5 Questions Any Good Tire Dealer Should Ask
Tires are a big investment most people make only every few years. If you want to make the right decision, you've got two choices:
- Become a tire selection expert.
- Become a tire dealer selection expert.
Option 2 is a lot easier. Make sure the salesperson asks you these five questions:
1. "What do you use your vehicle for?"
The best tire for a commuter in an economy car may not be the same as what's needed for the family car. The tire that's best for comfort and least noise for your long-distance commute may be overkill for a third car that's used less often. If you're hauling loads or a trailer with your truck, that suggests a different choice than what's right on a truck used for lighter duty.
Road conditions are a part of this equation. If you regularly go off-road, you're driving streets with lots of potholes, or you live in a place with winding roads and tight curves, the salesperson's recommendations will differ.
2. "What are your driving habits?"
If your dealer asks this question, they're a keeper.
Literally and figuratively, tires aren't one-size-fits-all. For example, a new driver in the family can change the ideal tire. So can your tendency towards conservative versus faster driving.
3. "Will you be doing any driving in winter conditions?"
You need tires that suit the weather conditions where you drive and your dealer knows that. A good one will ask.
All season tires are the choice for drivers in sunnier places. If you're driving on snow or ice every year, you'll likely have winter tires for cold months and a different set for warmer weather. Your dealer's recommendation on what's going to last longest and perform best will also be different if you live in a place with extremes of heat and cold than someplace with more consistent weather.
4. "What's your budget?"
All these factors?driving habits, safety, longevity, comfort, handling, noise?have to be balanced with your budget. A good dealer is happy to explain the differences between a quality, basic tire, a premium tire, and everything in between, because it narrows the choices to what's best for you. You should never get the feeling the store rep is pushing a tire just because it's on sale or it's the most expensive.
5. "Here's how our warranty works…"
OK, it's not really a question. But the best dealers will bring this up. If you want to get the best value for the money, it's really important to think this through. Service warranties can include free services worth hundreds of dollars over the life a tire. They vary substantially by dealer. Some features and limitations to find out about:
- Road hazards – If you run over a pothole, nail, or debris that damages the tire beyond repair, is the value of the tire covered?
- Expiration – How long is the tire covered? Three years? Five years? The life of the tire?
- Workmanship – Are both the tire and the quality of installation/repairs covered?
- Free services – Are regular inspections for wear, tire rotations and rebalancing included? What's the cost to fix flats?
- Locations – How many stores will honor the warranty? The service warranty that comes with tires you buy at a dealer is an agreement with the dealer, not the manufacturer. A service warranty goes beyond the standard workmanship and material warranty you get from the company that made your tires. It can cover labor and free maintenance services. But your service warranty is good only at the retailer that sold you the tires. (If you're weighing buying online, consider that if you get a flat, or a tire is defective, you have to get it off your vehicle and return it yourself.)
Find the right dealer and you don't have to become a tire expert
Real professionals will be happy to talk your ear off about technical features?tread bars, siping, harmonic noise?or just give you the basic benefits of a tire in layperson's language, your preference. Make sure they're asking the questions above as a starting point. The answers will make the best choice obvious.
A Helpful Q&A Guide to Buying Tires
A lot of people choose tires based on the mileage warranty and cost. However, these are only two of many important factors to consider.
There are lots of choices between tires even at the same mileage and price point. It's important to understand key factors to have the right tire for your driving needs. Things to ask about are: tire size, performance rating, load rating, ply rating, expected mileage and tread design, so you can depend on your tires and feel safe while traveling.
Here are answers to questions people ask the most about how to pick out tires. This info won't make you a tire expert but will give you the basics when you visit your tire dealer.
Q: DO I WANT ALL-SEASON OR SNOW TIRES?
A: It depends on whether you drive in winter conditions regularly.
Tires are categorized as all-season, summer, traction, winter or highway (for light trucks). Buying a set of highway or all-season tires is a good choice if you live in a sunny, warm climate that gets occasional rain and you aren't regularly traveling on snow and ice. They perform well in climates where temperatures don't typically get below 45 degrees. All-season tires are built to handle hot pavement but don't offer the traction needed for slick, winter roads. If your area gets snow or ice every year, or if you make regular trips over mountain passes in the winter months, you'll likely need all-season tires for spring, summer and fall driving, and winter tires for more harsh conditions. Get the full lowdown on how they're different and how to choose winter tires.
Q: DO I WANT PERFORMANCE TIRES?
A: Performance tires are designed for better cornering and handling at higher speeds. If these are your priorities, talk to your tire dealer about your options.
Other specialty tires, such as traction tires for pickups and SUVs, are for off-roading, gravel and driving in mud.
Sometimes your demands are simple; you just need a quiet, smooth passenger car tire for freeway driving. All-season or all-terrain tires are made to handle year-round driving needs on and off the blacktop. A good tire dealer will ask you the right questions and know the best product for your needs and budget.
Q: DOES DRIVING WINTER TIRES IN SUMMER DAMAGE THEM?
A: Yes. With more people running studless winter tires, this is a growing issue. Winter tires are made with a special rubber compound that stays softer and more pliable in cold weather for better road grip. As seasonal tires, they aren't designed to handle the heat. All-season tires are made with a different rubber compound suitable for hot pavement.
If you use winter tires in hot weather they are going to wear out much quicker. It's important to factor in the long-term cost if you're thinking about running your winter tires through the warm months. This could reduce their life by years.
Q: IS THERE REALLY A DIFFERENCE BETWEEN HIGHER- AND LOWER-PRICED TIRES?
Tire pricing is typically based on what the tire delivers for comfort, ride quality, noise level, tread durability and traction features. Some tires for specific uses. For instance, light truck mud tires may have a higher price point because they have more rubber on them, which increases the cost to produce them. Prices also reflect the value you can expect from your tire; tread life typically ranges from 30,000 to 80,000 miles. This mileage can vary depending on whether you are looking at passenger car, performance car, light truck or SUV tires.
Q: WHO MAKES THE BEST TIRES?
A: There are plenty of well-made tires. The biggest differences often come down to the warranty. Most of what you get in a tire warranty is provided by the dealer, not the tire maker. If there's a defect in the tire you buy, that's covered by the manufacturer. However, many other warranty features are covered by the dealer that sold and installed your tires.
Tire service warranties vary greatly by dealer and can be worth hundreds of dollars over the life of a tire. A well-built tire is only as good as the warranty backing it, so consider everything that's in the warranty. Here's a list of what to look for:
- Length of coverage. The best warranties extend for the full life of the tire's tread mileage guarantee, not a set number of years.
- Workmanship. Both the tire and the quality of installation/repairs should be covered.
- Free care. Whether flat repairs, regular inspections for wear, tire rotations and rebalancing are free.
- Road hazard coverage. If you hit debris or a pothole and the tire is damaged beyond repair, is the value of the tire covered?
- Convenience. How many locations honor the warranty.
Be careful about buying extended tire coverage, like tire certificates, which replace your tires for free if you ruin them. It's very rare to damage multiple tires beyond repair over the life of the tires. Usually, damage to a tire can be repaired and often it's a single tire that's involved. By the time you add up the cost of covering your tires with certificates, you could pay for any tire that gets damaged.
There are other drawbacks as well. Tire replacement certificates often expire after three years. And some aren't honored if the damage comes from running your tires at the improper inflation.
Q: CAN I CHANGE MY TIRE SIZE?
A: Swapping out your tires for bigger or smaller ones than what came new on your vehicle is a fun way to change your ride's look. Understand that it may affect performance. Be aware that when you change to a taller tire, your speedometer will read slower than you're going because your tire is spinning fewer revolutions per mile (RPM). You may get more road noise and differences in the way your vehicle handles.
In contrast, lowering the profile of your car or truck by using a smaller tire size will alter both handling and how much clearance you have. You may bottom out on hills that you used to clear just fine and it may stiffen the ride.
You can use a tire size calculator to see how different sized tires will affect your RPMs and tire speed, but such tools are only estimates.
Be sure to cover all the unknowns by talking with a tire professional before you change sidewall height or tread width. An expert will know how to translate the difference in RPM, tire speed, load index and speed rating into what it will mean for your vehicle and driving. They'll also explain how the tires or wheels you have your eye on will or won't fit with your vehicle's suspension, gearing and bodywork.
Q: IS IT OK TO REPLACE ONE TIRE AT A TIME?
A: It's best to consider replacing tires in pairs, but read your owner's manual. Even small size and type differences between your four tires can have big consequences, especially if you own an all-wheel drive (AWD).
Replacing one tire with a different brand, model, size or tread depth can cause a noticeable pull in the steering wheel or other handling issues. There are tight tolerances for AWDs, so they're at greater risk for such problems.
A big difference in tread depth between tires can damage expensive parts. It is always a good idea to review your owner's manual to see if the vehicle manufacturer has a point of view on this.
Q: WILL BUYING TIRES ONLINE SAVE ME MONEY?
A: It might save you some money if you're a tire expert and have a place that will mount the tires on your wheels. If not and you don't, you run the risk of getting the wrong type of tires for your vehicle and driving. Then that Internet bargain can add up to a lot more hassle, time and money than expected.
Another issue is finding a tire dealer that will service your tires by mounting and balancing them on your wheels at a reasonable cost. This can get expensive if you're changing out summer and winter tires twice a year. Here are some cost and warranty factors to consider when you're thinking of buying online.
Do I Really Need an Alignment?
Alignment assures your tires meet the road at the proper angle, your wheels are pointing straight and your tires are centered in the wheel wells. It adjusts the angles of your vehicle's wheels to original specs for best gas mileage, proper road contact, a smooth ride and longest tire life.
The most common signs of misalignment are pulling to one side while you're driving, unusual tire wear and a steering wheel that's off-center even though your vehicle is pointed straight. But these symptoms can have other causes, sometimes simpler and sometimes not.
Steering pull can be caused by road conditions. If the asphalt has grooves that are slightly farther apart than your car's axles, you may feel a pull as the tires on one side ride slightly higher. If the road is noticeably higher in the center, the vehicle may veer as the tires try to find a level surface.
Torque steer is a pull that happens during acceleration, from a difference in power being delivered to the wheels. A pull only during braking is probably from a caliper on one side sticking and not fully disengaging from the brake disc. A failing tire and improper tire rotation are two more causes of steering wheel pull.
Poor alignment may not be the issue if your steering wheel sometimes tugs in one direction and then the other. A bent or worn suspension part - ball joints, strut bearings or tie rods - could be to blame.
Atypical tire wear may be the result of worn shocks or struts, bushings or springs, or from carrying heavy loads (all of which can also put your vehicle out of alignment). Uneven wear can also be caused by driving on over-, underinflated or imbalanced tires.
An off-center steering wheel can be caused by worn steering or suspension parts. Just getting an alignment won't fix the root cause.
One last common point of confusion: Vibration while underway is often a symptom of out-of-balance tires, not bad alignment.
When We Recommend an Alignment
An alignment is important to do when:
- You get new tires.
- You lower or lift your vehicle.
- Suspension parts that affect the tire angles are replaced or adjusted.
- You've had a fender-bender or a hard impact with a curb or road debris.
- It's been a year since your last one.
Tire stores strongly recommend an alignment after installation of new tires because they want you to get what you pay for: full tread life. They also want to be sure that any defect that becomes apparent during the warranty period is from a manufacturing issue, not from wear that could have been avoided with basic vehicle maintenance.
Lifting or lowering a vehicle will affect your toe, camber or caster angles. So will repair or replacement of suspension and steering parts - struts, shocks, ball joints, tie rods, bushings or control arms. If one of these components is damaged, it's a pretty good bet your vehicle's alignment is out of spec. If you don't fix them before your vehicle is aligned, you'll soon have the problem recur.
Alignment checks are always advised after any significant impact with a bumper, a curb, a big pothole, an animal or anything else. It may have knocked your vehicle off spec.
Also, get a check annually, or twice yearly if you typically travel on rough roads. Regular checks are important because off alignment isn't always obvious. The wrong toe angle can go unnoticed and so can atypical tire wear. Cars usually go out of alignment gradually, so you may not realize how much it was impacting drivability, gas mileage or tire wear until it's corrected.
Tips Before Getting Service
Because the measurements are very fine, misalignment is not something you can see by just eyeballing whether the wheels and tire angles look right. But an experienced tire technician will usually know if you're overdue for an alignment just by looking at your tire wear.
Here's what to know if the service is recommended:
- If you have a damaged suspension part, replace it first. Worn or bad parts will put your vehicle right back out of spec.
- The technician may recommend a thrust alignment or a four-wheel alignment. Here's a primer to understand what they're talking about.
- Before service, let the tech know you'd like a printout showing what your alignment measurements were prior to the work being done and the final settings for your records. You can verify the job was truly necessary. Here's an example of what you'll see.
Measurements before alignment:
Measurements after alignment:
Looking at existing tire wear is one way to identify misalignment but the ideal is to correct your wheel's positions before you have early and unnecessary tire wear. Regular alignments are part of basic maintenance that helps you get full mileage out of your tires.
Do You Even Need a Spare Tire?
The fact that spare tires are no longer standard equipment on many newer-model cars can come as a nasty surprise when you get a flat tire. While most new light trucks and larger SUVs still come with a spare, here's important news:
About 35 percent of vehicles now come from the factory without a spare tire.
Getting a flat tire is a major hassle and it can be costly. Here's what to know about spares, including why more autos are coming without them, how to decide if you really need one and the upsides and downsides of inflator kits.
Which New Car & SUV Models Don't Include a Spare?
On May 23, 2015, my 7-year-old granddaughter, my friend and I were stranded for four hours on I-84 west of Baker City, Oregon, with a blown-out tire and no spare. My brand new car did not come with a spare! I called my insurance emergency assistance four times. I waited for my insurance company to call and get a tow truck for about three hours. A local towing company wanted to charge me $530.00 to tow my car about 20 miles to Les Schwab in Baker City. I mentioned to the insurance agent that I wanted my car towed to Les Schwab so I could get a new tire. The insurance agent called Les Schwab and I spoke with Jake at the counter. Les Schwab came out with a new tire, changed it and we were back driving in about 30 minutes. I went back to the store and bought a spare. Thank you Les Schwab, you saved our day. Too bad the other businesses I dealt with on Saturday did not have your ethics for putting customers first. Thanks again for being there for us. You will be the first I call next time I need a tire changed, and I will recommend to my insurance company they need to put you on their call list. Penny M., Baker City, OR
The time to find out if your new or used car is going to come equipped with a spare is before you sign on the dotted line. Don't rely on the sales staff to volunteer the news. It can be difficult to tell which models come with a spare and which don't, since some trim levels will, but not all. Be sure by asking the sales rep directly. (And if you've recently bought a newer model car, be sure to check whether it has a spare, so you're prepared with an alternative in case of a flat.)
Why Aren't Some New Cars Coming With Spare Tires?
A bunch of factors are in play.
- Efforts to improve fuel efficiency. Removing the spare can reduce a vehicle's weight by about 30 to 50 pounds, once you include the jack and wrench. It can also improve aerodynamics by reducing air drag from spare tire compartments that poke below the undercarriages of vehicles. These two factors can improve miles per gallon performance and help carmakers meet strict EPA standards for their full fleets, an attractive option for both car companies and energy-conscious drivers.
- Need for more space in smaller vehicles. A spare can take up significant room in compacts, sports cars and small sedans. There can be a trade-off between comfort and the space in small cars.
- Lack of storage space, especially in hybrids, diesels and electric vehicles. Batteries and emissions equipment for such vehicles sometimes now take up space where the spare used to go.
- Reduced manufacturing costs. Yep, a carmaker can save several hundred dollars by foregoing the spare in new cars.
What Are Alternatives to a Spare Tire? Are They Any Good?
Some new cars are coming from the factory equipped with tires or inflator kits that claim to make the spare tire unnecessary. There are upsides and downsides to all.
Run-flat tires are designed to allow driving for a limited distance after losing air from a typical puncture. They are built with either a reinforced sidewall or an internal support ring to carry the vehicle's weight if the tire tread gets pierced. (The sidewall is the curbside face of the tire.)
Run-flats are made to travel from 10 to 50 miles under 50 mph when deflated, so you can get somewhere for service. Run-flats may also offer better control than standard tires when there's a tire failure involving complete loss of air.
Downsides: Driving on a run-flat for even the shortest of distances will ruin the tire. It will have to be replaced. Plus, if you're somewhere remote and get a flat, you may not be within range of the next tire repair shop.
Self-sealing tires have a lining coated with special sealant inside the tire. When an object on the road pierces the tread, the sealant material "surrounds" the hole. Then when a nail or other debris is removed, the sealant fills the full area.
Downsides: The self-sealing tire won't work if a puncture is more than about a quarter of an inch in diameter. They also don't work for sidewall holes, so if an object goes through the tread to the sidewall you're going to have a dead flat and won't be going anywhere.
Inflator kits are a growing - but less-than-ideal - substitute to the spare tire. New autos with standard tires sometimes come with an aerosol seal kit. Such products offer a very temporary fix for minor tread punctures so you can get to a nearby tire store or service station for repairs.
Some are as simple as $10 canned products that plug small puncture holes by spraying sealant into the flat via the air-inflation valve and inflating the tire just a bit. Other tire-sealant kits include a small air cartridge and a replaceable container of sealant at a cost between $20 to $80.
Downsides: Tire sealant kits only work on small holes in the tread, and they don't work at all for slits or holes in the sidewall.
Sealants also leave grime inside the tire that can affect your TPMS (tire pressure monitoring system), the safety equipment that alerts you if you've lost air in a tire. Any time you use a sealant you'll need to have the TPMS sensors in your tires cleaned. And sealants can easily damage these sensors. You're looking at a cost of $45 to $100 per tire if they need to be replaced.
When Is It OK to Go Without a Spare Tire? And Not?
If you're buying a new car, here are five tips for deciding whether to get a model with no spare, based on where you live, what type of driving you're doing, cost, safety and convenience.
- The freeway shoulder can be a dangerous place to change a tire. If you live in an urban area with 24-hour towing, and you're doing mostly daytime driving, you may be good with no spare. Just be sure you have AAA towing service ($69 a year for the basic package), roadside assistance coverage included in your auto insurance policy, or one of the new, on-demand services. Without it, a standard tow (around 5 miles) will cost you an average $109, according to Angie's List.
- Decide up front if you're willing to go spare-less for the life of your vehicle. If you find yourself regretting your decision later, you'll pay more for an aftermarket tire, jack and lug wrench (typically $150 to $300) than you do when the kit comes as original equipment on a new car. Plus, there may not be a space to safely carry them in your vehicle if you bought a spare-less auto model.
- If you take a lot of road trips, routinely drive in places with long distances between service stations, or travel a lot on rougher roads, you need a spare tire. Getting a flat in rural areas means you could be a hundred miles or more to the nearest repair shop. If it's after business hours, you could be looking at being marooned for hours, paying for a hotel for a night (or more if it's a weekend), leaving a vehicle loaded with gear or belongings on the side of the road, and paying a hefty towing fee over a long stretch of highway.
I lease my 2013 Hyundai. I came out after work to a flat tire. I opened my trunk and imagine my surprise when there was no spare tire. I called Les Schwab and they said they had a guy in the neighborhood and he would be right there. He came and put air in my tire and followed me to the nearest store. It was after closing, but they kept the bays open for me. They removed the screw from my tire and sent me on my way with no charge. Who does that? I am a fan and tell everyone I know! Peggy P., Sacramento, CA
Get a spare tire if you travel with small kids, especially if you're taking occasional road trips. Getting stranded with a flat and no spare can mean several hours of waiting for a tow, even in an urban area. This is sure to be stressful for parents and possibly unsafe for tots, especially if it's a really hot or frigid day.
If you have medical needs that need daily attention, better have a spare.
Flat tires can be a major, costly hassle - or simply a slight inconvenience. Especially in the West, where distances between tire service can be long and lonely, a spare tire is the most cost-effective insurance that you won't get stuck by the side of the road.
Does Hitting a Pothole Damage My Tires?
Hitting a pothole can puncture your tire or bend or crack your wheel. It can damage your tire's sidewall or belts. Even a smallish impact may knock your vehicle out of alignment.
The potential problems can go beyond your wheel-tire assembly. A pothole strike can result in broken shocks or struts, dents or cracks in the body, or harm to other suspension or engine parts.
It's important to get your vehicle checked after a harsh encounter with a pothole ? or any debris ? on the road. Some damage will be obvious, like a flat tire, while some may not be visible. Get your car in for a look-see right away, especially if you notice these indicators:
- A tire looks low. This could be a slow leak from a bent rim.
- You see a bulge on the tire sidewall, a sign the tightly packed cords of steel belts and nylon in the tread have separated.
- Your car pulls to the left or right when you're driving straight. Your wheels are probably out of alignment.
- You feel a vibration in the steering, seat or floor, a symptom of imbalanced tires.
- You hear a new noise when underway. Something may be rubbing on your suspension.
- A dashboard warning light comes on.
Here's some background on Road Enemy No. 1: the common types of damage, what repairs may cost and whether your auto insurance will pay for them, and how to avoid these expensive hazards.
Yes, There Are LOTS of Potholes
It's not your imagination. American drivers are putting up with a lot of potholes, and the price tag is steep.
A 2016 AAA study found potholes cost U.S. drivers an estimated $3 billion in repairs annually. Over the last five years, an estimated 16 million drivers have sustained such damage to their tires, wheels or suspension.
Why such high numbers? The nation's blacktop is aging. There's been a lot of deferred maintenance so much-needed repairs are backlogged. Extreme cold, heat, rain and excess water under roadways also mean more cracks in the road, which is how potholes are born.
How Badly Can Potholes Damage My Vehicle?
Unless the hole is relatively large or you're going really fast, the pothole strike probably won't puncture your tire, or damage part of your suspension or engine. But bent wheel rims, internal tire damage, alignment problems, body damage, and shocks and struts issues are common.
When you take your vehicle to a tire technician or mechanic following a pothole impact, ask him/her to check for:
- Wheels/steering knocked out of alignment.
- Damage to the tire's steel belts.
- Intact tire balancing weights.
- Bent or cracked wheel rim.
- Damage to the engine or exhaust system.
- Damage to shocks and struts.
- Other broken suspension components.
What Will the Repairs Cost Me?
Auto repair costs due to potholes can range anywhere from $50 to $500. American drivers report paying $300, on average, to fix pothole-related vehicle damage, according to AAA.
If a tire is damaged, check your tire warranty. If it's a good one, repairs or replacement from road impacts may be free.
If your tire isn't covered by a good warranty and it's damaged beyond repair, a new tire will cost you on average $128 ($155 for light truck tires) in 2017 prices. Bent wheels can often be fixed but replacing a single rim may cost you between $75 and $500, depending on how fancy it is and whether welding, repainting or refinishing is needed.
Does Auto Insurance Cover Damage from Potholes?
If you don't have a strong tire warranty or if the impact caused damage to other parts of the vehicle, check your insurance policy. If you have collision coverage, auto insurance may cover the cost of repairs, but there's usually a high deductible to meet. Because such an incident is considered a collision by your insurer, reporting it may jack up your insurance rate. It may turn out that just paying for repairs will be cheaper than filing a claim.
First, get a repair estimate. Then, talk to your insurance agent about whether it's smarter to self-pay or file a claim. It depends on your driving record and your insurer.
Check Your Car Dealer Service Warranty
Before shelling out the dough for repairs, also read your vehicle's service warranty. Some car dealers offer tire/wheel protection plans as options on long-term warranties, in some states and on some vehicles. Such plans may cover damage to tires and wheels caused by potholes, nails, glass and other road hazards, dent repair, windshield fixes, labor and even towing charges.
Tips for Avoiding Hazards
There's an app for this. Really.
Waze provides driving directions along with real-time alerts on road hazards (including potholes), slowdowns, construction zones and accidents.
In the future, connected car and self-driving car technology will probably assign the work of avoiding potholes to your onboard computer. Technology to detect potholes in real time and share out the info to help motorists avoid them and help authorities prioritize repairs is well along.
In the meantime, here are the best ways to prevent pothole damage and stay safe.
Always drive on tires that are properly inflated and in good condition. This will give you the best chance of absorbing the impact safely.
Drive defensively. Slow down when you're on an unfamiliar or rough road, and avoid distracted driving. Be alert to what's ahead, and make sure you keep enough distance between you and the vehicle in front so you can see what's coming.
Be cautious about leaving your lane. Swerving to avoid a pothole is one thing on a country lane, but it's another at highway speed. Use good judgment and always be conscious of traffic around you. Recognize that though you miss the first pothole, there may be another awaiting. It may be safer to just brace yourself and drive straight through the hole.
When you can't avoid a pothole, take your foot off the gas and straighten your steering wheel. Don't brake. This will allow you to maintain the most control during the impact.
Guide to Tire Pressure Monitoring Systems
Notice to our customers: Important changes affecting vehicles equipped with Tire Pressure Monitoring Systems have been put into place.
What is a Tire Pressure Monitoring System?
TPMS stands for Tire Pressure Monitoring System. It is a feature on many late model vehicles that monitors tire pressure and warns the driver, with a light on the dash, if one or more of the tires' pressure falls 25% below the original equipment manufacturer's recommended tire pressure.
See the questions below to learn more about TPMS, and how to check if your vehicle is equipped with TPMS.
Why does TPMS exist?
As a result of tire-related safety concerns, Congress passed the TREAD Act in 2000. The TREAD Act requires vehicle manufacturers to install TPMS in new vehicles with a gross vehicle weight of 10,000 pounds or less.
What vehicles have it?
Passenger cars, SUVs, and light trucks. TPMS has been progressively introduced in new vehicles since 2005. Refer to your owner's manual for more information.
How do I check to see if my vehicle has it?
When you start your vehicle, look at the dash for the TPMS warning lamp. If you see the warning lamp light up momentarily, your vehicle is equipped with TPMS.
What does it mean when the warning lamp is on?
The warning lamp should light up briefly when the vehicle is started. But if the light stays on, that means tire pressure is low in one or more of the tires, or the system is not able to read the sensors. In this case, you should have your tire air pressure checked. We provide this service for free at all of our Les Schwab locations.
What kind of maintenance is required on my TPMS?
Replacement or relocation of a TPMS sensor, or sometimes even just inflating a tire may cause the TPMS to get out of whack. Generally, recalibration is easy to perform: we provide this service to customers free at all Les Schwab Tire Centers.
Does this mean I don't need to check my tire pressure?
Regardless of TPMS, we recommend tire pressure checks every 30 days. Properly maintained tire pressure decreases tire wear and improves vehicle safety, handling, braking and fuel mileage. Come in anytime for a free air check.
Use our Store Locator to find the Les Schwab nearest you.
How Do I Check My Tire Pressure?
Low tire pressure can be an expensive proposition, costing you hundreds of dollars a year in lost fuel economy and prematurely worn tires. Add to that, decreased handling and an increased risk in tire failure, and it's easy to understand why maintaining proper tire pressure is so important. Tires naturally lose 1 to 2 pounds of pressure a month. Cool temperatures cause even more pressure loss. So it's important to check your vehicle's tire pressure regularly.
We recommend you check your tire pressure at least once a month or twice a month in the winter.
Using an Air Pressure Gauge
Here's how you go about it with an air pressure gauge, can be found at most any auto parts store.
First, look in the owner's manual or on the inside placard of the driver's side door for the standard cold tire inflation pressure. This number is the PSI, or Pounds Per Square Inch, you will inflate your tires to, as suggested by the car's manufacturer.
Next, unscrew the cap from the valve stem on the tire.
Now, press the air pressure gauge onto the valve stem and record the reading given. If there's a hissing sound, try re-seating the gauge for a tighter fit and more accurate reading. Note that if the reading on all four tires is the same as the manual's specifications, you're done. If any of the tires have inadequate pressure, add air until they're properly filled. Make sure you put in the correct amount by rechecking the pressure in each tire after refilling.
Finally, replace the valve stem cap to protect the valve mechanism from dirt and moisture.
While you're at it, check the pressure on your spare tire, as well. You never know when you might need it.
Follow along as we show you how in this video:
Or you can simply stop by your nearest Les Schwab Tire Center, where we not only check tire pressure for you but also adjust it, if necessary. Free of charge.
Have any questions about tire pressure? One of our experts will be happy to help.
How Do I Know if My Tires Need to be Balanced?
Tire balancing is a tune-up for your wheel-tire set. It makes sure that weight is evenly distributed around the entire circumference of the unit. The common symptoms of out-of-balance tires are uneven and faster tread wear, poor fuel economy, and vibration in the steering wheel, the floorboard or the seat that gets worse at faster speeds.
When all areas of the wheel-tire unit are as equal in weight as possible, the tire will roll smoothly. This helps it wear evenly, for longest life. Balancing also contributes to ride comfort: Imbalanced tires will wobble or hop up and down, which causes vibration. If a front tire isn't properly balanced you'll likely feel vibration in the steering wheel. If the problem is in the rear the tremor will be noticeable in the seat or floor.
Imbalanced tires are easily corrected, but the work is precise. It's done by attaching small weights, just fractions of ounces, to the wheel.
How Do Wheels Get Out of Balance?
Everyday wear on tires will contribute to imbalance. Normal manufacturing imperfections are also a cause: Tires and wheels don't have precisely equal weight distribution. They'll be slightly heavier in some spots.
Just half an ounce in weight difference is enough to cause a vibration when you're driving.
How Tires Are Rebalanced
Rebalancing is done in a tire shop by putting the wheel-tire unit on a tire balancing machine that takes measurements to pinpoint lighter or heavier areas and making adjustments to account for these weight differences. The best time to get it done is when tires are being rotated, both for convenience and because you might have a tire out of balance on the rear of the vehicle and won't feel it until it is moved to the front.
Here's how it's done:
- A tire mounted on a wheel is attached to a tire balancing machine.
- The wheel is spun while vibration measurements are taken. This tells the tech if the weight is spread evenly, how much weight to add and where on the wheel to attach it.
- If an imbalance is found, the technician may be able to rebalance and adjust the weights (adding more). But sometimes it requires the tech to also move the tire on the wheel and then rebalance. This is because a heavy spot on the wheel and on the tire can sometimes line up together, causing a greater imbalance that needs to be corrected.
Balancing Versus Alignment
Though both should be part of regular auto maintenance, balancing isn't the same as getting an alignment. Alignment is about correcting the angles of the tires so they're properly positioned in relationship to each other and to the road. It gets the wheels all traveling in the same direction and makes sure the tires make contact with the ground as they should.
When to Get Tire Balancing Done:
- You feel vibration in the steering wheel, the floorboard or your seat.
- You get them rotated, generally every 5,000 miles.
- At the very least every two years, once yearly if you drive rough roads.
- You get a flat and repair a tire.
- You buy any new tire(s).
- A weight that used to be on the rim falls off.
- You notice uneven tire wear.
Vibration when underway could be caused by an imbalanced tire and wheel assembly or something else ? a bent wheel, a damaged tire (which won't be fixed by balancing), worn suspension parts or other aging components. If you feel a vibration, don't wait to get it diagnosed. You'll head off other problems - and enjoy a smoother ride - when your tires are well balanced.
How Do I Know When I Need New Tires?
The primary functions of tread are to divert water from beneath the tire, to improve traction and to avoid hydroplaning on wet roads. As tire tread wears down, it becomes less reliable. Find out when you need new tires in this video, or read about it below.
Tires become completely unsafe when they're worn down to 1/16 of an inch. Many people prefer to replace their tires even sooner, especially when driving in adverse weather conditions.
Check Your Tread Wear Bars
All tires sold in the United States today have what are called tread wear bars. These are small raised bars of rubber in the grooves of your tire. Look at the tread pattern and you'll see these bars running between the tread blocks. As your tires wear, these bars will become flush with the tire's tread. When this happens, it's time to replace the tires.
Do a Penny Test
An easy way to check the tread on your tires is to do the penny test. Take a penny and place Lincoln's head in one of the grooves of the tire tread. If you can see all of Lincoln's head, it's time to replace the tire.
If the penny goes in enough that the tire tread is at least as deep as Lincoln's forehead, your tires are generally considered safe and do not need replacing. Make sure when you're administering the penny test that you check all four of your tires.
While you're at it, check a few spots on each tire to look for any irregular tread wear. This could indicate a wheel misalignment, need for tire rotation or both. Talk to one of our tire experts if you think your tires are wearing unevenly.
How to Change a Tire
Changing a flat tire isn't rocket science, but there are some important things to know to make sure you get that spare on properly in order to make it safely to the tire shop. Follow along as we show you, step by step, how to do it in this Les Schwab Quick Tips video. We cover:
- What to do before you get tools out.
- How to find the proper jacking point on your vehicle.
- How much to loosen lug nuts before lifting the car.
- How to make sure the spare goes on correctly.
- The proper order for tightening lug nuts.
How to Change a Tire
- Safety first. Keep clear of passing traffic, make sure your car is in park, set your parking brake and turn on your hazard lights. If there's any doubt about whether you can stay out of harm's way, it's better to call roadside assistance.
- Check your owner's manual. It should have tire-changing instructions, including the location of the jacking point.
- Get your spare and tools out. They are usually stored in a compartment inside the trunk. There should also be instructions on how to use the jack.
- Be sure the jack is positioned properly. Make sure it's pointed the right way and placed in the proper jacking point on the vehicle.
- Loosen lug nuts about a one-quarter turn before jacking.
- Jack the vehicle up enough so the tire is not touching the ground.
- Remove the lug nuts, setting them somewhere where they won't roll away.
- Pull the flat tire off, placing it underneath your vehicle behind the jack or, if it's too wide to fit there, in another spot under the auto if possible. This is important in case the vehicle falls off the jack.
- Put the spare on, making sure the valve stem is facing you.
- Screw the lugs nuts back on by hand, finger tight.
- Lower the jack down until the tire contacts the road and is bearing some weight, but not all the way.
- Tighten the lug nuts in a star pattern, not a circle pattern, so the wheel gets seated snugly. This assures the wheel isn't askew, and doesn't then pop into the proper place while you're going down the road, loosening some of the bolts and causing wobbling or worse ? like the nuts breaking and the wheel coming off.
- Lower the vehicle the rest of the way. You're ready to drive slowly to the closest tire shop to get your regular tire repaired or replaced.
Spares are meant to be driven on short distances and not at high speed. The speed rating of your spare tire may be lower than your normal tires'. Have a tire technician check the condition of your spare at the shop so it's ready next time you need it.
How to: Make Your Tires Last Longer
Do you like plunking down your hard-earned money on a new set of tires? Unless you're a true enthusiast, probably not. If you want to extend the life of your tires, improve your car's ride, and have a safer drive, follow these four quick tips.
1. Check your tire air pressure monthly
Take the easiest step to extend tire life: Maintain the correct air pressure. The wrong air pressure can cause sluggish handling, increase stopping distance, increase wear and tear and heighten the risk of a blowout. Tire pressure changes:
- Every month. Tires can lose about a pound per square inch (PSI) of pressure monthly.
- In winter, when colder temperatures can lower air pressure.
- In summer, when warm weather increases tire air pressure.
Check tire pressure monthly
This isn't just about money, either. Proper tire pressure is important for safety. A National Highway Transportation Safety Administration Crash Causation Survey found tire issues in one out of 11 crashes. (Source: http://www-nrd.nhtsa.dot.gov/Pubs/811617.pdf [PDF]) Correct air pressure improves fuel efficiency. Underinflated tires mean you're getting fewer miles to the gallon and paying more for gas than you need to. You can improve your gas mileage by up to 3.3 percent by keeping your tires inflated to the proper pressure. (See more gas mileage tips at http://www.fueleconomy.gov/feg/drive.shtml.) The right tire pressure is an easy "win." Go check!
2. Get your tires rotated every 5,000 miles
In most cars, only one or two wheels "drive" the car at a time. That can cause uneven tire wear. For example, on front-wheel drive vehicles, front tires wear faster. On rear-wheel drive vehicles, it's the back tires. Even all-wheel drive vehicles can see uneven wear, as most shift the drive from one wheel to another. A technician rotates your tires by moving them to different wheel positions on the vehicle.That gives tires on drive wheels a rest and evens out wear. Rotation makes tires last longer. Do it every 5,000 miles.
3. Have wheels balanced
Tire rotation is a great time to get your wheels balanced, as well. Every tire and wheel has a heavy spot in it. None is perfect, even when brand new. The difference is tiny, measured in one-quarter to one-half ounces. But that small difference can cause vibration and uneven tire wear. Your mechanic can balance each wheel using a specialized machine and small weights. As the tire wears, he may need to move or change that weight. It's a fast, easy process that costs a lot less than a new tire! Make sure you get your tires' balance checked and adjusted during rotation.
Get wheels balanced
4. Check your alignment twice a year
Misalignment may make your tires toed-in ("pigeon-toed") or toed-out ("duck-footed").
Toed-in and toed-out misalignment
If your car actively pulls or drifts right or left, or the steering wheel vibrates or shakes, your car may have an alignment problem. But your car or truck could be driving fine and still be out of alignment. When you bump up against a parking lot barrier, hit a pothole, or hit the curb, something has to give, and it's often your alignment. The smallest misalignment can reduce fuel efficiency, and increase tread wear. Your mechanic can adjust your car's alignment. Take your car in for a check every six months. Or whenever you think something is wrong. A little maintenance can help save a lot of money. Follow these easy, inexpensive tire maintenance tips and you can increase tire life. You'll also improve gas mileage, extend the life of your car, and make your drive a safer one. You can start right now: Check your tire pressure. See? That wasn't hard, and you just saved yourself some money.
How to: Put on Snow Chains and Drive Safely
First the bad news: if you travel to the mountains or snowy areas regularly, sooner or later you're going to have to use tire chains.
Now the good news: these are not your grandpa's chains. Quick-fit chains are MUCH simpler to put on and take off.
Do these two things before you need to use your snow chains.
The driving conditions when you need chains are likely to be nasty. Snow is coming down, passing traffic is spraying slush, dirty water is dripping off your wheel wells, the road is slick and it may be dark. Don't make this the first time you put on your chains. Practice once BEFORE you travel. Make sure new chains are the right size by pre-fitting them on your tires somewhere dry, like your driveway or garage.
Second, put together a simple winter road trip safety kit with spare waterproof layers and items that will make your winter driving more safe and comfortable. In winter, always carry it in your car with your chains.
Want a quick how-to on putting on quick-fit snow chains? Here are a video, step-by-step instructions and driving safety tips.
When and how to install your tire chains
Snow chains are made for use on packed snow and slush. They shouldn't be used for just driving on wet pavement, which makes them likely to break. Using them a lot on ice will also make them wear quickly, though sometimes it's necessary to chain up to get past an icy patch of road.
Here's how to put snow chains on.
1. Pull off the road as far as possible on a safe shoulder. Flip on your hazard lights. Put on your slicker, gloves, hat, headlamp and waterproof pants from your winter road trip kit and grab your chains bag.
2. Ideally chains are installed on all four tires. Some people use them on only two. Look in your owner's manual under snow chains or tire chains for what your vehicle manufacturer recommends and follow that advice. If you're using only two, the chains should go on the drive wheels. Typically, chains go on the two front tires for four-wheel drive and front-wheel drive vehicles, and on the back for rear-wheel drives.
3. Kneel or sit by the first tire on the tarp or cardboard from your kit. Unroll the chain, making sure the hook ends are facing the ground.
4. Push the yellow end of the chains behind and around the tire. Pull the two ends over the top of the tire and fasten them.
5. Grab the chains on both sides of the tire and pull them together toward the center of the tire.
6. Then hook the red fastener into one of the links, as snug as you can make it. Don't worry if there are some extra links.
7. Push the cable toward the back of the tire, positioning the chains loosely over the tread.
8. At the bottom of the tire is another red fastener and draw chain. Pull them toward you so there's no slack. Feed the red draw chain around the opening on the fastener. Pull it tight and lock a link into the notch on the fastener.
9. Feed the rubber end of the draw chain through the red rings. Depending on tire size, you may only be able to get it through one of the two rings, but try to get it through both. Stretch the rubber end tightly and hook it onto a link on the side chain.
10. Repeat this entire process on the other tire(s).
11. You want the chains tight against the tire tread. So drive forward about 15 feet and stop. The chain will have centered itself creating some slack. Retighten the draw chain on each tire. Then you're ready to drive. Grab your towel from your road kit to sit on so you keep your seat dry.
12. While driving, if you hear any indication that the chain may be broken and it's hitting your car, STOP as soon as safely possible. Chains that are flapping can wrap around a strut or shock component causing big damage to your vehicle. Listen for a loud sound of slapping, or metal on metal.
13. As soon as you're through the snow zone and have a safe place to pull off, stop, put on your hazard lights and remove the chains. Take off your wet outer layers and throw them in your road kit. Remember: DON'T drive for any distance on bare pavement.
How to drive with snow chains on
- Be sure to keep it at no more than 30 mph or you can damage not just your chains but your vehicle.
- Don't lock your wheels by braking suddenly.
- Start slowly, to avoid spinning.
- When parking, give yourself extra space so you don't break your chains by hitting a curb.
When you're back home
Because they're steel, tire chains will rust if they're stored wet. Lay them out to dry first.
Also check them for wear, especially if you've driven them on asphalt for any distance. Look for flat spots, and replace the chains if you find some.
Some stores that sell tire chains will give you a full refund at the end of the winter if you don't use them. Check to see if this is offered before you buy.
Want more tips on winter road safety? See 19 Winter Driving Resources You Can't Do Without.
Are Nitrogen-filled Tires Worth the Cost?
The main benefit of nitrogen-filled tires is that the loss of tire pressure is slower, because the gas in the tire escapes more slowly than air does. With more stable tire pressure, the thinking goes, you'll get better gas mileage and get full tire life since you're always rolling on fully inflated tires.
Claims are also made that nitrogen in tires prevents tire "rot" by limiting the moisture that naturally occurs inside tires and heads off corrosion of the wheel that can be caused by contact with moisture.
These claims are overstated. The advantages of tires filled with nitrogen, instead of plain ol' air, aren't big enough to justify the price tag or the inconvenience. On new car tires, the cost can range from $70 to as much as $179. On existing tires, you'll pay up to $30 per tire for service to drain air and refill with N2. Refills will run you $5 to $7 per tire, which you can expect to do less often than with air-filled tires. But you'll still need topping off every two or three months.
The Science of Putting Nitrogen in Tires
Small amounts of air naturally leak out of tires over time, especially when tires are subject to large temperature swings. This is because the walls of tires are slightly porous. When a tire gets hot the air inside it expands. The added pressure pushes minute quantities of air out through the pores, so you occasionally have to get your air topped off even if your tire doesn't have a hole.
Promoters of nitrogen tires point out they don't lose tire pressure as fast as air-filled tires. Since nitrogen molecules are bigger than normal air molecules, it is harder for them to leak out. This means a tire filled with nitrogen will maintain air pressure longer. Therefore, they say, you'll roll on tires that are always properly inflated, resulting in better fuel economy and longer tire life.
A normal tire filled with regular air loses an average 1 to 2 PSI (pounds per square inch) per month. It's true that there is a slower loss from nitrogen-filled tires. But this improvement is slight ? only about 1.3 PSI less over the course of an entire year, according to Consumer Reports. It's not enough to make a true difference in gas mileage or tire wear for people driving passenger vehicles.
This is partly because air is already made up of 78 percent nitrogen and just under 21 percent oxygen, with the rest a mix of water vapor, carbon dioxide and other gases. When tires are filled from a nitrogen air pump this ups the percentage of N2 to between 93 and 95 percent. It's never 100 percent.
Bottom line: Nitrogen will slow the amount of tire inflation loss to about one-third of what you'll experience with air. This means instead of losing one to two PSI per month, you'll lose 1/3 to 2/3 PSI per month. You'll still need to check and top off your air roughly every other month to stay within the ideal inflation range. And you'll spend far more than you'll save on gas and tire tread life. You're better off making simple tire maintenance part of your routine.
Go Ahead and Do It If:
- Your ride is a racecar. Nitrogen is used to fill tires for track cars, since it does offer the advantage of more consistent pressure.
- You're buying a new car with new tires that are being filled for the first time, you live close to a nitrogen filling tank, you have disposable income to spare and you never check your air pressure.
Nitrogen-filled Tires FAQ
There are more cons than pros for changing to N2 tires. For example, nitrogen filling tanks aren't easily accessible like air compressor tanks. You'll have to plan for refills in places that may be few and far between. This can cost you time and money. Here's all the info.
Q. How much will it cost to get nitrogen in my tires?
A. For fills of new tires, between $70 to about $175 at some outlets. Drains of air and refills with nitrogen on current tires, up to $30 per tire. Topping off can be between $5 and $7 per tire. If you want to keep your tires within 1 PSI of the ideal, you'll likely be topping off at least four times a year, probably more. This could be between $80 and $112 a year, and possibly a whole lot more. Compare this to paying nothing at all for regular air at a tire store, or around a buck per fill at a service station.
Q. Are they safe?
A. They're as safe as regular tires. Nitrogen isn't flammable and won't cause your tires to explode.
Q. Will I get better gas mileage?
A. You'll always get better fuel economy on properly inflated tires, whether they're filled with nitrogen or air. Under-inflated tires can lower gas mileage by about 0.2% for every 1 PSI drop in the average pressure of all tires. They'll also wear faster and be more prone to failure. The most economical way to make sure you're driving on well-inflated tires is to just check your tire pressure once a month or get it done by a technician (free at good tire stores).
Q. Will nitrogen prevent tire rot? Wheel rust?
A. Nitrogen is a "dry" gas compared to oxygen (which makes up about one-fifth of regular air). Nitrogen-filled tires don't generate as much moisture inside when tires expand from heat friction then contract when they cool.
However, rubber rot from moisture inside the tires of passenger vehicles is very unusual. Unless your tires are on a vehicle that's rarely driven, it's far more likely your tire tread will wear out before the small amount of moisture inside an air-filled tire degrades the rubber.
And today's alloy wheels are coated to prevent corrosion on steel parts?the belts, beads and sidewall buttressing?that may come into contact with water, so that's not a typical problem.
Q. Can nitrogen tires be filled with air?
A. Yes. It's unsafe to drive around on under-inflated tires, so don't hold off thinking you need to wait to top off until you can get to a filling tank. It's perfectly fine to add air and just get your next fill with nitrogen.
Q. Do they run cooler?
A. There's no significant difference between air-filled and nitrogen-filled tires in terms of running temperature.
Q. Where can I fill my tires?
A. Use this nitrogen dealer locator, but be aware that some filling stations require you to have purchased tires with them, or have a membership.
Q. Will I have a better ride?
A. There's no difference in handling or ride quality between tires filled with air or nitrogen, so long as they're kept properly inflated.
Q. How can I tell if I have nitrogen in my tires?
A. The tire valve stem will have a green plastic cap or a cap topped with a green indicator.
Q. How do tires get filled with nitrogen for the first time?
A. The tire is purged of air and filled with nitrogen several times using a machine, which takes out most of the oxygen along with any water.
Performance Tire Siping
What is Siping and how is it Done?
Siping is the process of cutting thin slits across the surface of a tire to improve traction for driving in snowy, wet or icy conditions. Siping can also help manage tire heat when the road is overly hot.
Siping is done by placing your tires (new or used) on a specially designed machine that rotates your tires while making small, nearly invisible 90-degree cuts in your tread. It's actually easier to tell if a tire is siped by the improvement in vehicle handling than by visual inspection.
Independent studies have found that siped tires help you stop your vehicle sooner. Find out how siping will improve your traction in the video, "Get better traction with tire siping," or read on below.
Should I Get My Tires Siped?
Tire siping improves traction and braking, makes for a smoother ride, and prolongs tire life. Siping won't reduce tire performance in any way. The tire tread retains its toughness due to the patented spiral cutting process. This leaves uncut areas known as tie bars intact, keeping your tread strong.
The surface of your tire is made up of many smaller surfaces called tread blocks. These surfaces are especially important when it comes to icy or wet road conditions. Tread blocks get their gripping power from the numerous sharp surrounding edges. Siping provides even more of these gripping edges.
Research has shown the most effective braking power occurs immediately prior to losing traction. Siping extends the window allowed for maximum braking power, by giving the existing tread a helping hand.
Your tires have to absorb impacts from the road's surface. When that surface is more coarse or rough, your tires have even more work to do. Siping gives your tires micro-flexibility, resulting in a smoother ride. This in turn reduces the wear on your tire's carcass (the tread, bead, sidewall, shoulder, and ply) and lengthens tire life.
Longer Tire Life
Heat generation is a common cause of rapid tire wear and even tire failure. While this heat is a natural result of friction, too much can be a negative.
Siping reduces friction heat and its effect on your tire by allowing the tire to cool. The sipes act by isolating heat into small "corrals" and allowing air to pass between them, thereby dispersing the heat and naturally cooling the tire.
Why Don't My Tires Come Siped From the Manufacturer?
First, the siping process we use would be too expensive and time-consuming for manufacturers. Plus, typical factory siping leaves small, vacant gaps in the tire tread. The Les Schwab siping process creates gripping edges without gaps and without removing any rubber, allowing the individual sipes to support each other.
How do I know if I need new tires?
Signs that your tires are wearing out or may need replacing include uneven wear, a decline in vehicle handling performance or ride, poor gas mileage, vibration, reduced brake responsiveness, tread that looks slick, and a tire that's losing air faster than it should. Just stop by any Les Schwab for an honest opinion on the condition of your tires.
How often should I replace my tires?
It depends on many factors, including your driving style, the mileage rating for the tires, conditions on the roads you typically travel, weather, and more. Bring your vehicle in anytime for a free visual inspection on how your tires are doing.
What are the parts of a tire?
Having a basic understanding of tire parts and how your tires are constructed can be useful when it comes time to buy tires. Here are the key components.
What do the numbers on the Sidewall mean?
It's a good idea to understand what the codes and numbers on the side of your tire mean. Click below to learn about tire sidewall terms.
Tire Size Explained: Reading the Sidewall
Tire size can be confusing. Some numbers on the sidewall are listed in metric while others are in inches. Plus, the right size for your car, truck or trailer can differ depending on tire use and your driving habits.
You can see your original equipment tire size in your owner's manual. This is the sizing recommended by the vehicle manufacturer.
If you're interested in switching out your tires for a different look or performance need, a good place to start is to look at the codes on your existing tires' sidewall. Then have a tire professional help you determine a tire size range that will fit your vehicle and driving goals.
Here's an explainer on what all the sidewall numbers and letters mean.
Tire Size Meanings
A: TIRE TYPE The first letter in the code tells you what class of tire it is.
P stands for passenger vehicle tire. P-class tires include cars, SUVs, crossovers, minivans and smaller pickup trucks.
LT means light truck tire, designed for vehicles that are towing trailers or have ¾- and 1-ton load capacity.
ST stands for Special Trailer. These tire sizes are meant for trailers, including fifth wheels and other travel trailers, boat trailers and utility trailers.
If there's no letter before the first number, you have a metric tire most commonly referred to as European size. It's also measured in millimeters but may have different load capacity than a P or LT tire.
B: TIRE WIDTH The three-digit number following the letter is the tire's width (from side to side, looking at the tire head on) in millimeters. Also called the section width, this measurement is taken from outer sidewall to inner sidewall.
C: ASPECT RATIO The forward slash separates the tire width number from the two-digit aspect ratio. The bigger the aspect ratio, the higher/taller the tire's sidewall, or "profile" as it's sometimes called.
The aspect ratio is a percentage. It's the height of the sidewall measured from wheel rim to top of the tread, expressed as a percentage of tire width. In other words, it's sidewall height divided by tire width.
In this example, the aspect ratio is 65, meaning the sidewall is 65 percent as high as the tire is wide. To get the sidewall height, take the tire width of 215 mm and convert it to inches (8.46). Then multiply this by .65 and you get 5.5 inches, the sidewall height in inches.
D: CONSTRUCTION TYPE This single letter tells you about the internal construction of the tire.
R is for radial tires, the industry standard for most tires today. They have better road grip, lower rolling resistance for better gas mileage, ride comfort and durability than previous generations of tires. In a radial tire, the plies - layers of strong cords made of a blend of polyester, steel and fabric and coated with rubber - are laid perpendicular to the direction of travel.
D is for tires built with diagonal (crisscrossed) plies, called bias-constructed tires. They are also called conventional, x-ply, or cross-ply tires. Some motorcycle and trailer tires still use this internal construction.
Some run-flat tires are identified with an F followed by the type of internal construction.
E: WHEEL DIAMETER This two-digit number specifies wheel diameter in inches, how wide the wheel is across the center. It's the distance between the two bead seat areas (where a tire gets slotted and tightly sealed onto the wheel).
F: LOAD INDEX The two-digit or three-digit number that follows the gap specifies tire load index. The load index symbol indicates how much weight a tire can support, based on the following standard chart. In our example, the load index is 89, which indicates the tire has a load capacity of 1,279 pounds.
G: SPEED RATING The last letter is the speed rating, which tells you the top speed it's safe to travel at for a sustained amount of time. A tire with a higher speed rating can handle heat better and provide more control at faster speeds. The maximum operating speed of a vehicle is no more than the lowest speed rating of all tires mounted on the vehicle. (Of course, you should always abide by speed limits for safer driving.) Speed rating is usually, but not always, a single letter (see the chart).
LOAD INDEX LOAD (lbs) LOAD INDEX LOAD (lbs) LOAD INDEX LOAD (lbs) 65 639 94 1477 123 3417 66 661 95 1521 124 3527 67 677 96 1565 125 3638 68 694 97 1609 126 3748 69 716 98 1653 127 3858 70 739 99 1709 128 3968 71 761 100 1764 129 4079 72 783 101 1819 130 4189 73 805 102 1874 131 4299 74 827 103 1929 132 4409 75 853 104 1984 133 4541 76 882 105 2039 134 4674 77 908 106 2094 135 4806 78 937 107 2149 136 4938 79 963 108 2205 137 5071 80 992 109 2271 138 5203 81 1019 110 2337 139 5357 82 1047 111 2403 140 5512 83 1074 112 2469 141 5677 84 1102 113 2535 142 5842 85 1135 114 2601 143 6008 86 1168 115 2679 144 6173 87 1201 116 2756 145 6393 88 1235 117 2833 146 6614 89 1279 118 2910 147 6779 90 1323 119 2998 148 6944 91 1356 120 3086 149 7165 92 1389 121 3197 150 7385 93 1433 122 3307
SPEED SYMBOL SPEED (mph) A1 3 A2 6 A3 9 A4 12 A5 16 A6 19 A7 22 A8 25 B 31 C 37 D 40 E 43 F 50 G 56 J 62 K 68 L 75 M 81 N 87 P 93 Q 99 R 106 S 112 T 118 U 124 H 130 V 149 ZR* W 168 Y 186 (Y) Above 186
*For tires having a maximum speed capability above 149 mph, a ZR may appear in the size designation... above 186 mph, a ZR must appear in the size designation, including a Y speed symbol in brackets.
Buying New Wheels or Changing Your Tire Size?
A tire size calculator is a quick way to see whether the tire size you're considering will likely fit your car, SUV, sports car, light truck or crossover.
But remember that will give you just an estimate. It's important to stay within the sizing tolerances of your vehicle. Tires that are the wrong size could cause pull in the steering wheel, rub against the suspension or auto body, reduce clearance on hills or result in a stiffer or noisier ride than you expected.
If you're considering mounting a different tire size on your vehicle, check with a tire expert. Find out whether the tires and wheels you have your eye on are the right fit for your vehicle's suspension, gearing and bodywork. And ask how any differences in revolutions per mile, tire speed, load index and speed rating will affect your ride quality and vehicle performance.
See how new tires and rims will look on your car or truck using our Virtual Wheels simulator, available at any Les Schwab.