Making a decision about buying tires usually comes down to price and tread wear. Most people are looking for the best of both worlds—a bargain priced, long-lasting tire. Finding low prices is mostly the easy part, but gauging tread wear is a black art. User reviews, word of mouth, previous experiences with a tire brand, and manufacturer claims in the form of treadwear warranties all play into the decision. And there’s also the government’s treadwear ratings.
Treadwear mileage warranties are easy to understand and are almost universal in structure. Basically, the manufacturers pay consumers for a tire’s treadwear shortfall. Likewise, manufacturers assign treadwear grades following strict government protocols. The grades are less intuitive, not based on specific mileage, but a comparison of one tire to another. A tire with a grade of 200, say, is said to wear twice as long as one graded 100. Comparing mileage warranties and government grades should be straightforward, but it’s not. Turns out some manufacturers are more conservative in their claims, and marketing strategies tend to blur direct comparisons between tire companies.
To put the models on the same playing field, we came up with our own comparative tread-life test several years ago. Its reflected in our tread life ratings for most tires, excluding winter tire products. We typically run all-season tires on cars to 16,000 miles—more than double the mileage called for by the government.
Here’s why doing such an expensive, time-consuming test is worth it.
- Our last test of 20 regular all-season tire models had treadwear warranties ranging from 40,000 to 100,000 miles. You might guess that the longest wearing tires were those with 100,000 mile warranties—not so. A pair of these overachieving treadwear warranty tires rated just “average,” the same rating as the 40,000-mile treadwear warranty tire. Ouch. Official treadwear grades were also not foolproof, as the 40,000 mile warranty tire had a so-so 420 grade. The other two had impressive 700-720 grades.
- Some tires do deliver what we expect, achieving an “excellent” tread-life rating as reflected by their impressive 80,000 to 90,000 warranties. But we found similar warranty tires achieving the gambit in our ratings from “fair,” “good,” “very good,” to “excellent” scores. We’re talking about a fairly wide window of mileage projections—from 57,400 to 91,500 miles between two models with the same warranty.
- The government’s treadwear grades were no less challenging. There doesn’t seem to be consistency between treadwear warranties and treadwear grades as assigned by different manufacturers. For example, we tested two models with the same 85,000-mile tread wear warranty, but treadwear grades varied quite a bit from 680 to 800. Our test did indicate that the tire with the 800 score had the better tread life. But it’s no guarantee of better tread life as we found a fairly wide swath of tires graded between 420 to 780 having a similar wear potential in our test.
So, how do you find a long-wearing tire? Well, neither treadwear warranty nor the government’s treadwear grades are a definite guide, but it’s a start. For sure, if a tire has an impressive warranty, it ought to have an impressive treadwear grade. We find warranty and treadwear grades to be a better tool for comparing models within a single manufacturer’s lineup than across different manufacturers. Also, you might find user reviews helpful, but don’t rely on just a few glowing comments because everything is highly dependent on what people drive and various road and weather conditions. Good vehicle maintenance and properly inflated tires can go a long way in getting the most miles out of a set of tires.
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