The question of where to look up the year of manufacture of a tire does not seem so stupid if you remember that the properties of rubber change over time. And this fact does not depend on whether it was used before or was simply lying in the supplier’s warehouse.
Experts recommend that every car enthusiast check information about the production time of wheels before purchasing them. And if you don’t know how to do this, here are effective options.
How to find out the production date of tires
To begin with, we note that all manufacturers of tires, be it branded Pirelli or inexpensive Kama, put information about the date of their production on the sidewall, along with numerous other markings.
A distinctive feature of the information that sets it apart from others is the oval stamp, and this fact does not depend on the country of manufacture or any other features.
But the decoding itself is not as banal as we are used to. It does not lead to a specific date, but only talks about the year and week in a row. For example, if the oval stamp shows the numbers 1619, then the tire was produced in the 16th week of 2022, which is April.
The specific number, much less production time, is not indicated by any of the manufacturers. For rubber produced before 2000, the marking code consists of three digits, where the first two are the week, and the third is the last digit of the year.
Decoding
Additionally, a wide range of different information can be indicated on the sidewall of the wheel. For example, this includes the following:
- XL or Extra Load;
- AS or All Season;
- pictogram in the form of a snowflake;
- umbrella - rain tires;
- Inside;
- RSC;
- Rotation;
- Max Pressure;
- Reinforced;
- letter E;
- Temperature;
- Traction;
- Treadwear;
- Y.W.I.;
- DOT.
It should be noted that these designations indicate a variety of additional functions. For example, if a car is used for commercial transportation, then XL tires are indispensable. This allows you to operate the machine under increased load. For example, when specifying the 91T index with this mark, you can easily load 670 kg instead of the usual 615 kg. Moreover, there is a special index table.
It is relatively rare, but still possible, to find products on sale labeled as AS. Moreover, these indicate the possibility of use in any weather. The designation All Season is also often used. The presence of a special pictogram in the form of a snowflake suggests the possibility of operation in winter conditions. In the absence of a “snowflake”, rubber can only be used in the summer.
Rain tires are a separate category. They are usually used in regions where rain is a frequent occurrence. Such models have increased resistance to aquaplaning. They are indicated by a corresponding inscription or a special pictogram in the form of an “umbrella”. There is also the inscription Aqua.
Inside or Outside are asymmetrical tires. This implies the need to respect the direction of rotation. Typically, the Outside inscription should be on the inside, located closer to the engine. Rotation – also indicates the direction of rotation of the wheel. Represents a special arrow. Tubeless – are tires that do not require a tube.
Max Pressure – maximum allowable pressure in the wheel. Also, on almost all tire models without exception, the maximum pressure on the wheel with an external load is prescribed. This means dividing the total weight of the vehicle and passengers by 4. This value must be compared with that indicated on the sidewall of the tire. The maximum pressure is indicated by the designation Max Load.
Reinforced or a combination of the letters RF - the manufacturer thus indicates the use of several layers in the tread. This makes the tire more resistant to long-term explantation. Such models can easily withstand increased loads.
Is labeling required?
We found out where to look at the year of manufacture of rubber, but is it always there or is marking not a legal requirement for manufacturers?
In Russia, the Department of Transport is responsible for the certification of car tires, and it has decided that all wheels sold in our country must be marked.
Otherwise, the product will not be able to appear on the market. The strict rule is followed by all leading suppliers, including our most popular drivers Michelin, Nokian and Yokohama.
As for the European Union, America and other countries, other services are responsible for special information marks, but information about the production period, technical features of the wheel, its size and much more is required there too. Therefore, you can find the treasured numbers in any case.
It is important to note: Externally, the marking of American tires differs from Russian and European ones, so you need to read it according to different rules.
American labeling system
The above is the European notation system. American markings are applied in accordance with the quality standards of the US Department of Transportation. Such tires are produced for use in the North American states. All designations are expressed in inches.
Marking 31 X 10.5 R 15
31 — Tire outer diameter
10.5 — Section size
R — Radial arrangement of cord threads
15 — Bore diameter
Tires manufactured before 2000
We've already touched lightly on the topic of coding differences between tires manufactured before the early 2000s, but let's look at this topic in a little more detail. The encoding in the 20th century was three-digit, so it might look something like this: “248” or “*248*”. In this case, the first two digits will always indicate the week of release, and the third - the year.
But what specific year are we talking about: 98 or 88? Wheels produced in 1998 are marked with asterisks. Sometimes they are replaced with a triangle or a space. Tires created in 1988 are identified only by numbers, without spaces or special characters.
And this applies to the entire time period before 1990. It is unlikely that you will be able to find rubber made in the 70s, but in terms of markings it is no different from a product made in the 80s.
This shortcoming is due to the fact that previously the wheels were used for much less than ten years; there was simply no need for additional designation.
Symbols related to tread pattern
According to the nature of the pattern, protectors are divided into:
- Non-directional. Symmetrical, relative to its longitudinal axis, or universal
- Directed. Symmetrical. They have recesses for better water drainage
- Asymmetrical. Combines several useful properties. The outer side can provide better grip on dry surfaces, and the inner side can work to drain water
When installing wheels, the following designations are taken into account:
Outside - The outer side of an asymmetric tire
Inside - The inner side of the asymmetrical wheel
Rotation - This inscription in conjunction with an arrow indicates the direction of movement of the wheel. This indicates that the tread is directional. If installed incorrectly, water accumulates in the tread grooves, which creates conditions for hydroplaning.
Do tires have an expiration date?
We figured out how to determine the year of manufacture of a tire, depending on its generation, but is it really that important? Externally, wheels from the 80s are not much different from modern ones, especially if all this time they were in storage and not in use.
Any manufacturer, be it American Goodyear or Japanese Bridgestone, gives a guarantee of only 5 years for its products. This means that during this period the rubber will not change its elasticity, strength, or other technical characteristics. It doesn't matter whether the wheels were actually used or not.
But modern technologies create high-quality tires that, if properly stored, can remain normal for a longer period of time - 10 years. After this period, it is still not worth buying tires, even if they continued to be in the warehouse and were not used.
Summary
As it becomes clear, there are quite a few ways to find out the age of Michelin car tires. The most important thing is to try to determine the age as approximately as possible, since the exact age is very, very difficult to determine, especially if the car tires have already been used by some driver before.
The most important thing to pay attention to when determining age is determining the tread height of Michelin tires. To do this, it is enough to measure this value as accurately as possible and compare it with the standard value. If the difference between these values is relatively small, then the age of such tires will also be small. As this value increases, the age of car tires will correspondingly increase.
The most important thing for drivers is to try to maintain the quality of the Michelin tires they use for as long as possible. To do this, it is enough to treat rubber products as carefully and carefully as possible.
Manufacturer's Warranties and Mileage Standards
We found out where the year of manufacture is indicated on the tires and whether it is worth buying stale tires. It's time to talk in more detail about the manufacturer's warranty regarding wear and tear. After all, many car enthusiasts buy tires that have already been used.
Performance standards are set by the certifying body and depend on the type of vehicle the wheels are installed on. According to them, on cars, trucks and minibuses whose weight does not exceed two tons, the maximum mileage is 45 thousand kilometers.
If a heavy vehicle weighs from two to four tons, its critical mileage is set at 60 thousand kilometers, and for road trains with a large weight - up to 70 thousand. After this, the tires must be disposed of, because their further use is not safe.
Important information
Tires are available in tubed and tubeless versions. Tubeless ones are mounted on reinforced rims with more reliable fastening elements.
Bridgestone tires are classified according to their purpose:
- Road or summer. Designed for use at temperatures above +5 o C. Provide good adhesion to dry and wet surfaces. They perform worst on dirt roads. Not suitable for icy or snowy areas.
- Winter. In terms of dynamic properties they are inferior to summer ones. Adapted for movement on slippery, snowy areas. There is a possibility of additional studding of the tread.
- All-season. They can be used in summer and winter, but their grip characteristics are inferior to seasonal tires.
- Universal. Installed on SUVs. They hold traction well and provide cross-country ability on both dirt roads and asphalt surfaces.
- Special tires with improved cross-country ability. Allows you to move on soft ground and in off-road conditions. Installed on special equipment.
Special markings are used to indicate seasonality.
Why do you need to know the year of manufacture of tires?
Is it so important to know where to look for the year of manufacture on tires, given that the range in modern tire centers is updated every season? In fact, the idea that stores constantly change their assortment is erroneous.
Yes, new models just released on the market will most likely appear in them. But previous generations are simply put away in storage until the next season, rather than being disposed of or returned to the supplier.
What does it mean? To put it as simply as possible, popular models from Cordiant, Continental, Hankook or other manufacturers, ordered by a tire center in large quantities, will simply wait out the season in the store’s warehouse and then be put up for sale again.
No one can say for sure how long this cycle will last. Therefore, the risk of running into a product released 3-4 years ago is high. Yes, you will have a few more years left, but much less than you would like.
Sellers' tricks
Often when selling, we can see tires neatly stacked on racks. However, before that, they traveled for a long, long time in a railway carriage, stacked in piles. Sellers, of course, won't tell you about this.
Next, imagine the situation that the summer season has ended, but there are still summer tires in the warehouse. What to do? After all, we need to make room for winter tires! Summer tires will simply be removed from the racks and thrown, at best, into the snow under a canopy. The same thing will happen with winter ones at the end of the season. This batch will then be sold at reduced prices at the beginning of the season as a new collection or new arrival.
In Europe, tires are stored for no more than five years. After this, they will be sent to Russia or other countries where, by law, the storage period is not so strictly regulated. This will usually also happen early in the season.
Refrain from buying winter tires before the start of winter or summer tires in early spring - it is quite possible that they will try to sell you an expired tire.
Tips for drivers
How to find out and decipher the year of manufacture of a tire is not the only question that worries car enthusiasts. There are a lot of other problems that can be avoided when buying new tires if you follow the recommendations:
- Take care to properly store tires during the off-season so that you change them less often. Buy special bags, but use them no longer than one season. Get new ones for next time.
- Place wheels in a sheltered location away from sunlight. It literally dries out the rubber, shortening its life.
- Monitor tire pressure, for example using sensors. This will increase safety and reduce wear at the same time.
- Monitor tread wear levels. It should be uniform. If this is not the case, then the car has wheel alignment problems.
- Buy tires from trusted manufacturers. They care about their status in the car enthusiast community and always monitor the quality of their products.
It is important to note: Sometimes Russian tire centers, trying to earn more, buy tires in bulk from European countries that have been in storage for at least three years. There it is no longer possible to put such products up for sale, and our drivers are not yet accustomed to tracking the production date. Be careful when purchasing.
Question answer
The speed index is the maximum permissible speed at which a properly inflated tire can be driven under load. The speed index, indicated by a letter, is located after the load index on the sidewall of the tire. For example, for a tire with speed index V, the maximum speed is 240 km/h. The tire load index is a numerical expression of the maximum load that the tire can withstand at the speed indicated by the corresponding index and at a certain air pressure in it. For example, for a tire with a load index of 116, the maximum load is 1250 kg.
The country of manufacture is indicated on the sidewall of each tire. For example, the inscription Made in Japan indicates that the tire was made in Japan.
You can find the production date in the DOT number, which is located on the sidewall of each tire. Three "DOT" letters on the sidewall indicate that the tire meets safety standards set by the U.S. Department of Transportation and is approved for highway use.
Example: DOT YDLX P8U 4617
After the inscription “DOT” there is an alphanumeric code of 11 characters. The first two characters after "DOT" indicate the tire manufacturer and manufacturer code. The next 5 characters are a code defined by each manufacturer and denoting internal codification. The eighth and ninth digits correspond to the week the tire was manufactured. The last number (or numbers) indicates the year the tire was manufactured. The marking in the example means that the tire was manufactured in the 46th week of 2022.
The mileage on a set of tires greatly depends on a number of factors, such as operating conditions, and the quality of the road surface. The way you drive your car has a huge impact on the life of your tires and their wear. Regular heavy acceleration and braking will significantly reduce tire life.
The appearance of uneven wear can be caused by various reasons, such as incorrect tire pressure, malfunctions of the vehicle suspension, incorrect wheel alignment, and violations of operating conditions. To prevent uneven wear, we recommend regularly inspecting your tires and remembering to monitor tire pressure and the technical condition of your vehicle. When changing tires seasonally, we recommend swapping wheels.
The maximum permissible level of wear is determined by the Road Traffic Rules of the Russian Federation and is equal to 1.6 mm of rubber over the entire tread surface for summer car tires. For winter tires, the legal wear limit is 4 mm.
Tread patterns are classified into three main types: non-directional asymmetrical, directional symmetrical and symmetrical.
Directed:
Tires with a directional tread pattern are ideal for sports cars that regularly drive on wet roads. They are also recommended for driving on snowy roads. Installation: As with asymmetrical tires, it is important to follow the tire's rolling direction as indicated by the arrow on the sidewall.
Symmetric:
Symmetrical tires are intended mainly for city or compact cars for short distance driving. The tire is suitable for those looking for good value for money. Mounting: The symmetrical busbar has no mounting direction. You can install and change places without fear of making a mistake.
Typically, the car manufacturer gives recommendations on the choice of tires. There can be several recommended tire sizes, each of which is guaranteed to fit the car without significant losses in handling, smoothness, speedometer readings and durability of chassis components. Alternative tire sizes that can be installed on the vehicle can be found in the vehicle's operating instructions.
RunFlat technology is based on the concept of reinforced tire sidewalls. When a regular tire deflates, it simply sag under the weight of the vehicle, the beads move away from the rim and the sidewalls flatten onto the road, the weight completely destroying the tire within a few kilometers. The reinforced sidewalls of runflat tires hold the tire on the rim and successfully support the weight of the car after a puncture and complete loss of pressure. Moreover, all dynamic vehicle safety systems, such as ABS, ESP, DSC, CBC, etc. remain active. The maximum distance on a flat tire depends on road conditions and vehicle load, about 80 km. The maximum vehicle speed is no more than 80 km/h.
Tires should be inspected regularly. Particular attention should be paid to the condition of the tread, identifying the presence of cuts, cracks and other damage. Tires do not require additional maintenance. You should refrain from applying various aggressive detergents (thinner, gasoline, etc.) to tires.
Tire pressure should be selected based on the vehicle manufacturer's recommendations. This information can be found on the information plate, which is usually located on the gas filler flap or door frame. The information is also displayed in the operating instructions for your car.
During use, your tires lose a little pressure. We recommend checking every month or before long trips.
According to a 2022 Bridgestone study conducted in Irkutsk and Krasnodar, 52% of vehicles tested had incorrect tire pressure.
With reduced pressure, their adhesion to the road surface deteriorates, uneven wear appears, and fuel consumption increases. With increased pressure, depreciation deteriorates when overcoming bumps, and the tire wears unevenly.
Nitrogen is an inert gas, which is dry air without oxygen (air contains about 78% nitrogen). The physical properties of nitrogen reduce the pressure loss that occurs due to the natural permeability of tire materials, but do not completely eliminate it. Unfortunately, there are other ways for leakage: the contact point between the tire and the rim, the valve (nipple), which does not provide an absolute guarantee of maintaining pressure when using nitrogen instead of air when inflating the tire.
We recommend rotating tires during seasonal replacement. This will extend the life of the tire set by ensuring all 4 tires wear evenly.
If the tires are on wheels, then they can be stored in the “lying” position (to save space, the wheels can be stacked on top of each other) or in a suspended state. It is not recommended to store tires on rims in a vertical position. When storing tires without rims, on the contrary, folding the tires horizontally and hanging them is prohibited. It is advisable to store tires without rims vertically (can be close to each other).
We recommend installing newer tires on the rear axle of the vehicle. This is because in the event of an emergency, tires with a deeper tread installed on the rear axle will help prevent the vehicle from skidding or the rear axle being pulled away.
IS IT WORTH BUYING TIRES WITH EXPERIENCE OVER 3 OR 5 YEARS?
Without exception, all leading manufacturers recommend changing tires if they are 10 years old from the date of manufacture. Rubber older than 8 years is considered potentially dangerous in use.
Many offline and online stores offer to buy tires no older than 3-5 years. Subject to proper storage conditions, this is the optimal period for the preservation of wheels without loss of their performance characteristics. You can buy such tires. And its acquisition promises good benefits. As a rule, before the debut of a new collection, a set of tires from previous seasons can be purchased at a very good discount.
