These tires feature snow traction that almost comparable to that of pure winter tires while offering similar performance in other areas as conventional all-season tires.
They are designated by a snowflake-within-a-mountain symbol on the tire's sidewall. This term is a misnomer, as this type of tire should rightly be called "three-season" rubber.
Summer tires are designed specifically to deliver dry- and wet-weather traction in moderate or warm weather. They sharpen steering response, increase cornering traction by an order of magnitude, and stop your vehicle in much less distance.
But they do so at a cost: most summer tires only work well at temperatures of about 40 degrees Fahrenheit and above.
As outside temps fall toward freezing, the tires can feel skittish and behave inconsistently; they lose a large portion of their grip to the point that they act like they are on a wet or even icy road. More than one driver of a powerful car, unaware of the temperature sensitivity of its summer tires, has lost control and crashed on a cold day.
As with all-season tires, summer rubber comes in several varieties. Tire Rack divides these tires into three main groups by escalating capability: ultra-high performance on the bottom rung, followed max performance and extreme performance. Called "snow tires" in the past, winter tires are designed to provide maximum traction in snow and in slippery winter conditions—and the traction they provide in those situations is not matched by any other category of tire.
Even an all-wheel-drive vehicle on all-season tires cannot match the stopping or turning capability of a similar two-wheel drive vehicle fitted with four winter tires, a point we have proven in our own winter-tire testing.
Winter tires are designed to work well in the cold-weather months, but they don't handle or wear as well as all-season or summer tires once the weather warms up. They should be considered as a second set of tires for your vehicle if you live where snow flies annually. We fit all of our long-term test vehicles with winter tires and they've proven their worth many times over.
Why use winter tires? If you live in the northern states, we recommend purchasing a set of winter tires.
Their deep treads are engineered to deliver a significant traction improvement, and do they ever work. You'll feel safer and be safer, not to mention more relaxed when driving in snow. Retailers such as Tire Rack will sell you a set of snows mounted on steel wheels that you can swap on when winter rolls around.
Here at Car and Driver , we swear by them. Most consumers choose to replace the worn tires on their vehicle with something equivalent in size and capability. This makes a lot of sense; your car was engineered to work well on the type and size of tires it came on, so fitting an identical or similar replacement set would maintain the performance and safety your vehicle was designed to deliver.
We'll get to upgrading later on. To inform your decision process, you'll need to know your vehicle's tire size and speed rating, and you'll also want to consider how many miles you'll get out of any new tires you are considering this is called tread wear.
Much of that information is printed on the sidewalls of the tires that are on your car right now. It's also available in most owner's manuals, online, and at tire dealers. We suggest cross-checking those sources to make sure you've got the right information. Here's how to read the most important data imprinted on your tires' sidewalls.
For an in-depth look at how to read all of the information on a tire sidewall, click here. KEY: 1 Tire width; 2 Aspect ratio; 3 Radial-tire designation; 4 diameter; 5 Load rating with speed rating; 6 Heaviest spot on tire; 7 Tread-wear rating; Traction and temperature ratings; Mud-and-snow or three-peak-mountain rating; 12 Vehicle-specific marking; 13 Tire-materials list and manufacturing information.
If you're going to replace your tires with something equivalent, you will need to know the proper size. The first number indicates the width of the tire at its widest point in millimeters.
The number after the slash is what's called the aspect ratio, which indicates how tall the sidewall is as a percentage of the width.
The higher the number, the taller the sidewall. The squat tires fitted to sports cars and muscle cars, called low-profile tires, have aspect ratios of 30— Family sedans and SUVs are in the range or taller. The final number in the series is the diameter of the wheel in inches that the tire must mount to.
Sidewall cracks — Check for cuts or deformations in the sidewalls. If you see any grooves, your tire could be on the verge of a leak. Bulges or blisters — A noticeable bulge or blister could indicate a weak outer surface. This could indicate problems now and potential danger down the road. Speed rating is the approximate speed a tire can safely maintain over time. The higher the rating A is the lowest and Y is the highest , the better the handling and control.
However, a higher speed rating may result in a shorter tread life. Check with your carmaker for the proper speed-rated tire for your model. Department of Transportation tire safety standards. The higher the number, the wider the tire.
The larger the number, the higher the load capacity. H Speed Rating Speed the tire is designed to run for long periods. Choose the type of tires Now that you know tire terminology, consider the type of tire best suited for you and your car. Here are some frequently asked questions about tires: 5. Taking curves and corners fast Abrupt accelerating and braking.
This can cause excessive heat that wears the tire out more quickly Hitting curbs, potholes, etc. How do you extend the life of a tire? Can you mix tire types? Engineered for more heavy-duty applications, all-terrain truck tires are suitable for use on paved roads and for light off-road use. The more rugged tread is designed to provide added traction on unpaved and snowy roads.
Speed ratings: S mph and T mph Treadwear warranty: 50, to 65, miles Typical wheel size: 15 to 20 inches. But they typically have faster treadwear than all-season tires because the tread is specifically designed to bite into snow and ice, and the rubber is formulated to stay pliable at freezing temperatures. They are designed to be seasonal replacements for those vehicles, providing improved cold-weather grip. Speed ratings: H mph and higher Treadwear warranty: None for most Typical wheel size: 17 to 20 inches.
Speed ratings: R mph , S mph , and T mph Treadwear warranty: Typically none Typical wheel size: 15 to 20 inches. A treadwear grade is found on most new tires. But that grade is a comparative tool, and it does not tell in miles how long any one tire might last. Further, manufacturers use different methodologies in making treadwear mileage claims, which in turn makes comparing tire mileages across tire brands challenging.
Consumer Reports provides a comparative tread-life mileage figure in our tire ratings chart, offering projected mileage of all-season and performance all-season car tires. The predicted mileage is based on our rigorous vehicle treadwear test in which we run tires around the clock, over 1, miles a day. Car and truck tires are run to 16, miles.
You can check our tire ratings for details. Tire pressure monitoring systems TPMS have been standard equipment in all new cars since model year Since their introduction, government studies have found that the systems have led to a significant reduction in underinflated tires on the road, benefiting fuel economy and safety. The federal requirement stipulates that the car be able to monitor the pressure and alert the driver when it drops significantly, but it does not specify the technology.
These systems, called direct TPMS, may require batteries that must be replaced after several years, often leading to replacing the entire sensor. Some just alert of pressure loss with a warning light, but better systems provide a readout of the pressure in the tires.
Indirect systems rely on the antilock brake systems to measure wheel speed and interpret the pressure. Tires have a wealth of information encoded on their sidewalls. Load index: Shorthand for the weight each tire can carry safely. The 94 here means 1, pounds per tire—pretty typical for a midsized car tire. Standard all-seasons are usually rated T mph and H mph. Winter tires may carry the letter R mph or higher.
A grade of denotes a tire that will wear three times as well as a tire graded But the numbers are assigned by tire manufacturers, not an independent third party.
For traction, AA is best, C is worst. For temperature resistance, scores range from A best to C. Manufacture date code: Every tire has a Department of Transportation number after the letters on the sidewall. The last four digits show the week and year the tire was made; for example, the digits would signify that the tire was made during the 23rd week of Longer-lasting tires make safety checks more critical than ever. Overloading makes tires run hotter, increasing the chance of a failure.
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