Your tires — they are the only part of your vehicle that makes physical contact with the road. As such, it makes dollars and sense to have well-functioning, safe, properly inflated tires. Even so, tires are nothing more than an afterthought for many drivers — until there is a problem. Fortunately, you don't have to be stuck on the side of the road with a blowout to know it's time to replace your tires. In fact, several indicators and signs can alert you that it's time to replace your tires. Let's take a closer look at some of the top questions you should ask to determine if it's time to replace your tires.

A Penny for Your Thoughts & Your Tires

Did you know one of the easiest ways to determine if you need new tires is by using a penny? As crazy as it sounds, you can use a penny to quickly and easily perform a test to gauge the usefulness of your tire treads. Simply take a penny — head down— and place it into several grooves across the treads of your tire. If you can see the top of Lincoln's head, your treads are too worn and shallow. This means you should go ahead and replace your tires.

On the other hand, if Lincoln's head is covered by the treads, you probably don't need new tires. When Lincoln's head is covered, you have over 2/32 of an inch of tread remaining. While the method can be relatively effective, it's not scientific. And in the event it's close, you should bring your vehicle to Federico Kia for a professional tread inspection.

Do You See Cracks in Your Tires?

While the penny test can measure tread depth, there is a simpler test to measure the fitness of your tires. Quickly look at your tires, especially the sides. If you notice any holes or cracks in the tire, you have sustained irreparable damage. Anytime you notice these cracked tire indicators, it can be a dangerous precursor to a blowout. As a result, you must have your tires inspected and/or replaced as soon as possible. It could also indicate your tires are leaking steadily. In either case, you should have your tires inspected promptly.

Are Your Tires Bulging?

When you look at your tires, you should see surfaces that are consistent and without bulging. If you do notice any bulges or bubbles in the sidewalls, you should have your tires inspected immediately. Simply put, bulges in tires can lead to a blowout. A bulging sidewall typically means there is a weak spot on the surface of the tire. This phenomenon is almost identical to hernias humans can have in their abdomens. Because it can make your tire subject to blow at any time, a bulge shouldn't be taken lightly. You should have the tire replaced as quickly as possible.

Are Your Tires Long in the Tooth?

Even if you have no bulges, good tread depth, and no cracks, you may need to replace your tires based solely on their age. Most vehicle manufacturers suggest you replace your tires at least every six years. On the other hand, some tire manufacturers recommend your tires be replaced at 10 years. Because each manufacturer's suggestions can vary, it's best to check the recommendations. However, if your tires are more than 10 years old, it's time to replace them.

Do You See the Cords on Your Tire?

Tire tread wear is one thing, but if you can see the cords, your tires are well past their expiration date. Underneath the tread of your tire are polyester or metal cords. The cords are designed to provide support for the overall structure of your tire. And if you do see cords, it means that you have no traction in that specific part of the tire. It also means that your tires are not road safe and should be replaced yesterday.

Have You Racked Up the Mileage?

Similar to the age of the tires, there are no hard and fast rules as to the exact number of miles before you should replace your tires. While some manufacturers will offer a 30,000-mile warranty, others may offer up to 80,000 miles of warranty coverage. However, most tire manufacturers tend to warranty their tires for around 60,000 miles. Comparing the warranty coverage to the actual number of miles you have on your vehicle can indicate whether they should be replaced. For example, if your tires are covered for 30,000 miles but you have driven 80,000 miles on them, you most likely need new tires.

All-Season Tires

The vast majority of vehicles today come with all-season tires, which are designed to provide acceptable all-around capability throughout the year and in all weather conditions. That means a reasonable ride and respectable handling, quiet running, good wet-weather grip, and some capability in snow. Given their all-season designation, most car owners leave them on in winter and expect that their tires will deliver all the traction they need on snowy, icy roads. But most all-season tires are marginal in snow; dedicated winter tires, also known as snow tires, provide far better traction when the snow falls.

High Performance All Seasons & Grand Touring All Season Tires

There are now two main sub-categories of all-season tires: high-performance all-seasons and grand touring all-seasons. High-performance all-season tires provide sharper handling than "standard" all-season tires. They grip the road more confidently and feel more sporty to drive—usually at the expense of some winter-weather traction. These tires are intended for sportier cars and more-aggressive drivers. Grand touring all-season tires have the lower-profile look of high-performance all-season tires but ride better at the price of some handling ability.

Recently, a subset of grand touring all-season tires has emerged that we call "all-weather" tires. 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.

Summer Tires

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. Summer tires come on cars such as Porsches, Corvettes, Mercedes-AMGs, and Mustangs.

Winter Tires

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.

A new set of tires can do wonders for your car's handling and traction. But for a new set of tires to work effectively, they need to be installed on your vehicle properly. Tire installation involves more than simply trading one set of tires for another. It also involves making sure the tires are correctly mounted on the wheels and properly balanced. In some cases, a wheel alignment might also be part of a tire change.

While tire installation is a job best left to professional, certified technicians, understanding the steps involved can help you get a better sense of what's required to take the best possible care of your vehicle.

Removing and Inspecting the Old Tires and Wheels

The first step when installing new tires is to take the old tires off of the vehicle. To do that, the technician will mount your vehicle, lifting the wheels off of the ground. After the car is lifted, the technician will use a wrench to loosen the lug nuts that attach the wheel to the car. When removing the tires and wheels, the technician will typically start with the front wheel on the left side. They'll work counterclockwise when taking the wheels off of the car.

Mounting the New Tires

After the tires and wheels are taken off of the vehicle, the next step in the process is to deflate the tires. The technician will loosen the valve stem core to let the air out. Once the tires are fully deflated, they can be taken off of the wheels. Usually, the technician uses a special machine to take the tire off of the wheel rim.

The technician is likely to inspect the wheels and lug nuts during this phase to make sure there aren't any signs of damage. It's particularly important to inspect the rim to make sure it doesn't have rough spots or areas that could scratch or puncture the new tires. If the rim is very rusty or very worn out, your best option might be to replace it with a new wheel.

After the old tires are removed, the next step is to place the new ones on the wheels. Usually, it's a good idea to replace all four tires on a car at the same time, so the technician will most likely be working with all four wheels of the vehicle. The price of new tires isn't often included in the tire installation cost, so it's something to pay attention to separately. Right before installing the tires on the wheels, the technician will place a new valve stem. Each tire will be attached and sealed to the wheel, then inflated.

Balancing the Tires

The tire change cost usually includes the cost of balancing the tires on the wheels. Tire balancing is important, as it helps to reduce wear on the tread of the tires and allows a car to grip the road smoothly.

A technician will use a tire balancer to measure the imbalance in each wheel. While using the machine, the technician will place or adjust tire weights on the tire to help improve the balance. Balancing is usually included in the tire installation price.

Installing the Wheels

After the tires are balanced, the next step is to install them and the wheels back on the vehicle. The technician will use a wrench to tighten the lug nuts. While the vehicle is still elevated on the lift, they won't fully tighten the lug nuts. Instead, they'll bring the car down until the wheels just touch the ground. Once the car is lowered, the nuts will be completely tightened with a torque wrench.

Aligning the Wheels

Wheel alignment doesn't need to be performed at the same time as tire installation, but it's sometimes recommended. While tire balancing adjusts the weight distribution of the wheels and tires, a wheel alignment focuses on adjusting the suspension of your vehicle so that the car handles better and is less likely to pull to one side or the other when you're driving.

It's usually a good idea to have a wheel alignment performed if you've started to notice problems with the steering. For example, if the steering wheel often turns to one side even when the car is driving straight, that's usually a sign that something is wrong with the alignment. The steering wheel might shake if the wheels aren't properly aligned. Uneven wear on the tires is another sign that the alignment needs adjusting.