Despite advances in longer-lasting tires, actual tread life will vary by car type, tire type (such as all season or high performance), driving aggressiveness, and even road and weather conditions. Car owners still need to replace their tires a few times or more throughout the life of a typical vehicle. As the adage goes, nothing lasts forever.
Proper maintenance and responsible driving can maximize the mileage in a set of tires. Monthly tread inspections can inform when the tires warrant replacement, well in advance of the federally mandated tread-wear indicators. In most states, tires are legally worn out when their tread depth reaches 1/16 inch (or 2/32 inch as found on standardized tread-depth gauges). The easiest way to measure this, if you don't have a gauge, is to hold a penny upside down in the tread. If the top of Lincoln's head is visible, you need new tires. But using a penny standard doesn't work for all weather conditions. We have found in our tests that a tire with just 1/8-inch tread was notably worse in hydroplaning resistance and snow traction. By the time only 1/16 inch remains, wet-pavement cornering and braking drop off too. Based on our experience, when your tires have less than 1/8 inch of tread left, it's a good time to start shopping for replacement tires.
As a better indicator of tread wear, place a quarter upside down in a tire groove. The distance from the coin's rim to George Washington's hairline is about 1/8 inch. If you see all of his head in any one groove where a tread-wear indicator appears, consider shopping for new tires.
Once a need for new tires is determined, it is necessary to identify the best tires for your vehicle and driving demands.
How to choose
Put safety first Look for tires that do well in our tests for braking, handling, and resistance to hydroplaning. Winter traction should also be considered, if applicable. Let tread wear, ride comfort, noise, and rolling resistance be tiebreakers. Our comparative tread-life tests demonstrate that a manufacturer's warranty doesn't always reflect how a tire will wear.
Read the fine print
The tread-wear warranties manufacturers provide for their tires are pro-rated; the more miles on the tire, the less credit you get on a replacement. And most tire warranties only cover damage resulting from regular use and don't cover damage resulting from potholes or other road hazards.
Tire prices can vary widely by region, and retailer. Check independent tire dealers, online or mail-order stores, tire chains, car dealerships, department stores, and warehouse clubs. Be sure to ask whether the price includes mounting, balancing, and new valves, which can increase the total cost.
Look at the sidewall of a tire for a designation beginning with DOT (for Department of Transportation). The last four digits of the designation indicate the week and year of manufacture. For example, 3307 means the tire was made during the 33rd week of 2007. Don't purchase tires that are more than a few years old.
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