Speed Rating debate..and Tire Rack

[flinter]

Hi,

There seems to be a lot of confusion about tire speeding rating
on this forum.

I called Tire Rack yesterday and was fortunate to actually
speak to one of the top track testers at their Indiania facility
and test track.

Several area tire shops in my area have told me DO NOT ever
drop a speed ratings when replacing tires.

Tire Rack tells me this is totally untrue. Hes says although
this may have agreed with that in 1988, the tolerances of today's
tire speed ratings is so tight that unless you are on a racetrack, you will NOT notice any difference in dropping
from a H Rated to a T Rated for the average to conservative
driver.

I own a 2006 Hyundai Elantra GLS sedan and am looking to
replace my worn Michelin H rated tires with the Continental
ProContact EcoPus tire. This tire actually won 1st place in
Tire Rack's test of 4 Low Rolling Resistance tires, with
the best for handling and wet traction.

Tire Rack tells me they have a contact with Hyundai and
Hyundai HAS approved Tire Rack to sell H or even S Rated
tires on my Elantra.

Yet still, some shops will not recommend T Rated tires for
my Elantra!

 

[eljefino]

 

[Quattro Pete]

Anything with an H-rating and above is generally a better made tire...

http://www.barrystiretech.com/speedratings.html

 

[CarbonSteel]

Originally Posted By: flinter
Tire Rack tells me they have a contact with Hyundai and Hyundai HAS approved Tire Rack to sell H or even S Rated tires on my Elantra.

Two questions--have you seen the contract and what does Hyundai say? Obviously, one could install any tire one desires on the car, but what is safe to install? Driving habits and conditions play a role here, but (at least for me) for what little bit of money that could be saved, I would not take any risks--but that is me...YMMV.

 

[flinter]

Risks?? I am a very conservative driver in the suburbs and drive
around 10,000 miles a year. Dropping from a H to a T Rated for
a 2005 Hyundai Elantra seems to be a non issue.

I have no reason not to believe that Tire Rack has a contact
with Hyundai, why would the man lie about that?

Besides, dont you think that if Hyundai did NOT approve, Tire
Rack would be getting tons of lawsuits by now for selling T
and S rated tires to 1000's of Elantra/Sonata owners?

 

[Burt]

I'll say that I am confused. I thought speed rating was an indication of the maximum speed that they are designed to run at. Higher speed tires tend to use softer rubber compound and grip better and wear out faster. Are there any other generalizations that you can make?

I also thought the tire sellers don't like to sell you lesser rated tires for liability reasons. Basically they don't want to put tires rated for 110 mph on a car that has enough hp to go 130 mph even if you claim you will never go that fast.

 

[Quattro Pete]

Originally Posted By: Burt
I'll say that I am confused. I thought speed rating was an indication of the maximum speed that they are designed to run at. Higher speed tires tend to use softer rubber compound and grip better and wear out faster. Are there any other generalizations that you can make?

Quote from CapriRacer's article I linked to above:
Quote:
To get a tire to pass an H speed rating almost requires the tire to have an overlay - commonly called a "cap ply" and nylon is a commonly used material.

This overlay restricts the growth of the tire due to centrifugal forces as well as the movement caused by the standing wave. Not only does this result in reduced stresses in the tire, it also reduces heat generation.

 

[CapriRacer]

Originally Posted By: flinter
Hi, There seems to be a lot of confusion about tire speeding rating on this forum.......

And elsewhere as well

Originally Posted By: flinter
......I called Tire Rack yesterday and was fortunate to actually speak to one of the top track testers at their Indiania facility and test track.

Several area tire shops in my area have told me DO NOT ever
drop a speed ratings when replacing tires.

Tire Rack tells me this is totally untrue. Hes says although
this may have agreed with that in 1988, the tolerances of today's
tire speed ratings is so tight that unless you are on a racetrack, you will NOT notice any difference in dropping
from a H Rated to a T Rated for the average to conservative
driver........

I am hoping that you have paraphrased that wrong, because usually the folks at Tire Rack generally avoid making blanket statements like that - especially when there is an obvious un-truth contained within the statement.

First, as a general rule, the higher the speed rating, the more responsive the handling - and by handling I mean how quickly the tire (and therefore the vehicle) reacts to steering input. This is not grip, but how the thing "feels".

The problem here is that there are quite a few tires that are exceptions to this rule.

Just an FYI, handling (see my meaning above) and ride quality (meaning softness, plushness, etc, not smoothness, or vibration-free) are in opposition.

I just can not imagine that a guy a Tire Rack would make a statement like that - and if he did, he would be wrong. That's why I suspect, he may have said something that might resemble that - like: "The difference between a T rated Goodstone FireEagle ST, and an H rated version of the same tire is such the average person wouldn't notice the difference." THAT sort of statement is probably true for many tire lines, but it is not necessarily true when different lines of tires are compared.

Originally Posted By: flinter
.......I own a 2006 Hyundai Elantra GLS sedan and am looking to
replace my worn Michelin H rated tires with the Continental
ProContact EcoPus tire. This tire actually won 1st place in
Tire Rack's test of 4 Low Rolling Resistance tires, with
the best for handling and wet traction.........

And this MIGHT be where the confusion lies - The guy at Tire Rack was trying to do a comparison between the Michelin and the Continentals - and that might make sense.

Originally Posted By: flinter
.......Tire Rack tells me they have a contact with Hyundai and
Hyundai HAS approved Tire Rack to sell H or even S Rated
tires on my Elantra.......

No, they don't! No vehicle manufacturer is going to do a carte blanche like that. I work for a major tire manufacturer and as big a retailer as Tire Rack is, our company would never be able to get that sort of waiver from ANY vehicle manufacturer - we have considerably more pull than Tire Rack does. Further, we sit on industry committees that publish guidelines about tire replacement - and if there was some agreement from some vehicle manufacturer that you can do this type of substitution, the word would quickly spread.

Nope! I don't believe this at all!

Originally Posted By: flinter
.......Yet still, some shops will not recommend T Rated tires for my Elantra!

And for good reason: Let's say there is a vehicle accident where the driver might have been able to avoid hitting something - but didn't. Any sharp attorney would jump right on the H vs T speed rating thing and argue that the accident could have been avoided - and it's the tire shop's fault. No tire shop wants to accept this kind of legal liability.. However, some shops don't see this as a huge risk - and some do!

I'm NOT an attorney, but my understanding of the law is that even if there is a waiver signed by the vehicle owner, the tire shop - who is in theory more knowledgeable - is still liable.

Sorry, but I thoroughly disagree.

 

[flinter]

The Tire Rack tester I spoke was indeed camparing the OEM Michelin
Energy MXV4 plus to the new Continental Eco Plus line of tires,
which are T rated.
He tells me for the average everyday driver, I will feel NOT feel a differnce in handling. In fact, he tells me I will feel an
improvement with this model Conti, with MUCH better wet traction
and a MUCH more comfortable, smoother pleasant ride.

As I stated, I am a conservative driver, and NEVER push my Elantra
even over 75MPH.

 

[Eddie]

i HAVE READ THAT IT IS ILLEGAL IN MANY STATES FOR A TIRE SHOP TO INSTALL TIRES THAT ARE SPEED RATED LOWER THAN IS SUPPLIED FROM THE FACTORY. ops sorry about the caps but, too tired to retype. I see no value in lowering the speed rating which is NOT only a speed rating but, has to do with handling also. JMO.. Ed

 

[Boomer]

CapriRacer, you are spot on fro a legal position. The other day, I made a similar comment to someone on this board about disabling their anti-lock brakes. I spent a lot of time over the years participating in depositions as a scientist when my employer was sued or was suing someone else. These are not pleasant experiences. They are lengthy and quite detailed and you have to answer everything truthfully or else you are guilty of perjury. Lawyers are all well aware of all the things to look for and in a car accident, I am sure they have a checklist of things such as tires, brakes, failure to do required inspections, etc.

So if your car or truck has a certain type of tire, try to stick with it. For example, people put LT tires on light trucks that came with P rated tires and then run them at the same pressure which can cause a blowout eventually. A quick search on the Internet reveals this. If I or you can find, so can an attorney and his/her staff.

 

[Doog]

I dropped from H to T on my Toyota SUV with some Michelin tires. Just make sure you have the same load rating. T will be good up to 118 mph so keep it under 110mph and you are good.

Keep them inflated properly...no problem. I have driven mine on 3000 mile highway trips. No issues.

A tire shop refused to install them but my dealer approved it.

 

[flinter]

Eddie,

If its illegal, that why on earth does Tire Rack list and link
many of their preferred and highly rated installers in NJ as
aceepting their tires that are T rated for car's that have H
rated as OEM??

 

[Doog]

Originally Posted By: flinter
The Tire Rack tester I spoke was indeed camparing the OEM Michelin
Energy MXV4 plus to the new Continental Eco Plus line of tires,
which are T rated.
He tells me for the average everyday driver, I will feel NOT feel a differnce in handling. In fact, he tells me I will feel an
improvement with this model Conti, with MUCH better wet traction
and a MUCH more comfortable, smoother pleasant ride.

As I stated, I am a conservative driver, and NEVER push my Elantra
even over 75MPH.


You will never know the difference as long as the load rating is the same.

 

[Food Scientist]

This is why you go ahead and just do it instead of asking the entire world for their opinion. If it doesn't work then you learn the hard way.

Taking the wheels in loose will also get around tire shops not installing the tire because they don't know what vehicle they go with.

 

[FowVay]

Here's a example: I mount snow tires on my Jetta. My Jetta has 91H rated all-season from the factory. My snow tires are 91T rated for winter use.

This is a very common situation. It is so common that the German car makers even give you the option of setting a speed minder on your multi-function display to warn you when you've reached the speed rating of your tires.

When I run all-season 91H tires on my Jetta I turn the speed minder off completely. When I mount snow tires I set my speed minder to 85 MPH. It will sound a "DING" through the stereo speakers and a message will flash on my dash that I've exceeded my pre-set speed rating if/when I reach 85MPH.

I ALWAYS replace my all-season tires with identical load and speed rated replacement tires. It only makes sense.

 

[Chris142]

I went through something like this a few years ago. I ruined a tire on a Sunday and the only place open was Big-O. I wanted to upgrade to a more agressive off road tire.

This was on my Jeep Wrangler. This Jeep is happy @ 62mph. Speed limit in Ca is 70mph. I have a class A license so I can't go to traffic school if I get a ticket and I get a double fine too.

Needles to say I don't go over 70mph.

Big-O wouldn't sell me a more agressive set of off road tires and they kept bringing up the 130+mph tire ratings. 130 mph in a Wrangler? Me? No way!

I ended up with a set of street oriented tires that rode terrible and followed every crack in the road. But they were high speed rated!

I ran those as long as I could stand and eventully replaced them with the agressive off road tires I originally wanted. They (the speed rated tires)still had 80% of their tread when I replaced them but the handling was awful.

I could see a Corvette or Porsche needing high speed tires. Not my Wrangler with 3.73 gears in the axles and a 6-cyl though.

 

[CapriRacer]

Originally Posted By: Doog
You will never know the difference as long as the load rating is the same.


This is TOTALLY false!

And this is why I visit a dozen or so websites every day.

The truth is that there are combinations of things where you won't notice the difference, but there ARE combinations where you will!

 

[flinter]

The OEM Michelin Energy MXV4 plus and the Continental ProContact
EcoPlus are the same load ratings, but the Michelin is H Rated
and the Conti is T Rated.

 

[IndyIan]

Originally Posted By: CapriRacer
And for good reason: Let's say there is a vehicle accident where the driver might have been able to avoid hitting something - but didn't. Any sharp attorney would jump right on the H vs T speed rating thing and argue that the accident could have been avoided - and it's the tire shop's fault. No tire shop wants to accept this kind of legal liability.. However, some shops don't see this as a huge risk - and some do!

Really? Do cops actually make notes on tire speed ratings at an accident scene, and then look at the door sticker for that trim level of the car? I'm sure they look to see if a tire is on the wear bars, or has "odd" tires, but that's about it. I'd think if you have "normal" and "reasonable" tires in "normal condition" how can anyone say the speed rating would make any difference in "normal driving conditions".
3% difference on a lap on a track translates to no siginificant difference in a single accident avoidence maneuver.
I know you are an expert in this field and can't recommend anything other than going "by the book", but if the OP drives "normally" as a lay person, I think there will be no significant differences by going down a speed rating. If the OP has a teenager who borrows the car, and may test the limits, then sure get the speed rated tire that the car came with.