Tire Treadwear Ratings

SON240sx Automotive
1

So, am I the only one who didn’t know that the treadwear ratings on tires are based on absolutely nothing?

I was just doing some random bored-at-work type reading and just realized that the treadwear ratings on tires are only consistant WITHIN a specific tire manufacturer.

To clarify, a tire rated at 200 treadwear by Yokohama might have an equal life to a tire rated at 400 treadwear from a Toyo under the same driving circumstances.

The reason is that the treadwear is tested BY THE MANUFACTURER using their own testing methods, nothing is goverened other than the fact that it must be rated and all tests must be done the same in order to maintain an accurate measurement within that manufacturers tire lineup.

Was I alone in not realizing this?

2

The Traction rating is kind of a funny one too, but I already knew this (I have a feeling a lot of people don’t know this however).

The “Traction” rating on the side of your tire is also sort of misleading - it is based on the STOPPING ability on WET pavement. Hardly a good test for what the group of us need in general from a tire.

3

I found a page that summarizes both of my above posts nicely:

http://www.discounttire.com/dtcs/infoTreadwear.dos

4

You are correct. Its a marketing ploy with some marginal truth to it.

5

Geezus, this is bullshit! :smiley:

Peter, this might be a long shot but what are the chances that YOU were the guy testing the Redline Power Pack in a Miata on Sasha’s Dyno Day a few weeks back?

I saw a photo of you in Modified today on top of one of your columns or something and recognized the face. Maybe you just look a lot like the guy that was there? :smiley:

6

Indeed that was us. Make no mistake though, no of us drive a Miata :slight_smile:

7

Too bad, the mazdaspeed Miata is a nice car.

John, yeah, i knew things weren’t consistent between companies and the traction rating can come in wet and dry. So AA/AA is AA for wet/dry…???

Also, I try to get online reviews of tires however I find this to be a chore in itself.

8

i worked in a tire shop for 2 years and i did not know this!! not that it really matters to much to me. i pick my tires by the tread pattern. the more aggressive the pattern the better the tire. i look for good water venting on the sides. i have gotten tires before that would hydro at 80 on a rainy road(Goodyear’s), swapped them out next summer for a better more spaced out, and deeper tread(Firestone’s) and i couldn’t get it to hydro at 110 on a really rainy day, it had no problem dealing with the rain.

when your at a meet or something ask around and find out what tire most ppl run and what tire they liked the best. pick the one that is most commonly liked and try it out. the only really way you will know is try’n them yourself.

9

Well, yes it is pretty much up to the tire manufacturer, but the other thing we often ignore is driving style and proper inflation.

My dad drives like you’d expect a responsible 60 year old to. He’s really easy on the brakes and acceleration. On my recommendation he runs dedicated summer and winter tires. He’s on UHP summers and he’s on his … 2nd summer now, S03s. That’s about 30,000km and he’s starting to think he should replace them at the start of next summer.

I killed the same set of tires on a car in 2/3 of one summer, maybe 7,000 km. That wasn’t doing burnouts, or massive camber problems. I didn’t like the car and was very hard on it. It also outweighed my dad’s car by 600 lbs at least, made 200 more lb-ft of torque and I ran at much higher average speeds, cornered harder, etc.

So how should Bridgestone rate their tires? The only way they can. They know that for both my dad and I, a harder compound tire would last longer as compared to the S03. I may get 9,000 km and my dad 50,000.

Tire companies have to be arbitrary. If they made it a real standard, people would force businesses to adhere to their ‘promises’ of a tire that will get X miles, regardless. Considering something like 65% of people on the road have improperly inflated tires, it would be almost impossible to have consistency. I saw a lady last week at the gas station putting about 60+ psi into her tires. When I asked her why, she flatly stated that if the tires deform under the weight of the car, they are underinflated and dangerous. They shouldn’t show any signs of bearing load.

This is why I don’t buy into online reviews. Some guy with a Honda Fit will go on and on about how race-bred his tires are, how he corners on rails, no problem in the rain, etc. Then underneath the next review is from a guy with an STi who says they’re terrible. And the guy with the M3 says they’re so-so for the price.

Then there’s stuff like tire tests. Some companies don’t want their tires tested at all. Other companies set up entire events just to promote how good their tires are. The sad thing is you can’t even look at racing too closely. Even the most amateur series will have a ‘spec’ tire. Because a sponsor paid heavily for that privelege. You have to run their tire. They’ll even give you a discount, but if you don’t run their tires, you don’t run.

Hell they can’t even get two identical cars to get identical fuel economy in testing. UTQG is better used as a gradient. If a tire is rated much higher, you know it’s a harder compound, and will last - at the sacrifice of grip.