360 Treadwear

[ampao]

I've been looking at edgeracing.com for some new tires. And being a noob, I dont know what treadwear 360 means. Is it really only good for 360 miles!? or does that mean 360k?

Thanks!

[nighthawk]

Treadwear Grades

UTQG Treadwear Grades are based on actual road use in which the test tire is run in a vehicle convoy along with standardized Course Monitoring Tires. The vehicle repeatedly runs a prescribed 400-mile test loop in West Texas for a total of 7,200 miles. The vehicle can have its alignment set, air pressure checked and tires rotated every 800 miles. The test tire's and the Monitoring Tire's wear are measured during and at the conclusion of the test. The tire manufacturers then assign a Treadwear Grade based on the observed wear rates. The Course Monitoring Tire is assigned a grade and the test tire receives a grade indicating its relative treadwear. A grade of 100 would indicate that the tire tread would last as long as the test tire, 200 would indicate the tread would last twice as long, 300 would indicate three times as long, etc.

The problem with UTQG Treadwear Grades is that they are open to some interpretation on the part of the tire manufacturer because they are assigned after the tire has only experienced a little treadwear as it runs the 7,200 miles. This means that the tire manufacturers need to extrapolate their raw wear data when they are assigning Treadwear Grades, and that their grades can to some extent reflect how conservative or optimistic their marketing department is. Typically, comparing the Treadwear Grades of tire lines within a single brand is somewhat helpful, while attempting to compare the grades between different brands is not as helpful.

[ampao]

Treadwear Grades

UTQG Treadwear Grades are based on actual road use in which the test tire is run in a vehicle convoy along with standardized Course Monitoring Tires. The vehicle repeatedly runs a prescribed 400-mile test loop in West Texas for a total of 7,200 miles. The vehicle can have its alignment set, air pressure checked and tires rotated every 800 miles. The test tire's and the Monitoring Tire's wear are measured during and at the conclusion of the test. The tire manufacturers then assign a Treadwear Grade based on the observed wear rates. The Course Monitoring Tire is assigned a grade and the test tire receives a grade indicating its relative treadwear. A grade of 100 would indicate that the tire tread would last as long as the test tire, 200 would indicate the tread would last twice as long, 300 would indicate three times as long, etc.

The problem with UTQG Treadwear Grades is that they are open to some interpretation on the part of the tire manufacturer because they are assigned after the tire has only experienced a little treadwear as it runs the 7,200 miles. This means that the tire manufacturers need to extrapolate their raw wear data when they are assigning Treadwear Grades, and that their grades can to some extent reflect how conservative or optimistic their marketing department is. Typically, comparing the Treadwear Grades of tire lines within a single brand is somewhat helpful, while attempting to compare the grades between different brands is not as helpful.

So the 360 Treadwear grade means 7,200 * 3.6? i.e. Almost 26k miles?

[benji]

So the 360 Treadwear grade means 7,200 * 3.6? i.e. Almost 26k miles?

Theoretically, yes. IMO, it isn't worth trying to figure out how long your tires will last using just treadwear rating. Instead, think of it more as a 300 will wear out faster than a 400, that kinda thing. As the post above says, it doesn't help when comparing between different manufacturers.

A better guide might be to look at the mileage warranty offered, or to look at the tire on tirerack.com and read the reviews (what I do). People will tell you about how they are wearing for them, and there are always a few people that have an Accord.

There is also a thread on here where people evaluated tires they had on their cars, but I can't remember where it is for sure. If you search you will find it.

[deevergote]

I was told by a guy at a tire shop that the treadwear numbers vary from manufacturer to manufacturer... that they aren't very consistently rated, and shouldn't be trusted completely.

[evil_demon_01]

I was told by a guy at a tire shop that the treadwear numbers vary from manufacturer to manufacturer... that they aren't very consistently rated, and shouldn't be trusted completely.

Very true - One brand tyre with a rating of 200, can be completely different to another brand with 200 rating.
As there is no set "standard" for the ratings, They are more there to compare between that particular brands product range.

[mayberry]

I was told by a guy at a tire shop that the treadwear numbers vary from manufacturer to manufacturer... that they aren't very consistently rated, and shouldn't be trusted completely.

kinda like alchohol proofs on bottles of booze. how can something be 110 proof. nah mean?

[starchland]

do you actually think a company would sell a tire that only lasts 360 miles and still be in business?

[evil_demon_01]

They'd be rich, Full race tyres are dont last long at all

[ampao]

do you actually think a company would sell a tire that only lasts 360 miles and still be in business?

uhh honestly, I did. hehe embarassed.. maybe they were racing tires or something.