^^

 

They're specific to each manufacturer, and based on a standard tire each manufacturer uses. They have a 100-treadwear standard and base their other tires off of that. So a 200-treadwear goodyear may not have the same life as a 200-treadware michelin.

RJ

 

A ouija board, a sheep's head, and Sandy Bullock.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">They're specific to each manufacturer, and based on a standard tire each manufacturer uses. They have a 100-treadwear standard and base their other tires off of that. So a 200-treadwear goodyear may not have the same life as a 200-treadware michelin.</TD></TR></TABLE>

Stolen from another board ( here ):

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">I've heard that said before many times, but I don't know where it comes from. My understanding of the UTQG treadwear rating system is that it is compared to a "standard" reference tire in controlled government specified testing conditions. UTQG stands for Uniform Tire Quality Grade. It should not vary by manufacturer since all tires are tested exactly the same way. It will vary by driving conditions since it's a relative measurement. e.g., if you got 10,000 miles out of a tire with a 100 rating you would get 20,000 miles out of one with a 200 rating, but your buddy might only get 10,000 miles with a 200 rating because he drives more aggressively or on different surfaces, etc.

http://www.nhtsa.dot.gov/cars/testing/UTQG/
</TD></TR></TABLE>
A few more links:
http://www.tiretesting.com/1g-utqg.htm
http://www.goodyeartires.com/k....html

Goodyear's site is quite contradictory...

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">The tread wear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test track. A tire graded 200 would wear twice as long on the government test track as one graded 100. ...they are not valid for comparisons between manufacturers. </TD></TR></TABLE>

Uh. Right. So although a 200 treadwear tire wears twice as long as the government tire rated at 100, twice as long in a controlled environment might be different depending on manufacturer? I don't know who to believe anymore.

 

UTQG ratings are determined by running a sample tire through a specific test route/conditions. All tire manufacturers use basically the same testing, because it is a govenment regulated test. The catch is that you don't usually put the highest rating on the tire that you could, because it's important for a manufacturer's tire lines to make sense and for the UTQG ratings between various tire lines to be consistant with their place in the market. In other words, I usually know what UTQG rating I want to give a tire before I test it. The test confirms that I can use that rating, but if I was shooting for a 400 and the test came back and said it rates 670, I'm not necessarily going to put the higher number on the tire, for several reasons. First, that higher rating might be higher than a more expensive tire we sell, and second, some people view those numbers in an inverted way, and assume that the higher rated tires must be harder and thus won't handle as well.

A tire rated 100 provides equal mileage to a control tire that is produced by one manufacturer and provided to all others for testing. Since most tires actually test much higher than they are rated, it is difficult to compare ratings between manufacturers with a high degree of accuracy. If the difference is 200, then there's going to be a difference, but much less than that and it's not going to be all that usefull. Mileage warranties are a MUCH BETTER indicator of mileage, because we have to pay if the tire doesn't last as long as the warranty said it would.

-Chris (Yes, I do work in the tire industry, as a tire designer)

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by stealthx32 &raquo;</TD></TR><TR><TD CLASS="quote">

Stolen from another board ( here ):

</TD></TR></TABLE>

The other board is wrong. You think Goodyear has it wrong? I would believe them to be most accurate. Also check the TireRack.

http://www.tirerack.com/tires/...g.htm

Simply, each company chooses their UTQG tire and calls that UTQG 100. Then, using government test specifications (i.e. test surface, duration, conditions, etc), compare all their other tires to the 100 UTQG tire.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Shmeek &raquo;</TD></TR><TR><TD CLASS="quote">Simply, each company chooses their UTQG tire and calls that UTQG 100. Then, using government test specifications (i.e. test surface, duration, conditions, etc), compare all their other tires to the 100 UTQG tire.
</TD></TR></TABLE>

Doesn't that remove the "uniform" aspect of the UTQG rating? I think I buy into Chris's theory more.