What makes a good tire? That’s easy. When choosing a tire for your vehicle, consider your needs as a driver including your driving style, distance, types of roads you usually travel, and the weather you typically encounter. Once those are determined, you can easily find the tire that best fits your car, and best fits your needs. There is no one tire fits all, so it’s important to know what all those numbers on your tire’s sidewall mean.
The U.S. Government has developed a tire rating system based on results from tests performed by manufacturers on treadwear, traction, and temperature resistance to identify each tire’s performance capability. The Uniform Tire Quality Grading Standard (UTQG) scale provides ratings for you, so you know the info when trying to buy the right tire. The UTQG system applies to passenger car tires and has their grades stamped on the sidewall. Here’s how it works:
Some people prefer longer tread life when choosing their tire. This test determines precisely that: the mileage your tire will last. Tires with a higher grade represent a better resistance to wear. Grades range from 100 to 600 in 20-point increments. The tests are completed on a 400-mile course under controlled conditions to ensure all tires have the same environmental obstacles. The vehicles must travel a total of 7,200 miles! Talk about a boring road trip!
The treadwear grade provides baseline knowledge for tire manufacturers to market typical wear. Of course, real world driving is slightly different. Weather, driving habits, wheel alignment, and rotation schedule will also play a huge part in understanding one’s own treadwear performance.
The grade for traction is essential since many drivers depend upon having the most reliable tires that provide stability and safety. The UTQG grades measure the ability of the tires to help stop a vehicle driving 40 mph on wet surface, locking the wheels. The traction grades are a letter system designated by mathematical geniuses identifying the best deceleration levels.
Ultimately, whichever tire stops the shortest is the best! This grading system doesn’t take into account hydroplaning, acceleration, or cornering. It simply measures locked wheel friction in emergency stops. The grades are AA, A, B, and C. An AA graded tire should perform better and stop shorter on wet surfaces than those with lower grades.
Not many consider heat as being a prime contributor to tire failure. But underinflated tires heat up faster and on hot pavement may lead to a blowout. So, manufacturers want to know every tire’s ability to resist and dissipate heat. This particular test determines grades by an indoor road wheel under controlled laboratory conditions and includes 30-minute runs in 5 mph increments starting at 75 mph. It increases until the tire reaches the highest speed or eventually fails. Temperature grades for tires are determined based on speeds reached without failing and are: A (over 115 mph), B (100 to 115 mph), and C (85 to 100 mph). Every single tire in the U.S. must meet the minimum grade of C in order to be sold.
It’s easy to overlook, but tires are the only point of contact between you and the road when driving, so tire ratings are crucial to your performance and safety. The technology that goes into developing your tires is just as in-depth as the engineering that’s under the hood. When looking at tire comparisons, keep in mind which tires pass the UTQG tests for an easy tire buying experience!