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When to Replace Your Tires

By Larry Carley copyright AA1Car.com

replace worn tires

Like brake pads, tires wear out and eventually have to be replaced. Most quality brand passenger car tires should last upwards of 60,000 miles with normal driving. Tires can wear out sooner if you drive aggressively, if you don't check the air pressure in your tires and they are underinflated, or if your vehicle has worn or misaligned steering or suspension parts.

Most new passenger car tires have a thread thickness of 10/32 to 11/32 inch (8 to 8.7 mm). Depending on the tread compound, the tread will wear down about 1/32 inch for every 5,000 to 8,500 miles of normal driving. Consequently, a new set of tires may last 40,000 to 70,000 miles on average.

As the tread wears down, the depth of the grooves between the treads becomes shallower. This increases the risk of hydroplaning during wet weather because water becomes trapped under the tire. Worn tires also have less traction and grip on snow and mud, and worn tires can take longer to stop a vehicle than new tires. Worn tires are also thinner tires, and are more easily punctured by road debris.

Tire Inspection

A quick visual inspection is all it takes to see if your tires are worn out. Tires should be replaced if the wear bard between the blocks of tread are flush with the surface of the tread, or the depth of the grooves between the treads is 2/32nd inch (1/16 inch) or less.

You can check tread wear by inserting a penny upside down into the grooves between the tread. If you can see the top of Lincoln's head, your tires are worn out and need to be replaced.

checking tire tread depth with a penny

Some experts now recommend replacing the tires sooner, especially if you live in a wet climate and you drive on rain-soaked roads. The grooves between the blocks of tread on your tires are there so water has a place to escape when you hit a puddle. Rain tires and all-season tires typically have wider grooves that are angled to route water out from under the center of the tire towards the edges of the tread. This helps reduce the risk of hydroplaning that could cause a loss of steering control. If the remaining tread depth is less than 4/32 inch, the tires should be replaced to maximize driving safety.

If you insert a quarter upside down into the tread, the top of Washington's head is 4/32 inch from the edge. So if you can see the top of George's head, you have about 4/32 inch of tread left.

Replacing tires with 4/32 inch of tread isn't as important in dry climates because the grooves in the tread don't have to deal with water. But in wet climates, it can make a significant difference in steering control handling and braking when the roads are wet.

Old Tires May Be Unsafe

The synthetic rubber compounds and reinforcements used to manufacture tires deteriorate with age. Many tire manufacturers recommend replacing tires that are more than six years old regardless of how much tread they have left. Why? Because the risk of tire failure goes up with each year of use. After six years, the risk of tread separation, cracking or a sudden blowout is significantly higher than when a tire was new.

Most safety experts say ANY tire that is 10 or more years old (regardless of wear or condition) is a potentially dangerous tire and should be replaced. Some countries require replacing tires when they reach 10 years of age.

Tires will age whether they are out in the elements or sitting in a garage. They will age much faster,however, when they are exposed to direct sunlight and high ambient temperatures. Dry desert climates will really accelerate tire aging, so don't put off buying a new set of tires if they are approaching six years of age.


We do NOT recommend buying the cheapest tires you can find. Economy tires may seem like a bargain, but their traction, noise level, ride smoothness, tread life and overall durability will NOT be as good as a premium grade tire. Buy the BEST tires you can afford!

As a rule, replacement tires should be the SAME SIZE and ASPECT RATIO as the original tires (unless you are changing to different sized aftermarket wheels/tires).

Equally important, the Load Rating, Temperature Rating and Traction Rating of replacement tires should always equal or exceed those of the original equipment tires.

The Load Rating is an indication of tire strength and how much weight a tire can safely carry. The Load Rating is most important with pickup trucks and large SUVs that may carry heavy loads, a large number of passengers or tow a trailer.

The Temperature Rating is an indication of how hot the tire runs and how well it can handle high ambient temperatures. A Temperature Rating of "A" is recommended for any vehicle operated at highway speeds in a hot climate or during hot summer weather. Less expensive tires will typically carry a lower Temperature Rating of "B" or "C" which are not as good. A lower Temperature Rating increases the risk of a sudden blowout during hot weather if a tire is underinflated. For this reason, we do NOT recommend buying tires that have a "B" or "C" Temperature Rating.

The Traction Rating is an indication of how well a tire grips the road. A Traction Rating of "AA" or "A" is best for both wet and dry driving conditions. Winter tires provide extra grip on wet snow and ice, and will carry a snowflake traction rating.

The Tread Wear Rating is a relative index of how long a tire should last under normal driving conditions. The higher the number (over 400), the better if you want long-lasting tires. Many performance tires do NOT have a very high Tread Wear Rating because they are made with softer rubber compounds that are formulated to maximize grip, not service life.


If you are happy with the brand and model of tires that are on your vehicle now, buy the same brand and model of tire as before. Original equipment tires are specified by a car maker to meet very specific ride, noise, fuel economy and handling criteria. So replacing same with same will usually maintain the ride, feel and performance of the tires that came as original equipment on your vehicle. However, on some vehicles (typically entry level cars and small SUVs) the car makers use less expensive tires to reduce cost. These tires typically have lower Temperature, Traction and Tread Wear Ratings). In such cases, we would recommend UPGRADING to a better replacement tire with higher ratings.

For more information about how various brands of aftermarket tires compare to the original equipment tires on your vehicle, talk to your tire dealer and ask for their advice. Or, refer to the resources at the bottom of this article.

If you are looking to upgrade some aspect of tire performance when you replace your tires (such as handling, noise reduction, ride smoothness, tire life, wet traction or appearance), the best advice is to do some research as to what type of tires might best match your expectations and how other motorists have rated such tires (read the consumer tire ratings on some tire dealer websites).

Tires come in a variety of different grades and price ranges. There are differences in temperature ratings, speed ratings, wet and dry traction ratings, tread wear ratings, tread patterns, handling characteristics, noise levels and ride smoothness.

As we said earlier, we do NOT recommend buying tires that do not have an "A" Temperature Rating, and "A" Traction Rating, or a tread wear index rating of less than 400 (unless you want a performance tire with lots of dry pavement grip).

We also recommend Speed Rated tires for all applications. Speed Rated tires are made with stronger reinforcements and higher-quality materials. For highway driving, we recommend a tire with a Speed Rating of "H" or higher (see Speed Ratings below) for an added measure of safety even if you never drive that fast.

tire sidewall information

All-Season tires are recommended for most passenger cars and light trucks used for everyday driving and commuting. Performance tires are essential for optimum handling if you drive a sporty or performance cars. Ultra-low profile tires look cool, but are heavier and stiffer than other tires and generally give a rough ride.

Should you consider buying a set of used tires? A good set of low mileage used tires that still have plenty of tread on them can be a more affordable option to buying a new tires. But used tires can be risky depending on their age and condition. The tires may have been patched, or they may have been taken off a vehicle because they had some kind of problem such as a belt separation or out-of-round condition that was causing a pull or vibration. For more information on this subject, see Used Tires.


The speed rating indicates the maximum speed at which the tire can safely handle without exceeding its design limits. A short burst of speed beyond the tire's maximum speed rating usually won't cause the tire to explode, but sustained driving at speeds beyond the tire's speed rating (especially during hot weather or when carrying a heavy load) does increase the risk of sudden tire failure.

As a rule, the higher the speed rating of the tire, the better the tire. You may never need the maximum speed rating of a tire, but a higher speed rating provides an extra margin of safety, especially when driving at highway speeds during hot weather.

AA1Car recommends a minimum speed rating of T or H for everyday driving, and a minimum speed rating of V for any performance vehicle.

WARNING: Replacement tires should always have the SAME or HIGHER speed rating as the original equipment tires on your vehicle. You can always buy a HIGHER speed rated tire, but you should never buy tires that have a LOWER speed rating.

Q : Up to 100 mph

S : Up to 112 mph

T : Up to 118 mph

H : Up to 130 mph

V : Up to 149 mph

Z : 149 mph and over

W : Up to 168 mph

Y : Up to 186 mph


Unless you are replacing your original wheels with aftermarket custom wheels that have a larger or wider rim size, you have to buy replacement tires that are the same size as the original. The tire size is printed on the sidewall of the tire. A 215/60R 16 size means the tire is 215 millimeters wide, has an aspect ratio of 60 (the height of the sidewall as a percentage of the tread width), and fits a 16-inch wheel.

Most vehicles that are equipped with antilock brake systems or stability control require replacement tires that are the same size as the original. If a different tire and/or wheel size is desired, it may require reprogramming the ABS control module and/or PCM with a scan tool so the system will work properly with the larger or smaller tires. Wider makes no difference. It's the height and circumference of the tires that affects the readings of the wheel speed sensors and vehicle speed sensor.


We have no tire brand preferences as most tire manufacturers offer competitive products. However, there can be considerable differences in tire handling, ride quality and tread life between different brands. Premium brands typically command a higher price because they are better tires.

Tire model designations are almost meaningless these days because they keep changing as fast as cell phones. If a particular model of tire is produced for more than a year , it's a long time. Tire manufacturers are constantly tweaking and altering the tires they produce. Many of these "improvements" or changes have little to do with actual performance changes in a tire, but more with marketing and repositioning the tire against competitors. This makes tire comparisons very difficult because the products are constantly changing.

Consumer Reports Tire Buying Guide does an excellent job of rating and comparing tires. They are not in the business of selling tires, so you can trust their evaluations to be unbiased and accurate.

Tire Rack also has a wealth of tire information, including consumer reviews of tires people have purchased. Just remember that Tire Rack is in the business of selling tires, so the ratings may be skewed and they may be promoting one brand of tire over another. The same precaution goes for their user reviews. A hundred people may be very satisfied with a particular tire, but one person who is not and posts a negative review can give the impression that a tire is not so good. So keep that in mind when reading customer reviews of tires.

Discount Tire is another online resource that includes consumer ratings with their tire listings. You can look up the tires that fit your vehicle, compare the brands and prices, and see what people who have actually bought and used the tires have to say about their ride, handling, noise level and performance.

As a general rule, tires that are made with softer compounds provide better dry traction, handling and braking performance, but do not wear as well as tires made with harder compounds. The design of the tread has the greatest influence on noise, while the construction of the sidewalls has the largest impact on ride smoothness. Taller softer sidewalls (higher aspect ratio) usually provide the smoothest ride, while shorter stiffer sidewalls (low aspect ratio tires) provide better cornering and handling control.]


Tire dealers can tell you which tire sizes and brands fit your vehicle, and help you decide which brand and style of tire to buy that will best suit your driving needs. If you want replacement tires that are quieter, ride smoother, handle better, provide improved wet traction, longer tread life or whatever, they will likely recommend some type of premium all-season touring tire.

Don't put too much emphasis on price. The cheapest tires are just that -- cheap. They won't last as long as a mid-range or premium tire, and they won't handle or ride as well as batter, more expensive tires. Watch for newspaper and online coupons and sales notices that can save you some bucks. Tire stores often advertise "Buy 3 get one free" offers, or special limited-time discounts on selected brands of tires that may reduce the price 20 to 30 percent or more. If you can wait for a good deal, do it!

In addition to the price of the tires themselves, you will also have to pay for balancing (mounting is usually included), new valve stems, an old tire disposal fee, and tax. If you want road hazard coverage, that will be extra, too. Road hazard warranties can be well worth the price if you puncture or damage a low mileage tire and have to replace it.

The salesperson may recommend a wheel alignment when you buy new tires. If you old tires show uneven tread wear, or they wore out unusually fast, an alignment check is a good idea. However, if you got 60,000 or more miles out of your old tires, and the tread wear was normal (no shoulder wear or uneven wear), you can probably skip the alignment check.

replace tires More Tire Articles:

Watch Out For Old Tires

Used Tires

Why Tires Fail

What To Do If You Have A Flat Tire

Run-Flat Tires

Tire Pressure Monitoring Systems (TPMS)

Tire inflation tips

Tire Valve Stems

Blame It On The Tires

Tire Wear (What to look for, how to reduce it)

Tire Rotation: When & How To Rotate Your Tires

Wheel Balancing

Wheel Alignment

Fixing Common Alignment Problems

To More Technical Articles Click Here to See More Carley Automotive Technical Articles

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