S speed rating has a maximum speed of 112 mph compared to T speed rating of 118 mph. S speed rating is better at colder conditions and has more tread life. However, T speed rating tires are better at handling and driving at warmer road conditions. Along with that, the price is relatively higher for S speed rating tires.
With that cleared out, you still need to know about the significance of speed rating, difference between higher and lower speed rating, and if you can mix these two tires or not. To know more, let’s get started.
Difference Between S and T Speed Rating
Let’s go straight to the comparison table between S and T tire speed rating.
|Factors||S Speed Rating||T Speed Rating|
|Maximum Speed||112 mph or 180 km/h||118 mph or 190 km/h|
|Handling||A bit Difficult in handling due to harder rubber compound||Better at handling due to softer rubber compound|
|Driving Conditions||Better at Snowy Roads||Better at Warmer Roads|
|Tread Life / Longevity||Better longevity||Good longevity|
|Vehicle Compatibility||Minivans, Light Trucks, Sedan||Minivans, Light Trucks, Sedan|
|Price||$70 – $200||$85 – $200|
First, the main difference between the two speed ratings is in the maximum speed it can endure. S speed rating can face up to 112 mph or 180 km/h whereas T speed rating can face up to 118 mph or 190 km/h. As observed, the difference between the two is not that high when it comes to the maximum speed.
Summary: S speed rating has the maximum speed of 112 mph and T speed rating can endure a maximum of 118 mph.
When it comes to handling, typical consideration is breaking distance, cornering and steering response i.e how efficiently the tire can act on the driver’s request. Normally, a tire that is made with a softer compound tends to show better grip and overall handling capability.
Among the two options, T type speed rating is made with softer rubber compound and more stiffer construction. This means it can get proper handling compared to S speed rating tires.
Summary: T type speed rating has better steering response and cornering stability.
Normally, lower speed rating tires are better at winter conditions and higher speed rating tires are the better choice at warmer conditions. Even though the difference between the two speed ratings is not that high, S rating is relatively better at colder conditions but T rating is slightly better at warmer conditions.
Summary: Normally there won’t be a major difference between the two speed ratings but S type speed rating is slightly better at colder conditions and T type at warmer conditions.
Typically, the tread life of tire depend on its material and other external factors like the load, inflated pressure, and road conditions. However, there is a slight difference in tread life between S and T speed rating.
Normally, higher speed rating tires come with lower tread life. This is because of the stiffer sidewall construction of the tires. So, T speed rated tires will have stiffer sidewall, better cornering ability but lower tread life. Comparatively, S type tires will have better tread life. However, this difference will be quite minimal since the speed rating difference between S and T is not that high.
Summary: S speed rating tires have better tread wear ability compared to T type speed rating tires because of the rubber compound in it. But remember, speed rating is not the major deciding factor for tread life.
Both the tire speed rating types are compatible for use in sedan, minivans and light trucks. This is particularly the tread pattern and sidewall construction that makes them compatible for both on-road and off-road conditions.
As observed from the table, for two tires with 245 mm section width and the tire aspect ratio of 70, the cost is higher for S type speed rating.
Following are the price range for different size tires of the vehicles using S and T speed rating tires.
|Vehicles||S Speed Rating||T Speed Rating|
|Sedan||$70 – $145||$85 – $95|
|Light Trucks||$105 – $200||$100 – $200|
Summary: Through comparison, it can be observed that despite their small difference there is a major variation in performance especially in maximum speed and handling of the tire.
Can You Mix S and T Speed Rating On Your Vehicle?
Yes, you can mix S and T speed rating on your vehicle but you should not do it. This is because mixing tires with different speed ratings will make it difficult for you to handle your car. Although there is not much difference between the speed rating of S and T, there is a slight difference in the tread geometry.
Now, if you want to mix S and T speed rating anyway, then always put the lower rated (in this case S rated) tire in the front axle and the purpose is to avoid oversteering issues. Finally, don’t drive above the recommended speed limit of S rated tires.
Does a Higher Speed Rating Mean a Better Tire?
No, a higher speed rating does not always mean the tire is better. This is because as the speed rating is increased, the rubber material of the tire gets softer whereas the tire carcass gets stiffer. The problem with this is a decrease in tire tread wear and flexibility.
Now, it doesn’t mean that higher speed ratings have no inherent benefit. In fact, these tires are more suited for its grip and handling abilities. This is why higher speed rating tires are preferred for performance cars which require better control and grip.
Speed Rating: Why Are They Important?
Speed rating is the maximum speed the tires in which your cars can carry the entire load without any problem for a long period of time in ideal conditions. It must be clear at this point that the speed rating is a major performance criteria for your tires.
Of course, it is an estimation of how much heat the tire can carry and if you cross the speed rating occasionally your tires won’t be affected highly but if you cross the speed rating on a regular basis then you risk your tires getting blown up from heat buildup.
Again, speed rating is also significant in deciding the specific performance. For example, High speed rated tire is bad for winter because it is made with a softer rubber compound and its construction is more stiff. Tires need to be more flexible for optimal performance in winter and that’s why it is better to choose a lower speed rating tire for winter.
Speed Rating Chart
Now, the following is the speed rating chart for different types of tires.
|Rating||Maximum Speed in mph (kmh)|
So, from the table the speed range can be seen in both mph and kph.
Summary: Speed rating is an important performance criteria for tires and it helps to show how much speed a tire can sustain. There are different speed ratings for different types of vehicles.
Is 130 mph Applicable For S Speed Rating?
No, for S speed rating the maximum speed that it can sustain is 112 mph. However, the H speed rating is the one for 130 mph. S type speed rating is mainly for sedan, light truck and minivans whereas H speed rating is used for passenger cars, sports cars and coupes.
Can You Fit Tires With High Speed Rating On Your Car?
Yes, you can fit tires with a high speed rating on your car. But how high of a speed rating depends on the type of car you are driving. Of course, it is not recommended to use the tire rating for an exotic sports car on a sedan. Always make sure to look for the tire size and tread type while you fit the tire in your car and it is recommended that you use the exact speed rating on your car.
Can You Fit Tires With Low Speed Rating On Your Car?
Yes, you can fit tires with low speed ratings on your car as long as you don’t cross the recommended speed limit. Lower speed rating means that the tires can endure lower speed. Now, let’s assume you put a tire with Q speed rating i.e 99 mph and your car can go up to 130 mph, then you need to ensure that you don’t go above 99 mph on a regular basis.
Alright, with that hopefully you are clear on everything about S VS T Speed rating. Make sure to check the tire rating for your vehicle and keep in mind the difference between the two ratings. Finally, keep in mind about the effects if you mix the tires of two different speed ratings.