Originally Posted By: JMJNet
Originally Posted By: mightymousetech
Comparing tread wear ratings between manufacturers is meaningless.
This is true.
Because the treadwear rating is just a comparison relative to tires made in the same brand.
The tire used as a reference point on different brand may not be exactly the same.
So different brand of tires will have different starting reference point.
Sorry, guys!
The treadwear rating is based on a comparison to the SRTT (Standard Reference Test Tire - and if I remember correctly, made by Michelin in a Uniroyal brand.) These tires are carefully made, carefully stored, and carefully monitored for consistency. Did I mention they are expensive and difficult to obtain by the average joe? They have to be requested from Michelin directly.
And while there are some interesting aspects to the rating, they can be compared between brands - that's the whole purpose of the rating.
So here are some interesting things about the UTQG treadwear rating:
It is based on a test run in Texas. There are at least 2 vehicles involved (one for the SRTT, the other for the target tire) - and because of the cost involved, usually a lot more. There is a prescribed route and must be basically dry when it is run. The route is over regular roads. It's about 10,000 miles in duration and the treadwear is extrapolated. (and, Yes, the test is expensive to run, which is why many of the tests are for quite a few different tires at the same time.)
The Feds can request the data used to determine the rating. (And I have been involved in one such inquiry.)
The test is not very precise and there is quite a bit of variation. For that reason, I use a 10% value for significance. In this case the difference is over 10%, so those tires are different.
But in the real world, actual tread life varies quite a bit - although, more or less along the lines of the UTQG ratings. But I have seen reversals of treadwear data based on differences in the paving material.
