Tire Speed Rating

[Donald]

My 94 Camry wagon takes a H speed rated tire. The local Sams club will only install a H rated (or better) tire, but they do not carry any in the size I need. Another tire place in NY (Mavis Tire) says the speed rating is purely a speed rating and nothing to do with handling or sidewall strength. I believe they will install a tire with a lower speed rating like a S. So whats the real deal here, is the speed rating pursely speed and thus a S rated tire is fine for my Camry wagon?

 

[uconn1150]

Although you may not utilitze the 'H' rated tire speed, its construction (including sidewalls) is much better than a 'S'. This really comes into play in emergency situations. Also, your car (esp a wagon) will handle differently with a lower rated tire.

Don't skimp on tires...they are the most important safety device!

 

[John K]

IMO, it would be ok if you didn't exceed the speed rating. The tire has a load rating, and if you compare them you should be able to see if there is any difference in load ratings with the speed ratings. I think the higher speed ratings are needed to hold up to the higher heat buildup with higher speeds, might check some online sites, like www.tirerack.com. You could also direct the question to them. Definitely need to check with someone with ddirect knowledge on the issue....

 

[CapriRacer]

Mavis Tire, huh?

Good info, since they don't know what they are talking about.

The truth about speed ratings is that:

1) As a general rule, the higher the speed rating the more responsive the tire to steering input.

2) As a general rule, the higher the speed rating the gippier the tread compound - and what comes along as a result is the more rapid the wear.

3) The higher the speed rating, the less likely the tire will fail. (You are using less of its capability)

For these reasons, many tire shops will not install lower speed tires, but it's the last reason that has forced tire shops to re-evaluate how strongly they adhere to the rule (at the risk of losing a sale.)

A lawsuit can be very expensive
Hope this helps.

 

[labman]

Speed ratings are over done. I doubt my 02 Cavalier with the Ecotec and 5 speed can get up to 130 mph the H rated tires it came with are good for. I don't think I would want an M. I cruise entirely too close its 81 mph rating. Tire stores forcing me to purchase tires good 130 mph when my car can't go that fast makes as much sense as H being between U and V. Maybe I could make do with a P or a Q and have a cheaper tire, quiet, soft riding, long wearing, and hold the road good in the wet. My wife is going to scream long before I reach it cornering limits.

 

[mechtech]

The speed ratings are to certify that the tire will hold up to the stated speed for 20 minutes, without failure.
To me, better construction and materials is worth a little extra price.
If you have a vehicle that only sees local trips at low speeds, you can get cheaper tires with no downside.

 

[Donald]

Oddly the current tires on the Camry to not seem to have a speed rating that I can see (OK...old eyes). I would guess my Dad had these tires installed maybe 5-6 years ago.

So if the H tires are worth the extra $$, why would not everyone get H tires and forget the S rated tires. If Sams Club has only S rated tires in this size, that says the bulk of cars out there needing this size tire take an S. Why is Camry different?

 

[Donald]

Looked on TireRack for this vehicle and they do not push using H rated tires. They basically say that H rated tires are for Sports Sedans and Coupes. This is a Camry Wagon.

 

[ATS-V]

Also keep in mind that tires that grip better stop better. I always use H rated tires, I would go "V" or higher but I use my car year round and have to deal with snow on occasions.

BTW: I have talked to Mavis before, they were not knowledgable. Where abouts in NY?

 

[uconn1150]

quote:

---

Originally posted by Donald:
Oddly the current tires on the Camry to not seem to have a speed rating that I can see (OK...old eyes). I would guess my Dad had these tires installed maybe 5-6 years ago.

So if the H tires are worth the extra $$, why would not everyone get H tires and forget the S rated tires. If Sams Club has only S rated tires in this size, that says the bulk of cars out there needing this size tire take an S. Why is Camry different?

---

LOL, look where you are at. Here we $$$ a bit more for better oil, we could all be using Wal-Mart ST, but instead some of us want the best! It's just personal choice. 3k OCI with ST is fine for most people, just like the 'S' tires. But for us "in the know" a few extra bucks for better performance is a no-brainer.

 

[Gary Allan]

Yes, Winston. I learned about these back in 1974 in auto skewl.. They've added a couple since then.

web page


Speed Rating

In Europe, where selected highways do not have speed limits and high speed driving is permitted, speed ratings were established to match the speed capability of tires with the top speed capability of the vehicles to which they are applied. Speed ratings are established in kilometers per hour and subsequently converted to miles per hour (which explains why speed ratings appear established at "unusual" mile per hour increments). Despite the tire manufacturer's ability to manufacturer tires capable of high speeds, none of them recommend the use of their products in excess of legal speed limits.

Speed ratings are based on laboratory tests where the tire is pressed against a large diameter metal drum to reflect its appropriate load, and run at ever increasing speeds (in 6.2 mph steps in 10 minute increments) until the tire's required speed has been met.

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.

Over the years, tire speed rating symbols have been marked on tires in any of three ways shown in the following examples:
225/50SR16 225/50SR16 89S or 225/50R16 89S

Each of these was an acceptable method of identifying speed ratings.

Early tires had their speed rating symbol shown "within" the tire size, such as 225/50SR16. Tires using this type of branding were not to have been produced after 1991.
225/50SR16 112 mph, 180 km/h
225/50HR16 130, 210 km/h
225/50VR16 in excess of 130 mph, 210 km/h

Beginning in 1991, the speed symbol denoting a fixed maximum speed capability of new tires must be shown only in the speed rating portion of the tire's service description, such as 225/50R16 89S. The most common tire speed rating symbols, maximum speeds and typical applications are shown below:
M 81 mph 130 km/h
N 87 mph 140km/h Temporary Spare Tires
P 93 mph 150 km/h
Q 99 mph 160 km/h Studless & Studdable Winter Tires
R 106 mph 170 km/h H.D. Light Truck Tires
S 112 mph 180 km/h Family Sedans & Vans
T 118 mph 190 km/h Family Sedans & Vans
U 124 mph 200 km/h
H 130 mph 210 km/h Sport Sedans & Coupes
V 149 mph 240 km/h Sport Sedans, Coupes & Sports Cars

When Z-speed rated tires were first introduced, they were thought to reflect the highest tire speed rating that would ever be required, in excess of 240 km/h or 149 mph. While Z-speed rated tires are capable of speeds in excess of 149 mph, how far above 149 mph was not identified. That ultimately caused the automotive industry to add W- and Y-speed ratings to identify the tires that meet the needs of new vehicles that have extremely high top-speed capabilities.
W 168 mph 270 km/h Exotic Sports Cars
Y 186 mph 300 km/h Exotic Sports Cars

While a Z-speed rating still often appears in the tire size designation of these tires, such as 225/50ZR16 91W, the Z in the size signifies a maximum speed capability in excess of 149 mph, 240 km/h; the W in the service description indicates the tire's 168 mph, 270 km/h maximum speed.
225/50ZR16 in excess of 149 mph, 240 km/h
205/45ZR17 88W 168 mph, 270 km/h
285/35ZR19 99Y 186 mph, 300 km/h

Most recently, when the Y-speed rating indicated in a service description is enclosed in parentheses, such as 285/35ZR19 (99Y), the top speed of the tire has been tested in excess of 186 mph, 300 km/h indicated by the service description as shown below:
285/35ZR19 99Y 186 mph, 300 km/h
285/35ZR19 (99Y) in excess of 186 mph, 300 km/h

As vehicles have increased their top speeds into Autobahn-only ranges, the tire speed ratings have evolved to better identify the tires capability, allowing drivers to match the speed of their tires with the top speed of their vehicle.

 

[labman]

I still think it is insane to fuss about whether my car needs a tire that can go faster than it can. Putting an H, rated for 130 mph ona Cavalier is pure bling bling.

 

[Winston]

I believe the whole speed rated thing started in Europe. The required speed rating for a tire was based on the cars top speed. Thus, a BMW would require a higher speed rating than Ford Escort. Of course, it is not uncommon for people to drive their cars at top speed on some roads in Europe.

Now in the US, how often do you drive your car at top speed? I think even an S rated tire is rated for speeds up to around 95 mph. The only critical issue with speed rated tires is their resistance to failure at high speed. The whole issue about handling, etc is **. Every different brand of tire will handle differently. There are trade offs with every tire choice. The difference in handling/performance due to speed rating is insignificant compared to the brand/model of tire effect on handling.