from under the wheels of the car, cleaning from snow and dirt. Therefore, it is so important to monitor the height of the tread pattern.
For a new tire, it will be from 7.5 to 8.5 millimeters. This height is standard for general purpose summer tires, suitable for driving a passenger car on asphalt. So, for an SUV, this number can reach 17 mm.
In some cases, it is possible to purposefully reduce this indicator for a passenger car. We are talking about sports cars that drive almost constantly in high-speed mode. In this case, the tread depth is 5-6 mm.
Minimum depth
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During operation, the tire wears out and gradually wears out. Under the new rules, a vehicle is approved for use if the tread depth of summer tires is at least 1.6 mm. This height is the maximum allowable - then it is already necessary to change the tires to new ones.
Moreover, experts recommend replacing tires already when the residual height reaches 2 mm. This is logical: in this case, it’s not worth the risk, since an almost “bare” tire does not provide proper grip for the car on the road, which can lead to an emergency.
In addition, after this law came into force, traffic police officers can stop and inspect a car, specifically tires. Failure to comply with the proper tread height can result in a fine.
What affects wear?
According to expert estimates, on average, each tire "lives" about 10 years. Given the state of roads in the Russian Federation, as well as the desire of many to drive aggressively, this period can be reduced to 5-6 years. The main factors include:
- travel time on the road;
- appropriate adjustment of toe and camber;
- changing pressure inside the wheel;
- terms of use of the car.
Often, the use of the wrong type of rubber leads to rapid wear. Most of the factors can be avoided if you properly monitor the condition of the car and the tires themselves.
Tire wear assessment
This kind of procedure is carried out for the most part in two cases:
- checking tires for suitability and the need for replacement;
- checking before buying / selling used tires.
And if in the first case everything is clear, in the second one you should be extremely careful: a tire with already 50% wear, although it is subject to operation, will not last as long as we would like. It is difficult to determine this with the naked eye, so you have to measure it.
What are the ways?
There are a number of methods to determine what is the residual depth of the tire:
Additional points
It is important that such measurements must be carried out along the entire tire and in its different sections, since it is often erased unevenly. If this is noted, it is worth, among other things, to check the location of the wheels and adjust their angle.
When checking a tire, you should carefully monitor the presence or absence of mechanical damage: cuts, cracks, chips and non-through holes both on the tread itself and on the sides. Any, even the smallest crack, can cause a car wheel to break while driving, which is extremely unsafe. If it is not possible to eliminate them, the tire must be replaced with a new one.
If a complete replacement of tires for some reason is not feasible, the installation of new tires is carried out on the drive wheels. It is not recommended to change the tire on only one wheel - this will reduce the car's handling. To avoid this, tires are changed on one of the axles.
The safety of driving a car depends on many factors, but one of the main ones is the condition of the tires, the height or depth of the tread. It is tires, taking into account seasonality - summer and winter, that provide excellent grip on the surface of the roadway.
Tires are very different, depending on the transport for which they are selected.
If we talk about passenger cars, then the main types are as follows:
- summer;
- winter (studded or Velcro);
- by destination - off-road (for SUV), sports, regional, highway;
- all-weather.
The depth of the tire pattern depends on the type and purpose of the wheels. We will talk about this in the article.
For an ordinary car new tire tread height is 7.5-8.5mm. Provided that you purchase tires for movement on asphalt roads for general use.
If the motorist owns an SUV or crossover and often goes off-road, the tread depth should be around 17 mm, due to the protruding cups and lugs.
Just in case, we recall that from January 1, 2015, new clauses were introduced into the rules for allowing vehicles to operate, according to which residual tread depth must not be less than 1.6 mm for passenger cars. This applies to both summer and winter tires. Although, it is advisable to install new tires when the tread has worn down to 2 mm. The court has a special badge - TWI, which determines the degree of wear.
You need to understand that there are no specific standards for the height of the tread of new rubber. If you visit a serious store, you should first of all pay attention to the manufacturer: Nokian, Michelin, Goodyear, Bridgestone and many others. These companies are famous for their high quality, therefore, by purchasing their products, you will be completely satisfied.
The tread height will be within 8 mm. Its reduction is allowed in cases where we are talking about tires for high-speed driving in sports mode. The depth then can be about 5-6 millimeters.
Winter tire tread height
For winter tires, tread depth is critical. If in summer you can safely drive on dry asphalt on almost “bald” tires, then in winter your safety depends on the quality of tires, especially when driving at high speeds.
Winter "shoes" for passenger cars can be divided into three types:
- studded;
- Scandinavian type;
- frictional.
The Scandinavian type and spikes are specially made for frosty and snowy winters. The tread depth of new winter tires is 9-10 millimeters. The Scandinavian type of tires is characterized by an asymmetric sparse pattern. Rectangular cups push through snow and ice, which are discharged through small slots - lamellae.
Studs, in principle, do the same job - break up snow and ice, providing traction.
For driving on asphalt, such rubber, of course, is suitable, but it will make a lot of noise. In addition, you risk losing all the spikes when braking hard on bare pavement.
The friction type of winter tires is ideal for driving in warm winters with little snow, in slush and mud. The tread depth here is usually about 9-11 mm. Thanks to thin slots and lugs, the adhesion surface with wet asphalt increases, and all moisture is removed through the lamellas. As a rule, friction rubber has a symmetrical tread pattern.
Good winter tires typically last 4 seasons. That is, the protector is erased much more slowly than in summer.
Tread depth by size
It is also worth noting that the tread height largely depends on the size. So, for summer tires, the depth will be:
- 165/70 R13 - 7-7.5 mm;
- 175/70 R13 - 7-9 mm.
If we talk about universal or winter tires, then the picture is as follows:
- 175/70 R13 - 9-11 mm;
- 187/70 R14 - up to 12 mm;
- 195-205 for 14 - 11-15 mm.
In Russia, in particular, there is a specially approved methodology, which provides the recommended parameters. Domestic manufacturers adhere to them so that the products comply with GOST.
Truck and off-road tires
Truck tires are not divided into summer and winter. They initially come with a powerful deep tread designed for a specific type of coating.
For example, the depth of our popular drawings - rhombuses, goose foot - also depends on the size:
- 240/260-508 (ZIL, GAZ-3307) - 16.3-18.3 mm;
- 280/300/320-508 (LAZ, MAZ, KAMAZ, ZIL) - up to 23 mm.
Well, for special rubber, for example, for mining dump trucks, the requirements are special and the depth can significantly exceed the indicated values.
For crossovers and SUVs with a size of 205-255 and a radius of 15-18 inches, off-road, the tread depth ranges from 12 to 17 millimeters. In principle, there is no special need to measure this parameter - height, when buying at a dealer store, since the quality and condition can be seen with the naked eye.
Every car owner knows that the wheel is one of the most important parts of the car. A vehicle wheel is a disc and a tire. Due to the force of friction, traction with the road surface and the movement of the car occur. The first tires were created in order to reduce the effort required to move loads. Today they are responsible for vehicle handling and safety on the road. The characteristics of tires depend on the chemical composition and tread pattern.
1 Types of drawings - why they are different
Rubber is the main ingredient in a tire. Carbon black, silicic acid, sulfur and other components are added to it to give tires the desired characteristics. The goal of manufacturers is to achieve maximum resistance to external influences, such as friction and elevated temperature.
For different operating conditions, tire manufacturers develop a special tread. Depending on the purpose, tires are divided into:
- road - designed for driving on a hard road surface;
- mud - for extreme conditions (soil, mud);
- universal - used for all types of road surface.
Numerous grooves and longitudinal grooves in the tread of summer tires are designed to drain water. The behavior of the car on the road depends on the type of pattern. The asymmetry and directionality of the tread give better handling, but due to the complexity of production, such tires are more expensive. In addition, they are noisier.
2 Tread depth - what should it be
Over time, the tire wears out and the properties laid down by the manufacturer are lost. And the smaller the tread depth becomes, the stronger the changes for the worse are felt.
There is such a thing as critical tire wear, when it cannot provide normal grip on the road and its use becomes unsafe. The minimum tread height of summer tires is prescribed in the rules of the road. For car tiresit is 1.6 mm, and for buses - 2 mm. With a smaller balance, the operation of the vehicle is prohibited. Let's see why.
When the tread depth becomes smaller, the tire begins to drain water worse. As a result, hydroplaning occurs - partial or even complete loss of traction and, as a result, control. Since the contact surface of the tire with the road surface decreases as wear increases, it is more difficult for the car to brake even on a dry surface. All troubles become even more noticeable at high speeds.
To keep your rides safe, the condition of your tires needs to be checked periodically. The remaining tread depth can be determined in three ways:
- A caliper is the most accurate way to measure. To do this, you need to pull out the depth gauge of the device, lower it to the lowest point and lower the bar until it stops at the top point of the tread. According to the indications on the scale, the remaining rubber is determined.
- Coin and ruler. To perform the measurement, insert a coin into the recess and mark the height of the tread with a marker. Now with the help of a ruler you can find out the condition of the rubber.
- PO indicators. Almost all manufacturers apply various marks that allow you to control the degree of tire wear.
With the first and second control methods, measurements are taken in several places, since wear is uneven.
As for labels, there are several types of them:
- voluminous;
- digital;
- drawings.
Volumetric marks are usually ribs, the height of which will serve as a signal that the tires should be changed.
Digital marks are applied in the form of numbers - from 2 to the value of the tread height of the new tire.
Summer tires sometimes have drop patterns, the disappearance of which signals the danger of aquaplaning.
3 Causes of premature wear
The tire wear rate is affected not only by its chemical composition, but also by some other factors. Tire wear can be caused by:
- The pressure is above or below the set value. Under normal tire pressure, the tread surface is fully in contact with the road surface. When the pressure is lower than needed, the rubber wears out at the edges. If the wheels are pumped - erasing occurs in the middle of the tread.
- Incorrect wheel alignment. In this case, the rubber is "eaten" along the outer or inner edge of the wheel, depending on which way it is tilted.
In both cases, the load is not distributed evenly, but on certain sections of the wheel. Because of this, the rubber wears down to zero in one place, while wear remains acceptable in another.
4 Shelf life of wheels
In addition to the allowable wear of tires, the natural aging of rubber should be taken into account. Over time, it loses elasticity, becomes hard. Sometimes cracks appear on the surface of the tire, due to which air can leak in the future. There are even cases when the tire explodes.
No manufacturer gives information about how many years a tire can be used. But each tire has a label indicating the year and week of manufacture. You need to remember this point when buying new tires. It's not worth the risk, it's better to opt for fresh tires.
When buying used wheels, you should pay attention to the following points:
- degree of wear;
- wear uniformity;
- year of issue;
- visual condition (cracks, delaminations).
In addition to the described methods for determining the need to replace old tires with new ones, you should also rely on your own feelings. If the car has become worse to slow down, the grip is insufficient, or control is lost on a wet road, then you should not hesitate to replace tires.
The tread depth of winter tires varies depending on the type of tire category. The tread pattern can remove water, slush and snow at the traction point. It is extremely important to pick up wheels under your climatic conditions. There are no universal solutions and you need to approach the choice carefully. The tread depth of winter tires depends on the category:
- European.
- Scandinavian.
- directed;
- non-directional;
- asymmetric.
Permissible tread depth for winter tires
According to the technical regulations of the Customs Union of 2016, the remaining tread depth of the tires must be 4 mm. This should reduce the number of accidents by 43%. The fine will be increased from 500 to 2000 rubles. It seems that traffic police officers will now have a ruler with a depth gauge in their arsenal.
European
The main application is the grip of the tread on wet asphalt and wet snow. Therefore, they are indented by drainage channels and have a slightly directed wedge pattern. Thus, removing it for better drainage of the contact patch of the tread and asphalt. They perform well on ice at low temperatures from -15˚С. Ideal for the city, where roads are sprinkled with reagents, providing slush removal. The tread depth of new winter tires is 5-6 mm.
Scandinavian
Serves for biting into the frozen surface, providing better grip. This is ensured by a large number of rectangles and rhombuses placed at a great distance. The presence of small strips (lamellae) is very important. Thus, the machine pushes through a solid surface of ice or crust. But this type of tire provides poor braking on wet pavement. The tread depth of new winter tires is 9-10 mm.
Now we know that the tread depth of winter tires is different and is:
- 5-6 millimeters for Europeans;
- 9-10 millimeters for the Scandinavian.
There is one caveat, if the European type loses 1 millimeter and it is already on the verge of a foul, but fulfills its functions, then for the Scandinavian type a loss of 5 millimeters will make driving impossible in principle. Although according to the rules, everything is within the normal range. As a result, the regulations are not entirely accurate. It would have been better to introduce an acceptable percentage of tire wear from the factory value, say 30%. In this case, the minimum bar for European would be 4 millimeters, and for Scandinavian 7 millimeters.
Tire tread pattern
Separately, it is worth mentioning off-road tires. They have a high winter tire tread and a V-shaped pattern. But these tires are completely unsuitable for driving on the roads. Rubber is quickly erased, and this type of tread negatively affects the grip parameters.
Directed
Ideal for winter driving on asphalt, providing good directional and lateral stability. Well removing water from the contact patch. The picture indicates the direction of rotation of the wheel and cannot be rearranged. This is one of the downsides. In case of a puncture, it may turn out that you have a spare tire for the wrong wheel and in difficult weather conditions this will affect handling.
Omnidirectional
This type of tire is universal and is installed on most cars at the production stage. They do not have a direction of rotation and can be installed on either side. As a rule, a car with this type of pattern has good stability on the road. Operation and replacement with a new set is not expensive. they don't have a high price range.
Asymmetrical
Such tires are something in between the previous options. The outer part provides traction on asphalt, while the inner part should provide off-road function. Under specific conditions, they will lose to profile rubber, since the usable area is reduced by 2 times, but a certain semblance of versatility is created. Well suited for the conditions of a country warm winter.
How to measure tread depth
In order to find out what the tread depth of winter tires is, a depth gauge or a regular caliper is used. It is better to take measurements in at least 6 places. Tires wear differently depending on how the vehicle is used.
Also, some manufacturers make wear indicators in the form of levels, numbers, and some models change color. There are no recommendations about how many seasons it is worth replacing tires, it all depends on your driving style and the quality of the tires.
