We will explain when to replace tires with studless tires, criteria for judging service life, and inspection methods. The lifespan of studless tires is generally said to be about 3 to 5 seasons, but deterioration progresses regardless of the frequency of use. Inspect the tire before replacing it.
Studless tires → when to replace summer tires?

It seems that the time to change from studless tires to summer tires is generally from the end of March to the beginning of April.
The performance of summer tires can be demonstrated at temperatures above 7°C.It is said that it is a guideline for replacement when the outside temperature does not fall below 7°C. In northern Japan and mountainous areas, please refer to the remaining snow on the roads and the weather forecast.
also,The service life of studless tires is 3 to 5 years from the date of manufacture.It is said. Tires are made by adding various additives to rubber, which is the main component, to adjust strength and softness. Therefore, it has the characteristic of degrading its performance as the components change and deteriorate over time.
Especially for studless tires, the softness of the tread surface is directly related to the performance on ice, so the storage method for the period when not in use is important to maintain the condition. When switching to summer tires, check the life of the tires.
It is NG to wear studless tires!
Summer tires and winter tires (studless tires) that you change every year. The danger of driving on snowy roads with summer tires is well known, but it is also very dangerous to wear studless tires (= keep wearing them all season).
Studless tires are characterized by softer rubber than summer tires in order to run on snowy roads without slipping. for that reason,On dry roads, the braking distance will be longer and braking will be less effective.
Furthermore, the grooves of studless tires tend to collect water,Increased risk of slipping in rainy weatherI do. In addition, driving on studless tires leads to deterioration of fuel efficiency of the car.
Of course, it is NG to use it as a summer tire because the tread is reduced and it can no longer be used as a studless tire! For safe driving, wear tires suitable for the season.
Studless tire VS normal tire brake test
This is a video of a comparison experiment between studless tires and normal tires. Although this test is only for braking, you can see the dangers of using studless tires in the summer, so please check it out.
We will explain when to replace tires with studless tires, criteria for judging service life, and inspection methods. The lifespan of studless tires is generally said to be about 3 to 5 seasons, but deterioration progresses regardless of the frequency of use. Inspect the tire before replacing it.
Three criteria for judging the life of studless tires

Studless tires, which are made of softer rubber than summer tires, tend to wear out more easily.
Studless tires with shallow treads due to wear cannot drain snow and water from the treads, which significantly reduces the driving performance of the vehicle.
In addition, when the rubber of studless tires hardens due to deterioration over time, the grip performance on icy roads drops dramatically, which is extremely dangerous.
Although it depends on the conditions of useThe life of studless tires is generally about 3 to 5 seasons.It is said that However, since it is only a guideline for the replacement period, it is important not to miss frequent inspections.
There are three criteria for judging the life of studless tires.
- Check the tire groove (slip sign) and platform!
- Check the week of manufacture of studless tires!
- Pay attention to deterioration of rubber for the life of studless tires!
Basically, the criteria are the same as for normal tires. What you want to be careful about is the platform that is unique to studless tires. Be careful when looking at the remaining grooves.
For more information on the criteria for judging when to replace tires and their service life, see the article below.
Things to do before storing studless tires
Check tire condition
Before storing, make sure that the removed studless tires can be used next season. Carefully check to see if there are any grooves left, if there is any abnormal wear, if there are any cracks in the sipes or sidewalls, and if there are any nails or bolts stuck in them.
remove dirt
Dirt on studless tires after driving contains oil and other impurities, which lead to deterioration of the tires. Deterioration can be prevented by thoroughly removing dirt from tires before storage. Tire wax is also oil that causes deterioration, so be sure to wash off the tire wax thoroughly with water.
let it dry properly
Moisture left in washed tires also leads to deterioration. Moisture adhering to the tire causes deterioration of the rubber and rusting of the internal wire, which reduces the strength of the tire. It is best to dry and store washed tires in the shade out of direct sunlight.
put on vinyl
It is also important to cover it with plastic to prevent dust and dirt from adhering to it during storage. The oil contained in the rubber of the tire volatilizes over time, which leads to deterioration, so cover the tire with a plastic bag or stretch film. By keeping it out of the air as much as possible, you can minimize the volatilization of oil.
Optimal storage method and location for studless tires

For indoor storage, store in a cool, dark place with good ventilation.
The best place to store studless tires is a cool, well-ventilated place that avoids UV rays and heat.
However, tires are designed for outdoor use, so they don’t need to be managed as strictly as paintings. A sheltered location out of the sun will suffice. A location that is not exposed to direct sunlight, such as a garage or warehouse, or a living room is ideal.
Oxygen in the air also oxidizes the resin, which is a small cause of tire deterioration. For best preservation, use a product that vacuum packs your tires.
Precautions when storing outdoors
If you cannot secure an indoor storage space, cover the tires with a cover or case to protect them from direct sunlight and ultraviolet rays. In particular, ultraviolet rays are highly aggressive to resins, and plastic products can become tattered after being left outdoors for just a few months.
If you store it in the open or on the balcony on the first floor, you need to be careful of theft.
Air pressure when storing studless tires
Even in the sense of weakening the stress of tires that expand with air pressure, it is better to remove the air inside the tires to some extent when storing studless tires. Set the air pressure to the lowest level that will keep the tire shape. If the specified air pressure is 220kPa, it is better to deflate to about 150kPa.
In addition, filling the tires with nitrogen gas not only improves noise and fuel efficiency, but also has the effect of extending the life of the tires.
How to store studless tires

The rubber of studless tires is soft and easily deformed. Therefore, care should be taken when storing.
In addition, the components of the tires may bleed black from the tires that are placed, resulting in stains that cannot be removed. When placing the tire, do not put it directly on the floor, but put a thick cardboard or the like on it.
When storing tires only[Vertical]
When storing tires only, place them vertically. If you stack tires without wheels on top of each other, the weight of the tires will crush and deform them.
When storing with wheels[horizontal]
If the tire has a wheel, put it on its side. If a tire with a wheel is placed vertically, the weight of the wheel will crush the tread surface.
However, since the sidewall is the weakest part of the tire structure, stacking too many tires horizontally can damage the tire.
The most ideal way is to use a tire rack that supports the center of the wheel hub and place it so that no external force is applied to the tire.
Studless tire recommended storage goods
I picked up storage goods full of ideas to keep tires in good condition. Let’s aim to maintain the performance of studless tires by using these goods.
pallets under tires
Wooden slats may corrode in some places and are not suitable for long-term use. Plastic pallets combine high weather resistance and durability. The size is also perfect for tires.
tire vacuum pack
It is an excellent product that can be used to vacuum-pack tires, like using a vacuum cleaner to compress a futon. It protects tires from dust and moisture, and shuts out oxygen. There is an adaptation size, so let’s check the tire size.
ideal tire rack
It is an ideal tire rack that does not put a burden on the tires because it is held in the center hole of the wheel. It is structurally unstable, so please be careful when moving it.