The penny test has long been the gold standard for determining tire well-being. Slip the coin in the tread. If you can see the top of Abe Lincoln's head, it's time for new tires.
In the past few years, though, safety experts have hit drivers with a bit of inflation. As it turns out, a quarter is a better means to measure tread, according to online retailer Tire Rack.
The traditional penny test ensures tires maintain 1/16 inch of tread, but tires that pass the quarter test have at least 1/8 inch of tread gripping the road -- and that extra bit of rubber makes a big difference on rainy days, according to a 2007 study from the tire retailer.
The premise is simple: The deeper the tread the better the traction.
Whether you plan to replace your tires when you see George Washington's head or you're holding out for Lincoln's shapely noggin to show, sooner or later you're going to need new treads, and how you drive will dictate your choice in tires.
"Since tires are the only parts of the vehicle that make contact with the road, take this purchase seriously," says Barbara Terry, automotive advice columnist and author of "How Athletes Roll." "Visit a couple of tire dealers in your area. If they don't ask questions about your driving style and habits and simply jump to a conclusion and price, then they're not really helping you get the best value for your money."
Do you just need to get from point A to point B during your daily commute? Do you have a need for speed? Do you simply crave better handling on wet and icy roads?
"Overall, the tire has to match your driving pattern and vehicle," says automotive consultant William McGowan, who has worked with nearly a dozen auto manufacturers, including Hyundai, Honda and Lexus. "The different categories allow for specialization. You wouldn't wear Reeboks with Vera Wang. A Ford Fusion tire is not going to need the rating that a Porsche tire would. For most people, tires follow function."
Most cars come factory-equipped with all-purpose tires, which offer year-round traction and capable handling in both wet and dry road conditions.
Designed for long tread wear, a comfortable ride and low noise, they're often the most cost-efficient option and the best bet for commuters, but specialized drivers may want to look beyond the basics.
High-performance and ultra-performance tires are built for speed. They typically have lower and wider profiles than all-weather tires and feature softer rubber for better grip.
Performance tires are designed for quick acceleration, responsive steering at high speeds and better braking but often sacrifice driving comfort, tread wear and wet weather control. However, several brands now offer all-season performance tires, aiming to balance the tires' responsiveness in rain and snow.
A popular choice in cold climates, winter weather tires have tread designed to grip in snow and ice and rubber formulated to stay flexible in low temperatures. They tend to have much quicker tread wear than other models, though, so drivers often swap them out come spring.
"You put them on in the wintertime and take them off in spring. Depending on how many miles you put on them, you may get up to four seasons out of them," Terry says.
With an increased eye to fuel efficiency, several of the big-name brands offer tires designed to put money back in your pocketbook.
"A fuel mileage tire literally works for you and can save you money at the pump," Terry says.
These tires couple low rolling resistance with all-weather handling, which means it takes less energy to push the tires down the road, but drivers still get the grip they need to maneuver wet and icy roads.
The savings are small -- according to Consumer Reports, a 10 to 20 percent difference in rolling resistance might add a 2 percent increase in fuel economy -- but when gas prices hover around $3 a gallon, every bit helps.
Don't discount the discount tires. When it comes to new treads, cost isn't as important as finding the right tire to suit your driving style.
"Price is mostly indicative of advertising budgets and brand name, and many manufacturers put out the same tire with different names," McGowan says.
Check the ratings, and be sure the tires are backed by a reputable dealer. Also, look for brands that offer road hazard replacement. Beyond that, let your budget be your guide.
"You might be surprised to learn, for example, that a lesser-known brand such as Hankook has received consistently good reviews when compared with Goodyear and Michelin and yet typically costs 10 to 15 percent less," Terry says.