Car Tires Guide: Everything You Need to Know

Quick Tips on Car Tires

Buy new tires equivalent to the originals in size, quality, performance, and load rating when replacement is needed.
The safest approach is to replace all four tires at the same time because inconsistent traction levels on each corner of the car could be dangerous.
Practicing good tire maintenance will maximize the lifespan of your car’s tires.

A car is an immensely complex amalgamation of components, each working in concert to get you and the people you love where you need to go safely, affordably, and hopefully with a little bit of fun along the way. But of all the thousands of things that make a car work, tires are the only parts in contact with the ground, and they’re what move you.

Tires also rank among the most crucial components to your safety, whether on highways or a curvy backroad.

When they need replacing, a tire shop or dealership can seem intimidating with dozens of types on the wall and an employee at a computer with a database of even more choices.

We’ll walk you through the basics of tires and help you understand these circles of rubber that keep you on the road. We’ll provide the basics, including all the types of tires available and the numbers behind them.

Types of Tires

The bad news: There are at least six types of tires common enough that the average tire shop generally has them in stock. The good news: Almost everyone needs the same type.

In a few climates, it helps to know about a second type of tire. The rest are for people who buy specialized vehicles. So, most of us can skip them. If you’re shopping for a performance car or a vehicle you’re going to take off-road, you will need to learn a few more terms. But people buying those types of cars expect the need for a bit of special knowledge.

The better news: The company that built your car almost certainly shipped it to you with the best tire choice for your vehicle. All you need to do is avoid big changes to keep things rolling.

All-Season Tires

All-season tires work like the casual shoes of the car world. They must do most things well that people need them to do. They provide a good combination of safe traction in most weather conditions, reasonably low noise, and long life at a moderate price.

Most new cars come from the factory with all-season tires. When all-season tires wear out, most people get another set and continue driving safely. They are usually sold according to how many miles they are expected to last in normal driving.

High-Performance All-Season Tires

These are the cross trainers of tires. They come standard on many sports cars. Their rubber is a bit softer than what’s used to make standard all-season tires, so they grip the road a bit more. But they last about two-thirds as long as the more common all-season tires and cost a bit more. Could you improve your family sedan’s performance with a grippier set of high-performance all-season tires? Probably. But you’d spend more up front and have to spend it again sooner.

High-Performance Summer Tires

The halfway point between an all-season tire and a racing tire, high-performance summer tires are like good running shoes for your car. But this is where our shoe analogy falls apart.

Changing your shoes several times a day is no big deal. Changing your tires several times a season is time-consuming and costly. In mild climates, high-performance tires may serve all summer long. But when steady rain or any snow is a possibility, they won’t do. So most consumers don’t buy them or only use them on a sports car kept around as a second vehicle. They are rarely the right choice on a daily driver.

These are faster and made of softer and stickier rubber than all-season tires. They’re safe enough in light rain but lose traction in heavier storms and are simply unsafe in cold weather.

Ultra-High-Performance Summer Tires/Track Tires/Racing Slicks

Returning to our shoe analogy after it fell apart, these are the highly specialized track shoes you see Olympians running in. Ever notice how those athletes put their shoes on after they step on the track, and take them off before they step off of it? They do that because they’re not practical for walking around in, and to preserve them because they are pricey.

The highest-performance tires are much the same. Soft and sticky, they will make an exotic car or highly tuned race car stick to a smooth track even against the g-forces generated in a hard turn at high speed. They can cost more than double the amount of an all-season tire. More importantly, from a cost standpoint, they wear so quickly that tire manufacturers often don’t bother putting a mileage rating on them. Most readers will never have a good reason to invest in a set of ultra-high-performance summer tires.

Winter Tires

Winter tires work like the snow boots of the tire world. They’re a fantastic idea if you live where snow regularly falls when you’re trying to get around. They use rubber compounds formulated to grip well even when frozen, and deeper tread or stud patterns that let them grip in slush. All-season tires are enough for you if you live where snow happens infrequently. But if you live where driving in snow is common, you’ll want to invest in a set of winter tires.

Consumer Reports testing has even shown that, in some circumstances, a front-wheel-drive (FWD) car with winter tires has more traction in the snow than an all-wheel-drive (AWD) car with all-season tires. Since all-wheel-drive systems can add thousands to the cost of a new car, many consumers might save money and drive safer in the snow by choosing winter tires instead. Of course, an all-wheel-drive car with snow tires works like the grippiest of grippy cars in a winter storm.

If you buy winter tires, you’ll want to change them when the weather gets warm. The same rubber formulas that hold up well in the cold wear fast in warmer weather. Driving on your snow tires in spring or summer will just wear them out quickly.

If you choose to own one set of tires for winter and another for the other three seasons, many tire shops will happily store the set you’re not using for a small fee. After all, that means you’re coming back to pay them to swap them out again.

MORE: AWD vs. 4WD: Which is Better?

All-Terrain Tires

All-terrain tires are the hiking boots of the automotive world. Typically found on trucks and SUVs, they have much deeper tread patterns to retain grip even in the mud.

Can you add all-terrain tires to your compact sedan to give it off-road chops? Probably not without making a lot of other expensive changes first. Tire shops usually stock them only in the larger sizes needed for trucks and SUVs. So you’d need larger wheels, not just larger tires.

All-terrain tires sound noisier than other tires and provide a bumpy, hard ride on smooth roads. But they’re the only choice if you’re outfitting your Ford F-150 Raptor, Jeep Wrangler, or other off-road-oriented rides.

Run-Flat Tires

Run-flats are not actually a separate category of tire. High-performance, all-season, and winter tires are available in run-flat styles. A run-flat tire has an internal support structure that allows it to continue driving safely for a certain distance even after it has been pierced. Run-flat tires, however, cannot drive at all speeds or indefinitely after losing air. They are designed to get you safely to a place where you can have the tire repaired or replaced.

Many luxury vehicles today come equipped with run-flat tires. Some even lack the accommodations to mount a spare tire, requiring drivers replace their run-flats with more run-flats when they wear out.

Run-flat tires cost more than ordinary tires but can give drivers peace of mind. They can be slightly noisier and give a slightly rougher ride, but many drivers find the changes undetectable.

Airless Tires

While the types of tires above use air, Michelin is developing a new concept aluminum tire that is not only airless but puncture-proof as well. Michelin expects its airless tires to hit the car market soon. Bridgestone, too, is working on producing airless tires for the car market.

Airless tires, already used on golf carts, would be revolutionary for cars. Using tires requiring no air eliminates flat tires and the costs associated with them. Both companies announced their tires will be eco-conscious, as they will be made from recycled material.

How to Know What Type of Tires Your Car Needs

In general, the owner’s manual specifies the type of tire the car requires. Manufacturers suggest you use tires equivalent to the originals in size, quality, and performance when replacement is needed.

Following that recommendation means you’ll replace high-performance tires on your sports car with a new set of high-performance tires. Electric cars also require special tires to handle the torque from the electric motor and the substantial weight of an electric vehicle’s battery. Always look for specifications in the owner’s manual.

However, some decisions regarding the type of tire for your car are based on your region’s climate. For example, drivers in Vermont might use winter tires during the cold months, while all-season varieties are likely the only type you need for your car in Mississippi.

How to Read Tire Size

Everything you need to know about a set of tires is written on the sidewall of the tire itself. But there’s usually no table to explain what you’re looking at. A code indicates the various sizes and ratings of the tire. The code follows a pattern like the following:

Here’s how to break down this example:

P 225/45 R 18 95 H

Tire type	P	“P” stands for Passenger. If you’re not driving a commercial vehicle, you probably see only Passenger (P) and Light Truck (LT) tires.
Tire width	225	This is the tire’s width in millimeters.
Aspect ratio	45	45 is the ratio of the tire’s height to its width. In this example, the height is 45% of the tire’s width.
Tire construction	R	The R means the tire has radial construction. The rubber cords are laid out radially, 90 degrees from the direction of travel. Almost all passenger vehicle tires are built this way.
Wheel diameter	18	This number is the diameter of the wheel the tire is mounted on, in inches.
Load index	95	Load index is a measure engineers use to show the maximum weight the tire can support. A load index of 95 can hold up to 1,521 pounds.
Speed rating	H	Speed rating is the maximum speed the tire can safely travel according to the manufacturer. An H speed rating means it can travel up to 130 mph.

Tire Terms

You may encounter some of the following terms, and we define them so you’ll be prepared when tire shopping.

Air Pressure

A measure of the pressure exerted outward on your tires by the gas contained inside them. Most tires are filled with air. Some luxury and high-performance car manufacturers prefer to fill tires with nitrogen, which escapes naturally through the pores in rubber more slowly than air. But nitrogen and compressed air perform roughly the same in tires. It’s fine to top off a nitrogen-filled tire with compressed air as needed.

Load Index

A numerical code that shows how much weight a tire can support when properly inflated. Casual drivers do not need to memorize the load index scale to buy tires safely.

Manufacture Date Code

All tires built after the year 2000 include a date code showing when they were manufactured. The first two digits of the code indicate what week of the year the tire was produced while the last two digits show the year.

Speed Rating

An alphabetical code number shows the maximum speed a tire can safely drive. Casual drivers do not need to memorize the speed rating scale to buy tires effectively.

Tire Pressure Monitoring System

Modern cars have sensors that track air pressure within the tires and will activate a light or symbol in the driver’s instrument cluster to warn if a tire is low.

Traction Rating

United States Department of Transportation (DOT) requires tires to carry a coded rating determined by a traction test on a wet surface. Tires are graded from AA (best) to C (worst) on how well they maintain traction during a straight-line braking test.

Temperature Rating

The same regulations require a code showing the speed at which a tire can become too hot to function properly. All tires sold in the U.S. are rated to function properly at least 85 mph (a rating of C).

Treadwear Grade

DOT regulations require tires carry a code showing the rate at which their tread wears compared to a standardized test tire. A grade of 100 means the tire should last as long as the standardized test tire. A grade of 200 means it should last twice as long. Tire manufacturers have frequently complained this test is not particularly useful, and few consumers know what it means.

Treadlife Warranty

Many tires come with a warranty promising they will last a certain number of miles under ordinary driving conditions. These warranties can be useful to give you a ballpark understanding of how long a particular tire may last. But should your tires fail early, they can be difficult to collect on and only pay out a small percentage of the original purchase price.

Does Tire Size Matter?

Automakers engineer each car to work with a specific size and type of tire. It is possible to mount tires of a different size than your car was designed for, but you should do so only with the knowledge that you are changing how well your car will function.

Changing your tires’ width or aspect ratio can cause obvious problems like tires that rub against the suspension. It can also cause invisible problems — adding more wear and tear to the transmission and engine, changing the amount of weight a truck can carry or tow, or even making your speedometer inaccurate or your anti-lock brakes ineffective.

Of course, you’ve probably seen off-road vehicles or muscle cars with non-standard tire sizes on the road. It is possible to safely make those changes.

Larger tires on a truck or off-road SUV can improve the vehicle’s ground clearance and change the approach, departure, and breakover angles that drivers need to know to get out of tough spots when rock crawling.

Wider tires on the rear wheels of a rear-wheel-drive performance car can give it a faster start, useful for short, straight-line spurts of speed like those in drag racing. But the added weight and grip can make a car’s fuel economy worse.

A reputable shop can safely put tires of a different size on most cars. However, it takes a lot more work and costs a great deal more than simply buying the new tires themselves. It can evolve by replacing the wheels the tires ride on, changing brake components, altering the differential on an all-wheel-drive or 4-wheel-drive (4WD) vehicle, and reprogramming or swapping out a car’s computers to ensure critical safety functions aren’t compromised.

Although those buying a vehicle for a specific use, like off-roading or drag racing, may find that cost worthwhile, it’s probably wasted on your daily driver.

When to Replace Your Tires

You should replace your tires when they are too damaged, too worn, or too old to drive safely. The cost of new tires depends on many factors. For a typical family sedan, expect to pay about $175 per tire. Always shop around for discounts and special offers.

It’s easy to repair most minor tire damage caused by running over nails or screws. A tire shop — or a home mechanic with a few basic skills — can plug a puncture hole in a tire, often for less than $20 (see how much tire repair may cost in your area).

But damage to a tire’s sidewall can threaten the structure of a tire. That kind of damage can occur if you brush up against a curb at high speed or run over an object at an awkward angle. A tire with a weak or damaged sidewall must be replaced to avoid a dangerous blowout.

Most tires are considered too worn to drive on at all when the tread is less than 1/16 of an inch. You should replace them before they get to that point. We recommend tire shopping when the tread depth on your tires reaches 1/8 of an inch.

There’s a remarkably easy test for this: Fit a quarter in the central groove of the tread with George Washington facing you and the top of his head pointed toward the center of the tire. If you can see the top of his head, you have less than 1/8 of an inch of tread depth left, and it’s time to start tire shopping at your local automotive dealership service department or tire retailer.

A similar test using a penny is not a reliable measure of safety. If you can see the top of Abe Lincoln’s head, you have less than 1/16 of an inch of tread depth left, and your tires are unsafe to use. Replace them immediately.

Rubber loses strength over time, even sitting unused. You should replace tires more than 6 years old, even if they have plenty of tread left. Check the remaining tread and tire age before buying a used car from a dealer or a private seller.

Should You Replace All Four Tires at Once?

If you get one flat tire, do you really need to buy four new ones?

This depends on the condition of your other tires, and the type of vehicle you are driving. If your tires are relatively new and still have much of their tread intact, you can usually get away with buying one tire of the same or a very similar model to replace the damaged one.

However, if you get a flat while driving on an older set of tires, the safest approach may be to replace them all. Having inconsistent traction levels on each corner of the car could be dangerous.

Some all-wheel-drive vehicles require that you replace all four tires at once. In an all-wheel-drive vehicle, the reduced diameter of a lower-tread tire may cause it to spin faster than a new tire. All-wheel-drive vehicles are designed to move the wheels at different speeds for short periods of time to provide the most traction possible. But their components can wear out quickly or be damaged trying to compensate for mismatched tires for days at a time.

Are Used Tires Worth the Savings?

About 10% of the tires sold in America each year are used. While it’s possible to buy a safe used tire, we strongly caution against it for one simple reason: Used tires are almost entirely unregulated in the U.S. There is simply no way to verify whether a used tire shop is lying about the condition or age of its products.

That means there’s no agency verifying that the tires you buy used are safe, and you have almost no recourse as a consumer if they fail. What’s worse is if the used tires fail and cause a fatal accident.

Checking for Tire Recalls

The DOT regulates tire production and sales and tracks complaints about brands and tire models. Sometimes, regulations require a manufacturer to recall defective tires and repair or replace them.

Use our research tool to check for any manufacturer recalls on your car. Recall repairs are always free.

Many cars may be subject to a recall at some point in their lives. By law, manufacturers must notify owners of recalls by mail. However, they don’t necessarily have accurate addresses for everyone.

Rotation, Alignment, and Tire Maintenance

To ensure the maximum life for your tires, you must include them with your vehicle’s routine maintenance. This occasionally requires that you spend money on minor tire services. But, done properly, this should save you money over time. Properly maintaining your tires is a lot less expensive than replacing them often because they weren’t taken care of.

There are three common maintenance procedures for tires:

Tire Rotation

Tire rotation doesn’t refer to spinning your tires, but rather dismounting them and remounting them on different wheels. Front tires and back tires wear differently, as front tires steer your car. To keep them wearing consistently, you must move the back tires to the front and the front tires to the back on a regular schedule.

Find the schedule in your car’s owner’s manual. Most manufacturers suggest a tire rotation about every 5,000-7,000 miles. Use our car maintenance tool to determine what other types of interval service you may need for your car.

A tire rotation generally costs less than $75. Our auto repair pricing tool can give you a more precise regional estimate for your make and model.

Note: Some sports cars or other special-use vehicles have different tires on the front and rear axles. Your car’s owner’s manual will tell you what to do in this case.

Wheel Alignment

When your car left the factory, its wheels were pointed in the same direction. Over tens of thousands of miles of driving, turning, and hitting potholes, the many moving joints in your car’s suspension and steering may have moved subtly out of alignment. It is often necessary to have a mechanic adjust them to ensure that they point in the same direction.

Most manufacturers recommend a wheel alignment every six months or 6,000 miles, or any time you get new tires. An alignment generally costs between $100 and $200.

Check our Service and Repair Guide to find out how much a wheel alignment costs for your vehicle.

MORE: Wheel Bearing: How Do I Know if I Need a Replacement?

Tire Balancing

On fitting new tires, a shop will install small weights inside the wheels to limit vibration. Tires should be rebalanced every time they are dismounted and remounted and can be rebalanced to stop a vibration if you notice one while driving. A tire balancing service generally costs $75 or less.

All About Tire Pressure

It’s important to keep your car’s tires near a specific pressure rating to perform safely. This pressure rating is usually found on a placard or sticker on the inside driver’s door for easy reference.

Since 2007, federal law has required all passenger cars sold in the U.S. to have a Tire Pressure Monitoring System (TPSM) that alerts drivers when tire pressure is low. In older cars, it’s a good idea to check tire pressure with a simple, inexpensive gauge at least once a month.

Tires will gain or lose pressure naturally as the weather changes, requiring you to top off the pressure occasionally. This is easy to do with the air compressors found at many gas stations.

One note of caution — most gas station air compressors have a pressure gauge mounted to the nozzle, but we don’t recommend relying on it. Since these are used repeatedly by dozens of people each day and rarely replaced, they are often worn and inaccurate. It’s best to refill the air with the compressor, but check the pressure with a gauge you keep in your glove box for this purpose.

Improperly inflated tires are dangerous. Underinflated tires have too much of their surface in contact with the road, which can cause them to overheat. Even in a best-case scenario, underinflated tires wear more quickly than they’re designed to. In a worst-case scenario, they can heat up while driving and burst.

Overinflated tires have too little contact with the road. They can lose traction, making your car difficult to control. They can increase braking distance, making you more likely to slide into the car in front of you.

How Long Do Car Tires Last?

There isn’t a clear-cut answer regarding how long tires last. Depending on the tire, most will last three to four years, provided you keep the tires properly inflated to the proper pressure for your car listed in your owner’s manual. Then, it’s important to keep the tires rotated and aligned according to the schedule in the manual and get them rebalanced any time you notice a strange vibration.

An inexpensive tire might have a 50,000-mile warranty.

How to Make Your Tires Last Longer

Suppose the treadwear warranty says your new tires should last 70,000 miles. That warranty assumes that you will care for them properly. Maximum tire life requires good care.

The tires in this example are more likely to last 70,000 miles and beyond if you keep them inflated to the proper pressure, follow a rotation schedule, maintain alignment and balance, and avoid rapid acceleration and braking. Taking it easy on the road brings longer tire life.

Even if you care for your tires perfectly, you may still run over a nail, hit a pothole, or otherwise find yourself driving on a flat tire. To prevent additional damage, take care of that problem immediately by following the steps in our tutorial, How to Change a Tire.

Bottom Line on Car Tires

Car tires are arguably the most critical safety component of your vehicle, being the sole connection to the road. Understanding the various types, knowing how to interpret their sidewall codes, and performing regular maintenance — including correct inflation, rotation, and alignment — are crucial steps every driver should take. Investing time in tire care and replacing them promptly when worn, damaged, or too old is a direct investment in your safety and your vehicle’s performance down the road.

Editor’s Note: This article has been updated since its initial publication.