98S on the bus - what does it mean? Full breakdown of load and speed indices

Have you ever looked at the sidewall of a car tire and seen mysterious letters and numbers like 98S? These symbols aren't just random strings: they encode critical information about your tire's capabilities. 98S is a combination of two key parameters: load index (digit) and speed index (letter). Not only the durability of your tires, but also your safety on the road depends on their correct understanding.

Many drivers mistakenly believe that these indices are simply “recommendations” from the manufacturer. In fact they determine maximum permissible operating conditions: Exceeding the limits can cause the tire to explode at high speed or cause the carcass to collapse when overloaded. In this article we will look at what exactly is hidden behind the designation 98S, how to interpret it correctly and why you can’t ignore these numbers when choosing new tires.

You will also learn how to check the compatibility of these indexes with the characteristics of your car, what to do if your car has tires with different indexes, and what consequences may occur if the manufacturer's recommendations are not followed. This information is especially important for owners of used cars where the tires may have been replaced with ones that do not meet the original specifications.

Decoding the 98S index: what the number and letter mean

Designation 98S consists of two parts, each of which carries an independent semantic load. Let's look at them separately to understand what restrictions this marking imposes on the operation of tires.

Number 98 - this is load index (or load capacity index). He points to maximum weightwhich one tire can withstand when driving at the maximum permissible speed. It is important to understand that this weight is calculated for each wheel, and not for the entire car. For index 98 maximum load is 750 kg on the tire. This means that if you have a passenger car with four wheels, the total load capacity of the tires will be 3000 kg (750 × 4). However, this calculation is simplified: the actual load is distributed unevenly (for example, the front axle is usually loaded more heavily than the rear).

Letter S - this is speed index. It defines maximum speed, in which the tire retains its performance characteristics and is safe for use. For index S this limit is 180 km/h. Exceeding this value can lead to overheating of the rubber, delamination of the carcass and even explosion of the tire. It is important to note that the speed index doesn't mean you can drive at top speed all the time - this is extreme limitwhich the tire will withstand under ideal conditions (correct pressure, no damage, normal temperature).

Combination 98S typical for tires intended for city sedans, hatchbacks and middle-class crossovers. Such tires are suitable for most modern cars, where the maximum speed according to technical characteristics does not exceed 180–190 km/h, and the curb weight is distributed within the permissible load.

Load and speed index table: how to read the markings

To better understand where the index is 98S In general classification, let's turn to the standard tables that are used by all tire manufacturers. These tables are universal and regulated by international standards (for example, ETRTO in Europe or TRA in the USA).

Below is load index table (load capacity) for passenger cars. Please note that the values are given per tire:

Load Index	Max. load (kg)	Typical cars
91	615	Subcompact cars (Toyota Aygo, Hyundai i10)
95	690	Compact sedans (Volkswagen Polo, Kia Rio)
98	750	Mid-size cars (Skoda Octavia, Ford Focus)
102	850	Crossovers and minivans (Toyota RAV4, Renault Duster)
106	950	SUVs and commercial vehicles (Nissan Pathfinder)

Now let's consider speed indices. They are designated by Latin letters from A (lowest) to Y (the highest). For passenger cars, the most common indices are from T up to W:

Speed index	Max. speed (km/h)	Example of cars
T	190	Budget cars (Lada Granta, Dacia Sandero)
S	180	City sedans (Honda Civic, Mazda 3)
H	210	Sports cars and premium sedans (BMW 3 Series, Audi A4)
V	240	High speed machines (Mercedes-Benz C-Class, Lexus IS)
W	270	Sports coupes and supercars (Porsche 911, Audi R8)

From the tables it is clear that the index 98S refers to middle class on both parameters. These tires are suitable for most mass-produced vehicles, but are not intended for extreme loads or high speeds.

How to check if 98S tires are suitable for your car

Install index tires 98S Not possible for every car. To avoid safety and legal issues, you should check with recommendations from your machine manufacturer. This data is usually listed in three places:

1. On the rating plate (located on the driver's door pillar, gas filler flap or glove compartment). The permissible tire sizes and load/speed indexes are indicated there.
2. In the instruction manual car (section "Wheels and tires").
3. On original tiresthat were installed at the factory.

If you cannot find this information, please use online tire selection services (for example, on sites Kama Tyres, Nokian Tyres or Michelin). It is enough to enter the make, model and year of manufacture of the car, and the system will show all valid parameters.

What to do if the indexes do not match?

• 🔍 Load index higher than original (for example, instead of 95 it is 98) - acceptable. This is even recommended if you frequently transport heavy loads.
• ⚠️ Load index lower than original — prohibited. Risk of tire destruction when the vehicle is fully loaded.
• 🚗 Speed index higher than original (for example, instead of S there is H) - acceptable, but meaningless for most cars.
• ❌ Speed index is lower than original — prohibited, if the maximum speed of your car exceeds the tire limit.

Example: if your Volkswagen Golf has original tires with index 91T, then install 98S you can do it without any problems - both parameters are higher. But if the original 102H, then 98S will not be suitable due to the lower speed index (180 km/h instead of 210 km/h).

The dangers of ignoring 98S indexes: real risks

Many drivers treat load and speed indices as “recommendations” that can be ignored. This is a dangerous misconception. Exceeding the permissible values leads to irreversible consequences, which can appear at the most unexpected moment.

Consequences of exceeding the load index (98 = 750 kg):

• 💥 Tire carcass rupture - when overloaded, the sidewalls of the tire overheat, the rubber loses its elasticity, and the cord threads break. This often happens at high speed.
• 🔥 Fire in the wheel arch - friction of an overloaded tire against the wheel or suspension elements can cause a fire.
• 🚨 Loss of control - a deformed tire loses its shape, which leads to uneven grip on the road.

Consequences of exceeding the speed index (S = 180 km/h):

• 🌡️ Overheating of rubber — at speeds above 180 km/h, the tire begins to melt, which leads to tread separation.
• 💨 Tire explosion - most likely on the front wheels due to increased load during braking.
• ⚖️ Refusal of insurance payment — if the accident occurred due to inappropriate tires, the insurance company may find the driver at fault.

Critical Fact: According to Research NASA Crashworthiness, the risk of a tire burst increases 5 times when exceeding the speed index by only 10%. For example, if you drive on tires with the S index (180 km/h) at a speed of 198 km/h, the probability of an accident increases from 0.2% to 1%.

⚠️ Attention: If you have installed tires with a speed index lower than the original (for example, instead of an H you have installed an S), then by law you are required to put a sticker on the dashboard warning about the maximum speed. Otherwise, you may be fined for non-compliance of the vehicle with technical standards (Article 12.5 of the Code of Administrative Offenses of the Russian Federation, fine 500 rubles).

Can 98S tires be installed on different axles?

The situation when there are tires with different indexes on the front and rear axles is common. For example, after a puncture or wear, the driver can install one tire with the index on the front 98S, and the old ones remain on the rear axle 102T. Let's figure out whether this is permissible and what rules need to be followed.

Basic rules for combining tires with different indexes:

• ✅ Load Index must be identical on one axis. For example, on the front axle both tires must be 98, even if the rear axle is 102.
• ✅ Speed index may differ, but on the front axle must be no lower than on the rear. For example, if the rear is S (180 km/h), the front can be H (210 km/h), but not vice versa.
• ❌ Prohibited install tires with different load indexes on one axle (for example, 98 and 102 on the front axle).

Why is this important?

• 🔄 Uneven grip — if there are tires with different load capacities on the same axle, the car may “steer” to the side when braking or turning.
• 🔧 Suspension damage — uneven load on the wheels leads to accelerated wear of shock absorbers and wheel bearings.
• 📜 Problems with passing maintenance - during a technical inspection, the inspector may issue an order to eliminate the malfunction.

If you had to temporarily install a tire with a different index (for example, after a puncture), take the following precautions:

• 🛣️ Avoid speeds above 120 km/h.
• 🚚 Do not overload the car (maximum 70% of the permissible weight).
• 🔄 Install a “foreign” tire on the rear axle (if the speed index is lower than the original one).

What happens if you ignore the tire combination rules?

When the load on the axles is uneven, a “yaw” effect occurs - the car begins to randomly change its trajectory at high speed. This is due to the different rolling resistance of the tires. In a critical situation (for example, when going around an obstacle), such a car may lose control. In addition, different speed indices lead to uneven tread wear, which reduces the service life of all tires by 20–30%.

How to choose 98S tires: expert advice

If your car allows the use of tires with the index 98S, when choosing new tires, pay attention not only to these numbers, but also to other critical parameters. Here checklistwhich will help you avoid errors:

What else should you pay attention to?

• 📅 Production date - look for markings DOT XXXX, where the last two digits indicate the week and year of issue. It is not recommended to buy tires older than 5 years, even if they are new.
• 🌡️ Seasonality — the 98S index can be found on both summer and winter tires, but their composition and characteristics are very different. Winter tires with this index usually have soft rubber for low temperatures.
• 🔄 Tread direction - if the tire is asymmetrical or directional, make sure you buy left and right side kits (usually marked Outside/Inside or arrows).

Top 5 tire models with index 98S (according to reviews in 2026):

Model	Type	Average price (per piece)	Features
Michelin Primacy 4	Summer	6 500 ₽	Low noise level, high service life
Continental ContiPremiumContact 6	Summer	7 200 ₽	Excellent grip on wet roads
Nokian Hakkapeliitta R5	Winter	8 100 ₽	Effective at extremely low temperatures
Goodyear Vector 4Seasons Gen-3	All-season	5 800 ₽	Universal for temperate climates
Kama Euro-519	Summer	3 200 ₽	Budget option with good characteristics

When purchasing tires with index 98S also consider climatic conditions your region. For example, for the southern regions of Russia, summer tires with a hard tread are suitable, and for the northern regions, winter tires with soft tires and studs (if permitted by local law).

⚠️ Attention: If you buy tires online, be sure to check what the seller provides warranty card indicating the date of sale. Without this document, claims for defects or hidden defects may be rejected.

Common mistakes when using 98S tires

Even if you have chosen the right tires with the index 98S, errors in operation can negate all their advantages. Here are the most common mistakes that drivers make:

1. Incorrect tire pressure

• ⚠️ Consequences: Reducing the pressure by 0.5 bar increases the load on the tire sidewalls by 20%, which is equivalent to exceeding the load index. For example, a 98S tire at reduced pressure can withstand not 750 kg, but only 600 kg.
• 📉 How to avoid: Check your blood pressure every 2 weeks and before long trips. The optimal values ​​are indicated on the sign in the doorway or in the instruction manual.

2. Ignoring wheel balancing

• ⚠️ Consequences: An imbalance leads to uneven tread wear and increased load on the suspension. Tires with the 98S index are especially sensitive to this, as they are designed for precise parameters.
• 🔧 How to avoid: Balance your wheels every 10,000 km or after any repair (for example, replacing a disc).

3. Use of tires older than 5 years

• ⚠️ Consequences: Rubber loses elasticity even during storage. Tires with index 98S older than 5 years may not withstand the declared load of 750 kg.
• 🗓️ How to avoid: Track production date by marking DOT. If the tires are more than 5 years old, replace them even if the tread looks fine.

4. Using tires out of season

• ⚠️ Consequences: Summer 98S tires lose traction at temperatures below +7°C, and winter tires wear out quickly at +20°C and above. The speed index S (180 km/h) is relevant only with proper seasonal use.
• 🌞❄️ How to avoid: Rotate your tires twice a year (April and October) or use all-season models marked M+S (if allowed in your region).

5. Storing tires in the wrong conditions

• ⚠️ Consequences: Tires stored in the sun or near heat sources will lose strength. A load index of 98 may drop to 95–96 due to frame failure.
• 🏠 How to avoid: Store tires in a dark, cool place (optimally +10...+15°C), hanging them or stacking them in a stack of no more than 4 pieces.

FAQ: Answers to frequently asked questions about 98S tires

Is it possible to drive 98S tires in winter if they are summer tires?

No, this is extremely dangerous. Summer tires at temperatures below +7°C lose their elasticity, which leads to:

• Increased braking distance by 2–3 times.
• Loss of control on snow or ice.
• Risk of rubber cracking when hitting obstacles.

Index 98S on summer tires does not guarantee safety in winter. Use only winter tires that are marked 3PMSF (snowflake against the background of a mountain).

What happens if you put 98S tires on a car that has the original 102H?

This is only permissible if:

• You do not exceed the speed of 180 km/h (S index limit).
• The total weight of the vehicle does not exceed 2800–3000 kg (750 kg × 4 wheels).
• You have stuck a sticker warning about the maximum speed (traffic regulations requirement).

However, keep in mind that when the car is fully loaded (for example, with a trailer), 98S tires may not be able to withstand the load, even if the car’s weight is within the limit according to the passport.

What is the fine for tires not meeting the speed index?

According to Art. 12.5 of the Code of Administrative Offenses of the Russian Federation, operation of a vehicle with tires that do not meet technical requirements is punishable by:

• Warning or fine 500 rubles (for the first violation).
• Fine 2,500 rubles upon repeated violation.

In addition, the inspector may prohibit further movement until the malfunction is eliminated (Article 27.13 of the Administrative Code).

Is it possible to install 98S tires on the front axle if the rear axle is 102T?

Yes, but only if:

• Front axle speed index not lowerthan on the back. In your case S (180 km/h) is lower than T (190 km/h) so it is prohibited.
• If there was an S on the rear axle and an H on the front axle, this would be acceptable.

Uneven speed indices along the axes lead to unstable vehicle behavior at high speeds.

How long will 98S tires last?

Service life depends on several factors:

• Operating conditions: 40–50 thousand km with quiet driving, 20–30 thousand km with aggressive driving.
• Pressure: With the right pressure, the service life increases by 15–20%.
• Seasonality: Winter tires wear out faster than summer tires due to the soft rubber.
• Balancing: Imbalance reduces service life by 10–15%.

On average, 98S tires last 3–5 seasons (for summer) and 2–4 seasons (for winter) subject to all rules.