The speed rating system was developed to help control the safe performance of tires at standardized speeds. A tire’s certified speed rating is given a letter from A to Z, ranging from 5km/h (3mph) to above 300 km/h (186 mph) which however does not indicate the total performance capability of a tire.
For example, ‘H’ rating is classification for a high speed tire, ‘V’ for a very high speed tire and ‘S’ for a standard tire.We will be learning all about how to read tire speed rating in this article.
A typical tire speed rating with its corresponding speed limit is as shown below;
Speed-rating Maximum speed
L 75 mph 120 km/h
M 81 mph 130 km/h
N 87 mph 140 km/h
P 93 mph 150 km/h
Q 99 mph 160 km/h
R 106 mph 170 km/h
S 112 mph 180 km/h
T 118 mph 190 km/h
U 124 mph 200 km/h
H 130 mph 210 km/h
V 149 mph 240 km/h
Z 149+ mph 240+ km/h
W 168 mph 270 km/h
Y 186 mph 300 km/h
(Y) 186+ mph 300+ km/h
As much as tire selection is important for your driving safety and proper handling of your car, the tire rating system makes it easier for you to compare different tires and pick the right ones depending on your type of car, usage, location and terrain.
The tire speed rating indicates the maximum speed at which it can safely carry a given load at a specified inflation pressure and it’s just a guide, and not the rule in defining tire’s performance.
IMPORTANCE OF TIRE SPEED RATING
The letter designation on a tire rating shows the optimum speed for which the tire is rated. The tire size and rating looks like 225/50R16 89H, where the ‘H’ designates the speed rating.
The speed rating indicates the maximum speed at which a tire can be safely driven thereby helping you to determine your speed at any given time.
Speed ratings range from N (87 mph) up to Y (186 mph). High-performance super cars such as Ferrari and McLarens sometimes have Z-rated tires.
Speed rating on tires help driver to choose correctly having the type of vehicle they drive in mind. At higher speeds the wheels turn faster and more heat is generated.
So, it’s important you choose tire that can cope with the speed of your car because running such car with a low speed-rating tire is highly risky.
WHAT IS A ‘H’ RATING
‘H’ rated tires are rated for a maximum speed of 130 mph. For normal driving conditions the H-rated tire will provide a more comfortable ride. Both H- and V-rated tires are considered to be performance-touring tires. However, H-Rated tires have shorter life spans compare with other ratings.
WHAT IS A ‘V’ RATING
The ‘V’ rating is the fastest rating which has up to 149 mph as limit. Supporting running at higher speeds, V-rated tires will have a stiffer sidewall and slightly firmer ride than H-rated tires with better handling. Both H- and V-rated tires are considered to be performance-touring tires.
WHAT IS A ‘T’ RATING
A ‘T’ rating indicates that the tire is approved for speeds up to 118 mph (190 km/h) under optimal conditions. ‘T’ ratings are most associated with standard touring tires and everyday passenger vehicles like family sedans and minivans.
WHAT IS A ‘S’ RATING
An ‘S’ speed rating indicates the tire has been approved for speeds up to 112 mph (180 km/h) under optimal conditions. Everyday passenger vehicle tires can be ‘S’ speed rated, but S tires often prioritize specific performance or function.
WHERE DO I FIND MY TIRE SPEED RATING AND HOW DO I UNDERSTAND ITS MEANING?
You can find your tire speed rating in a number of places, typically in the owner’s manual, driver’s side doorjamb, glove box door, and gas tank hatch. Recent standardization has changed so all ratings except “Unlimited ZR” indicates the speed symbol and load index as part of every tire’s service description on the tire’s sidewall.
Speed rating is located as the last item in the character sequence in the tire’s size code. For example in this tire code: “P205/60R16 82S,” ‘S’ is the speed rating. To view the tire size code for your current tires, just look at the sidewall at the end of the tire size.
The sidewall has a lot of information such as the depth of the sidewall, the speed rating, diameter of the wheel and width of the tire itself.
To read and decode the speed rating on your tire, follow this step. On the tire’s sidewall for a ‘V’ rated tire you have it written as: 205/60R15 91V: which is ‘205’ – Section width in millimeters, ‘60’ – Aspect ratio, ‘R’ – Radial construction, ‘15’ – Rim diameter in Inches, ‘91’ – Load Index Service Description and ‘V’ – Speed Symbol.
CAN I PUT A LOWER SPEED RATING ON MY TIRE
No. Putting lower speed ratings on your tire can affect the way you drive and reduce your maximum safe speed. If you equip your vehicle with tires of different speed ratings, the lowest speed rating will determine your vehicle’s maximum speed of which the tires can safely handle.
DOES TIRE SPEED RATING MATTER AND HOW DOES IT AFFECT MY CAR
The speed rating is as important as your choice of tires. The speed rating tells you the speed the tire can safely maintain over time.
A higher speed rating usually means you will have better control and handling at higher speeds and that the tire can take the extra heat. As a general rule, tires with higher speed ratings also handle better at lower speeds.
When it comes to tires and the safety of those inside the vehicle, there is a great deal of caution to take. All tires have a speed rating, and those ratings determine how fast the vehicle can safely travel on those tires, from about 75 mph to 186 mph.
If then unknown to a driver, driving a low speed-rated tire on higher-than-approved limit put the driver and others in the vehicle as high risk.
CONCLUSION
To be at the safest level on the wheel at all times, driving with approved speed as specified on the chosen tire is necessary.
Apart from getting the right tire for your vehicle and understanding how to manage the tires, limiting your usage in accordance with manufacturer’s recommendation will go a long way in keeping you and your vehicle safe.
It is important to note that speed ratings only apply to tires that have not been damaged, altered, under-inflated or overloaded.
Additionally, most tire manufacturers maintain that a tire that has been cut or punctured no longer retains the tire manufacturer’s original speed rating, even after being repaired because the tire manufacturer can’t control the quality of the repair.
We hope now you know more about how to read tire speed rating, if you have a question or comment drop it in the box below, we will be glad to hear from you.
