While I was searching I found this:


Uniform Tire
Quality Grading

ALL PASSENGER CAR TIRES MUST CONFORM TO
FEDERAL SAFETY REQUIREMENTS IN ADDITION TO THESE GRADES.

TREADWEAR: The treadwear grade is a comparative rating based on the wear rate of the tire when tested undercontrolled conditions on a specified government test course. For example, a tire graded 150 would wear one and a half (1½) times as well on the government course as a tire graded 100. The relative performance of tires depends upon the actual conditions of their use, however, and may depart significantly from the norm due to variations in driving habits, service practices and differences in road characteristics and climate.

TRACTION - AA, A, B AND C: The traction grades from highest to lowest are AA, A, B and C and they represent the tire's ability to stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. A tire marked C may have poor traction performance.

WARNING:
The traction grade assigned to this tire is based on braking
(straight ahead) traction tests and does not include
cornering (turning) traction.

TEMPERATURE - A, B and C: The temperature grades are A (the highest), B and C, representing the tire's resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the material of the tire to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure. The grade C corresponds to a level of performance which all passenger car tires must meet under the Federal Motor Vehicle Safety Standard No.109. Grades A and B represent higher levels of performance on the laboratory test wheel than the minimum required by law.

WARNING:
The temperature grade for this tire is established
for a tire that is properly inflated and not overloaded.
Excessive speed, under inflation, or excessive loading, either separately
or in combination, can cause heat buildup and possible tire failure.

 

Tire Rack?

 

What was the question?

I'm lost.

 

NHTSA is where this Info comes from.

The question was who makes the rating for tires Maufactor or Gov...

 

Who asked that question?

 

It was a conversasion in one of the way too many tire threads on here, Since there are too many to do a search- just trust me it was a question.

And some people had said that the tire companies had the final say on what the rating was.

 

I've been wondering how they rate tires for a long time, good post!

 

isn't that info also printed on the sticker on every new tire? I think I've read it there as well.

 

You did Reid, don't you remember?

 

You should have put better keywords in your title for future searchs

 

Your right, did not even think about that. Opps

 

I am pretty sure that the tire wear rating is ONLY comparable with manufacturers.

i.e. bridgestone tread wear of 200 vs dunlops 200 is not the same rating

it is only consistent within the manufacturer's line of tires