Tires Buying Guide: Speed Rating Explained (2024)

Tires Buying Guide: Speed Rating Explained (1)
A speed rating is a letter or a combination of a letter and a number which implies to what extent the tire successfully dissipates heat. Exceeding that speed will make the tire performance differ from the initial specifications. This may lead to anything from temporary traction loss to rapid deflation and irreparable damage.
The rating doesn’t mean you can safely drive at the maximum speed for a long time however, especially in extreme weather conditions. You can only maintain that speed for about 10 minutes before the tire overheats and its performance deteriorates.

Where to Search for a Speed Rating?

You can find the rating in/on the:

  • Owner’s manual.
  • Tire sidewall.
  • Driver’s side door jamb.
  • Glove box door.
  • Gas tank hatch.

The owner’s manual has all the information you need about the recommended tires for your vehicle. Information placards on the door jamb, glove box door, and gas tank hatch are for the cases when you need a quick recommendation while on the go. As for the tire codes, there you will see a speed rating for the particular tire. There will be no vehicle-related recommendations, so it would be wise to consult both the vehicle manufacturer’s suggestions and the markings on the tires.

How Speed Rating Works

How Does a Tire Get a Rating?

Tires get the ratings according to the results of the tests where speeds and loads are simulated. In brief, a specialist inflates a tire to the recommended pressure and puts it into a large drum. It then rotates the tested tire, increasing speeds by 6.2 mph every 10 minutes. As the rotation reaches the estimated maximum speed for the tire, the specialist checks whether the tire keeps its integrity.
The conditions for the tests are perfect, so special road/environment-related conditions aren’t included. That’s why the actual maximum speed of the tire is often lower than its speed rating. If the tire is even slightly underinflated, or the vehicle is overloaded, or it’s boiling hot outside, the ratings may become irrelevant.

What Does the Speed Rating Influence?

Aside from speed, this rating influences:

  • Heat build-up.
    Tires with lower ratings flex harder under pressure, which causes heat build-up. It may cause a wide range of issues, from premature aging to tire failure and immediate blowouts. Tires with higher ratings have special compounds and reinforcements that help avoid excess heat build-up.
  • Braking.
    Low-rated tires will stop for a longer amount of time, as they change shape and squirm during hard braking. Take two tires with the speed ratings S and V and ride them at 100 km/h. As the V tire comes to a full stop, the S tire still goes at about 25 km/h. The difference in braking distance turns out to be about 4 m (about 13 ft) in this case, but when talking about emergency braking, this difference will play a big role.
  • Cornering grip.
    Just as a low-rated tire will deform when braking, it will when cornering. The contact patch area also changes its shape during hard turns, making the grip worse. Heat-up may follow and add to the condition.
  • Steering responsiveness.
    Less flex and the overall construction of the tires with a higher speed rating will make your vehicle more responsive. So, you won’t have to turn the steering wheel more and wait for the reaction of your tires. Lower ratings also perform well and are responsive, but only at the speeds they are designed for.

Speed ratings are often called performance ratings, as they influence most aspects of traction and responsiveness. For better speed handling, the construction of the tire has to be improved. That’s why high-rated tires are considered higher in quality. Low-rated tires are still useful for vehicles with capacities matching those tires. That’s why it isn’t recommended to buy a sports low-profile tire with a Y rating if you need a regular H-rated tire.

How to Read A Speed Rating

Nowadays, the system uses the letters A to Z and numbers 1 to 3 for the “A”. Each letter or letter and number combo represent a certain speed, as shown in the table. As the alphabet goes forward, the speeds become higher, mostly. You can guide yourself using a table or just remember the letter specified in your owner’s manual.

Tires Buying Guide: Speed Rating Explained (2)

Here are some of the irregularities to know about when reading speed ratings:

  • The “H” rating is between the “U” and the “V”, not after the “G”. The speed of the rating corresponds to its position.
  • There are no “I”, “O”, and “X” ratings. There are also charts that exclude the “P” rating.
  • The lowest ratings are “A1”, “A2, and “A3”.
  • For the “W” and “Y” ratings, some manufacturers include “Z” into the tire side code after the aspect ratio.

NOTE: The maximum speeds seem unusual in mph. This is because the system of speed rating was developed in Europe, where speed is in km/h.

Tire Type and Speed Rating

The ranges are the following:

  • All-season tires are usually of the “S” and “T” ratings.
  • Performance all-season tires are of the “H” and “V” ratings.
  • Ultra-high performance tires are can be of the “ZR”, “W”, and “Y” ratings.
  • All-season truck tires are of the “S”, “T”, and “H” ratings.
  • All-season SUV (sport utility vehicles) tires are of the “T” and “H” ratings.
  • All-terrain off-road tires can be of the “L” to “S” ratings.
  • Winter/snow tires are of the “Q” rating and higher.
  • Performance winter tires are of the “H” rating and higher.
  • Truck winter tires are usually of the “S” rating.
  • Temporary spare tires are usually of the “M” rating.

Vehicle Type and Tire Speed Rating

Here are the correlations between the ratings and types of vehicles:

  • Family vans and sedans will go well with S- or T-rated tires.
  • Sedans and coupes will get enough speed from U-rated tires.
  • Sport sedans and coupes can start with H- or V-rated tires.
  • Exotic sports cars will work great with the high-speed capable W-, Y-, and (Y)-rated tires.
  • Heavy-duty light trucks will go with R-rated tires.

Before choosing a tire according to such examples, consult your owner’s manual for suggestions from the manufacturer.

FAQ on Speed Ratings: Everything You Need to Know

What Speed Rating Should I Choose?

The most appropriate variant is within the owner’s manual or using the same size, load, speed, etc. as your original set. However, you can go a bit higher if you have extreme weather conditions in your area, or if the roads are bad, etc. Downgrading tires is strongly not recommended, as the maximum speed and performance will degrade, endangering you and the vehicle.

Can I Mix Tires with Different Speed Ratings?

It isn’t recommended, however, if you have to use different tires for some time, mount them in pairs on the axles. The pairs must be of the same rating, and it’s the best if the lower-rated pair is on the front axle. This will help avoid oversteer. Remember that in this case, your vehicle will be limited according to the rating of the lower-rated tires.

Tires Buying Guide: Speed Rating Explained (3)

What Speed Ratings Are the Best for My Off-Road Vehicle?

For regular off-road vehicles, speed isn’t the first priority – traction is. Usually, L-rated tires are recommended, but it may be higher depending on the model of the vehicle. Off-road tires are reinforced no matter the rating. So, unless you have a sports truck and need more speed, stick to the manufacturer’s recommendations.

Are Higher Speed Indexes Better?

Within the most appropriate range for your type of vehicle – yes. However, it depends on your needs. If you often drive loaded at highway speeds and it’s hot in your area, you may want to consider a higher rating. But if you drive in a city mostly, where there are speed restrictions, you may want to stay closer to the bottom of the suitable indexes. Tires with higher speed capabilities usually cost more, so if you don’t need them, there’s no sense in spending more.

Is the Speed Rating Important for Winter Tires?

Yes, it’s important for any tires, but winter ones are an exception from the “no downgrade” rule. You can install tires with a slightly lower rating than your original tires. This is because in winter, people usually drive at slower speeds, so these capabilities become less relevant. The “Q” rating is the most regular and frequently used in snow tires.

Tires Buying Guide: Speed Rating Explained (2024)

FAQs

Tires Buying Guide: Speed Rating Explained? ›

In short, it's the fastest speed a tire can handle before it no longer performs as designed. The higher the speed rating, the better control and handling you'll have at higher speeds. The speed rating system was developed to help control the safe performance of tires at standardized speeds.

Does speed rating matter when buying tires? ›

One of the most important aspects of any tire is its speed rating. The wrong tires with a less-than-adequate speed rating for your vehicle can cause safety issues, including tire failure and a loss in fuel efficiency.

What speed rating do I want for my tires? ›

Tire Speed Rating Chart
Speed SymbolMaximum SpeedVehicle Type
T118 mphFamily Sedans & Vans
U124 mph
H130 mphSport Sedans & Coupes
V149 mphSport Sedans, Coupes & Sports Cars
10 more rows

Which is better, T or H speed rating? ›

H-Rated Tires: This is a perfect, average tire for most sedans and commuter vehicles. It might not seem to fit in our chart, but the tire speed rating “H” is rated for up to 130 mph. T-Rated Tires: This tire is often recommended for family sedans and vans. It's rated for up to 118 mph.

Do H or V rated tires last longer? ›

Sticking with H-rated tires comes at a cost. While we found prices are similar to S- and T-rated tires, H-rated tires didn't last as long in our treadwear test--an average of 49,180 miles, versus 61,080 for our S- and T-rated tires. V-rated tires had an even shorter tread life of 48,260 miles.

Is it OK to get lower speed rating on tires? ›

You can always go up in performance rating, but you can never downgrade or you'll compromise the handling and safety of your vehicle. Note: One tire size could come in multiple speed ratings.

Should all 4 tires have same speed rating? ›

Always choose the speed rating that corresponds to your vehicle manufacturer's specifications, and be sure all four tires have the same rating.

What are the most common tire speed ratings? ›

Speed Rating H

As mentioned above, the “H” speed rating does not appear after “G” but instead between “U” and “V”. This rating represents a maximum speed of 130 mph, or 210 kph, and is most common;y found on sports sedans and coupes.

Does higher speed rating mean better tire? ›

A tire's speed rating indicates the optimal speed that the tire can safely maintain over time. In short, it's the fastest speed a tire can handle before it no longer performs as designed. The higher the speed rating, the better control and handling you'll have at higher speeds.

Can I go faster than my tires speed rating? ›

If you equip your vehicle with tires of different speed ratings, the lowest tire rating determines your vehicle's safe top speed. However, you should always obey legal speed limits, regardless of your tire speed rating. You can find your tire's speed rating by reading the size code on the tire's sidewall.

Can I mix T and H tires? ›

I would recommend against mixing speed ratings, since there's a good chance there's a difference in grip levels between the T rated tires and the H rated tires, this can cause unpredictable handling characteristics in some situations. Tires and brakes are two areas where you should never cut corners IMHO.

What happens if you go over your tire speed rating? ›

What happens if you exceed your tire's speed rating? If you drive faster than the rated speed for your tires you are risking damage to the tires that could cause safety and performance problems down the road.

Does tire speed rating affect ride quality? ›

In actual practice, however, tire speed ratings do make a difference, not only in regards to speed but also in regards to ride comfort, traction, treadwear and cornering ability.

Are 15 year old tires still good? ›

Any tire over ten years old is too weak to ensure safe driving. At this age, it's imperative that you replace your tires. For your safety, we will not service any tires aged 10 years or older.

Do higher quality tires last longer? ›

The durability of the tires is one of the most important factors in determining whether you will get your money's worth. After all, tires that are more durable will last longer, thereby saving you money on new tires. Durability is determined by a number of criteria. If a tire has softer rubber, it will perform better.

How many miles is a 600 treadwear rating? ›

By multiplying the treadwear rating of a tire by 100, you can get its estimated tread life length. A 600 treadwear rating indicates that the tire is good for 60,000 miles. However, this is just an estimate as driving styles and road conditions can greatly shorten a tire's service life.

What happens if you go over the speed rating on tires? ›

Running a tire at speeds higher than its rating can shorten the tire's life and potentially lead to a tire damage which could result in an accident, so it is important to follow the manufacturer's speed rating recommendations when you are choosing tires.

Can you install tires with different speed ratings? ›

It is not recommended to fit tires with different speed ratings. If tires with different speed ratings are installed on a vehicle, they should be installed with like pairs on the same axle. The speed capability of the vehicle will become limited to that of the lowest speed rated tires. Obey all speed limits.

Can I use zr tires instead of r? ›

R indicates that the structure is RADIAL. So, VR indicates that the tyre has a RADIAL structure and a speed index equal to V. There is therefore no difference between a ZR or an R tyre with the same speed index.

What is the speed rating on tires for insurance? ›

The speed rating of a tire is important. The letter symbolizes how much speed your wheels can safely handle. Find out what your rating is and don't go any faster than that. If you are getting ready to hit the road again, make sure you have the car insurance coverage you need.

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