I have been to tire shops – reputable ones – and have had one tire changed. At no time when I was either talking to a fitter or online was I asked about the speed rating of my current tires.
Many others say it’s advisable to have all the same speed tires.
In this article, we’ll examine what a speed rating means in reality and whether the advice to have all the same ratings is just a way to get you to part with more money or not.
If you’re involved in an accident with different speed ratings than recommended for your car, you may have difficulty getting a payout.
Before we get into the details and explore whether common tire ratings can be mixed, as a general rule:
You can have tires of different speed rated tires if you don’t exceed the maximum speed allowed on the lowest-rating tire. A lower-rated tire may be less grippy and less responsive, however.
Can I Mix Speed Rating Tires?
The lowest rating is L which is rated up to 75 mph – so five mph more than can be driven anyway. These tires are not sold as road tires and are limited to off-road vehicles. Of course, you could buy these online, but no tire shop would fit these on a road car.
Generally, the tires available to you are in the range of H through to Q.
A Q-rated tire has a speed rating of 99 mph, while H has a top rating of 130 mph.
Another important consideration is the load index
If you must combine speed ratings, which we do not recommend, place the lower-rated tires on the front axle irrespective of whether your car is front, rear, or four-wheel drive. This is done to prevent an oversteering situation.
Please remember that all tires must be suitable for the vehicle, and you should not drive faster than the speed rating of your lowest-rated tire.
Can I Mix S and T Rated Tires?
Both ‘S’ and ‘T’ rated tires are common rated tires found on many sedans. Both are rated to be good for speeds over 100 mph. – ‘S’ rated tires are good for 112 mph, and ‘T’ rated tires have a speed limit of 118 mph.
As you can see a very small difference. Remember that your tire won’t necessarily blow when you hit the higher limit of the tire. It may be good for another ten mph – but of course, that is never recommended.
No one apart from the tire manufacturer knows at what speed their tires failed during testing.
It’s reasonable to assume they have allowed some leeway in the rating.
You’ll unlikely be traveling anywhere near the speed rating itself.
So the answer is yes, you can but with some caveats. Make sure the load rating of the tires is the same. This is the amount of weight each tire has been tested too.
Never exceed the maximum speed of the lower-rated tire.
The lower-rated tire may not be as good in harsher weather as the higher-rated tires, but the difference should be hardly noticeable.
Can I Mix T and H Rated Tires?
A ‘H-rated tire has a top speed of 130 mph, and a T-rated tire has a top speed of 118 mph. If the tire load rating is correct for your car, you could use both of these tires on your car at the same time.
It’s not recommended, though, as speed rating is more than a speed indicator. It is also a sign of improved grip and performance too. You may feel that unless you get close to the top speeds of the tires, you shouldn’t encounter any issues apart from a decline in performance.
Can I Mix V and H Rated Tires?
An ‘H-rated tire is rated at 130 mph, while a ‘V’ rated tire has a top speed of 149 mph. You could put both of these tires on your vehicle simultaneously if the load rating is appropriate for your vehicle. It is not advised, however, because the speed rating is more than just a speed index; it is also a sign of enhanced grip and ability.
Unless you go close to the tire’s top speeds, you shouldn’t have any problems other than a drop in performance from the ‘H’ rated tire compared to the ‘V.’
The decreased performance may show itself in cold weather and less grippy in extreme turning. Both of these should be negligible in normal driving behavior.
Can I Mix W and V Rated Tires?
A ‘W’ rated tire is good for speeds up to 168 mph – way in excess of any speed limit, while a ‘V’ tire has a top-end rated speed of 149 mph. Quite a speed difference of 19 mph. However, it’s unlikely that you’ll be traveling more than 149 mph, so the speed is not a concern.
If we ignore the speed limits of both tires, are there any other reasons why these tires shouldn’t be mixed?
The load index should be the same for all tires. If that is the case, the only difference is the tire’s handling at the extreme of its range.
You may notice that the V-rated tire isn’t quite as grippy as the ‘W’ rated one.
Tire manufacturers use slightly different compounds on their tires too. If you are mixing speed ratings, it’s better to use tires from the same manufacturer.
All in all, it’s better to have all four tires at the same speed rating where possible and certainly if you expect to get to the higher end of the speed for which the tire is rated.
Are Different Speed Ratings More Expensive Than Others?
Yes, they are, but not by much. A higher-rating tire has been manufactured not only at a higher speed but also to give better grip and all-around performance. The tread pattern is often different, and the rubber compound is tweaked slightly too.
That said, the price difference between tires rated higher or lower than the other would only equate to a few dollars.
This is because the difference in performance and maximum allowable speed is slightly higher.
What Happens If I Exceed The Speed on The Tire Rating?
Tires are tested rigorously. If you exceed your tire’s speed rating, you may still be okay. Tires are tested beyond the speed rating given – a safety net – so if a driver inadvertently exceeds the tire rating speed for a short time, the tire is unlikely to blow immediately.
Tire manufacturers don’t publish the safety zone information as they don’t want drivers accelerating over the rated speed. The tires didn’t necessarily fail above the rating given.
This makes perfect sense.
Many visitors also read this article: How Fast Can You Go With Chains on Your Tires?
Are There Any Other Advantages of Higher Rated Tires?
Take into account ride comfort, traction, tire wear, and maneuvering ability. A higher speed rating generally gives better grip and braking control, but it may have a shorter tread lifespan and perform worse in colder weather.
You can raise the speed rating of your vehicle’s tires for better overall performance, but you can’t decrease it without lowering the vehicle’s maximum speed to that of the lower speed rating.
The 8 Reasons Why New Tires Are Often Better Than Repairing
- New tires are always safer than repaired ones
- More pleasing to the eye
- Better traction and handling
- More cost-effective in the long run
- Better reliability
- Less road noise
- Increased fuel economy
- Improved ride comfort
We recommend Priority Tire. They often have clearance sales that result in the cost of a new tire being little more than the cost of repairing the damaged one.
In conclusion
If the load index and speed symbols are greater than the minimal level advised by the vehicle manufacturer, it could also be viable to mix tires with various load index and speed ratings. Install the higher-rated tires on the back axle in these cases.
