Tire Basics

We recommend the following steps be taken when you are storing tires:

1. Avoid storing a vehicle with weight on its tires for long periods of time, as it will cause flat spots. Ideally the vehicle should be placed on jack stands to take the weight off the tires.
2. Avoid storing the tires in direct sunlight.
3. Clean each tire from brake dust, dirt and grime before storing.
4. Do not apply tire dressings on the tires. Most of these products shine the tire temporarily, rob the tire of chemical agents that prevent drying of the rubber. If you have used shine products, wash your tires with soap and water and scrub well.
5. Avoid any moisture and remove as much air as practical if tires stored on the rim. Place each tire in an airtight plastic bag to help reduce oil evaporation and then cover the sealed bag with a Tire Tote.
6. When tires are stacked against each other, they should be stored with white wall or white letter tires with the colored side against each other (white-to-white and black-to-black). This prevents staining of the white rubber, if not kept in plastic bags.
7. Store tires in a cool, dry place preferably in a dry basement or climate-controlled workshop to avoid hot and cold temperatures, as well as seasonal precipitation and humidity.

These precautions and procedures will help slow the aging process of your tires when not in continual use on your vehicle.

What is Low Rolling Resistance?

Tires with low rolling resistance require less energy than standard tires to propel them, which increases fuel efficiency. The easier it is to roll the tires, the less heat is generated, and the less fuel needed to advance the vehicle.

How to reduce rolling resistance and improve fuel economy?

The easiest way to improve the rolling resistance of a tire is to increase the air pressure, however an over-inflated tire will wear faster in the center of the tire, have less traction, and will impact the ride comfort and handling of the vehicle. For this reason, tire engineers try to squeeze every bit of rolling resistance out of a tire by means other than increasing the air pressure.Reducing the mass of the tire by using less material, or by using materials that are lighter, can help reduce rolling resistance and improve fuel economy. Materials like silica added to the tread compound can reduce the amount of friction without sacrificing traction. Low rolling resistance tires can also be designed to have stiffer sidewalls which reduce the amount of heat generated by the tire, which means less energy consumed.

How much gasoline will I save with low rolling resistance tires?

Many factors go into fuel economy. The largest factor is your driving habits. If you are the type of driver that accelerates fast and brakes hard, or are in a lot of stop and go city traffic, you will use up a lot more fuel than a highway driver that accelerates and brakes smoothly and gently. All conditions being equal, the typical low rolling resistance tire should save somewhere between 1.0% and 4.0% per gallon compared to a traditional all-season that does not have low rolling resistance features.

What does this mean for me?

Low rolling resistance tires can save you money and reduce your carbon footprint without any compromise to safety or how long your tires last. Using the current (March 2017) average of $2.25/gallon, the typical driver of the average domestic sedan would save approx. $33/year by choosing LRR tires vs standard tires.* Over a three or four year life span for a set of tires, this can easily add up to the equivalent value of getting one tire free.

*Based on an estimated 24 mpg, 11.3K miles driven/year and 3% fuel economy savings.

A "P" listed in front of the tire size indicates that it is "P-metric" size. P-metric stands for passenger vehicle. Passenger vehicles are cars (for example sedans and coupes), minivans, or CUVs, but can also be trucks that do not carry extra heavy loads or run on gravel roads. If there is no letter in front of the size, then the tire is for passenger cars, and closely equivalent to p-metric. These tires have an internal construction and use materials designed to give a smooth ride, good handling on the highway, and to last a long time.

LT Tires have “LT” in front of the size. They are for heavy loads, towing and off-road durability. They are more expensive than p-metric tires. This is because LT tires have extra material in the sidewall and under the tread that protects the tire from damage. The cords in a LT tire are a larger gauge than P-metric tires so the tire can carry heavier loads. Very often LT tires will have an extra steel belt, a deeper tread and thicker rubber in the sidewall for more protection vs a p-metric tire. LT tires are usually 8-ply (Load Range D) or 10-ply (Load Range E). Passenger Tires usually have a 4-ply or 6-ply equivalent sidewall. The performance trade-offs of the added material in LT tires are harsher ride, less fuel efficiency, and less responsive handling.

Which type of tire is right for you depends on how you use the truck. P-metric tires are perfectly adequate for pick-up truck owners that rarely go off paved roads, carry heavy loads, or tow a trailer. Many half ton trucks come equipped from the factory with p-metric tires for this very reason. If you own a half ton pick-up truck or full-size SUV and rarely if ever carry a load or go off pavement, then a p-metric tire will be a better choice for your replacement tire. They will ride smoother, last longer, and be more fuel efficient than a LT rated tire in the same size.

If your truck, van or full size SUV comes from the factory rated for LT tires, it is best to replace the tires with LT tires. P-metric to LT is acceptable, but never replace original equipment LT tires with P-metric tires due to them having lower load capacity ratings at maximum air pressure.

If you drive your truck heavily loaded or pull heavy trailer loads frequently, you should consider replacing your p-metric tire with an LT tire. Tradespeople that have their truck or van loaded with tools, supplies and equipment often find that the stiffer LT tires means less sway, and therefore better loaded handling. Others may find that the ride is slightly harsher and not as comfortable as p-metric tires. This is one of the trade-offs you can expect when you replace a p-metric tire with a LT tire.

There are three basic types of tread patterns: Symmetrical, Directional, and Asymmetrical. Each tread pattern type incorporates design elements for optimal performance in specific conditions. It is important to know what type of tread style you have on your tires so you can ensure that they have been installed in the correct position, and that they are always correctly rotated during service intervals.

Symmetric Treads: These are the most common type of tread pattern for standard sedans and light trucks. These tires use continuous ribs or blocks across the entire surface of the tire. The pattern on each side of the tire is the exact same. The benefits are even wear and long tread life since there are multiple front-to-back, side-to-side or diagonal rotation options to keep all four tires wearing at the same rate.

Directional Treads: A directional tread pattern is designed to roll only in one direction. For this reason, the tires always have arrows molded on the sidewalls indicating the direction that the tire needs to be mounted. Lateral grooves on both sides of the tire point toward the center of the tire, creating a ‘v’ shape. These grooves very efficiently pump water through the tread so the tire can maintain contact with the road for wet traction and to resist hydroplaning even at high speeds. Another benefit of a directional tread pattern on high performance vehicles is that they give more of an on-center feel for improved high speed stability. The drawback of a directional tread pattern versus a symmetric tread pattern is that they typically wear faster, and are harder to rotate, as they can only be moved from front to back on the same side of the vehicle.

Asymmetric Treads: Tires with asymmetric treads carry markings on the sidewall that indicate the ‘inboard’ and ‘outboard’ so you know which way they need to be mounted. This type of tread pattern is primarily for ultra high performance summer tires on sports cars or high end luxury sedans.

Asymmetric treads have all the benefits of directional treads, but with an added benefit of having a tread pattern optimized for the inboard side of the tire, and a different tread pattern on the outboard side. This means the tread grooves can be aligned to best serve the function of the specific part of the tire. For example, very often an asymmetric tire has a solid outside shoulder for grip in extreme cornering. At high speeds the weight of the vehicle is pushed to the outside edge of the tire so more rubber in contact with the road surface is beneficial. To compensate for the closed outside shoulder, the inside shoulder of the tire will likely have twice as many grooves to allow for water evacuation.High performance vehicles driven at the high speeds can benefit from this type of tread pattern.

With just a little explanation it is easy to understand what the letters and numbers mean on your tire's sidewall. The numbers are indicators of the size, type, and performance of the tire.

1. Tire Type The letter "P" at the beginning of the "Tire Size" tells us the tire is a P-Metric tire, referring to tires made to certain standards within the United States, intended for Passenger vehicles. If a tire size has no letters at the beginning, this indicates a Euro metric tire. P-Metric and Euro-Metric tires may have different load capacities. The letters "LT," either at the beginning or at the end of the tire size indicate the tire was designed for light trucks. Vehicle manufacturers equip some light trucks with "LT" type tires. These tires generally require higher inflation pressures than passenger tires.
   
2. Tire Width is the width of the tire measured in millimeters from sidewall to sidewall. The first three-digit number in the tire size refers to the tire width. For instance, in a size P215/65 R15 tire, the width is 215 millimeters.
   
3. Aspect Ratio is the ratio of the height of the tire's cross-section to its width. The two-digit number after the slash mark in a tire size is the aspect ratio. For example, in a size P215/65 R15 tire, the 65 means that the height is equal to 65% of the tire's width. The bigger the aspect ratio, the bigger the tire's sidewall will be.
   
4. Construction. The letter "R" in a tire size stands for Radial, which means the layers run radially across the tire.
   
5. Wheel Diameter is the size of the wheel measured from one end to the other. It tells us the size of the wheel that the tire is intended to fit. A size P215/65 R15 tire is made for a wheel with a 15" diameter.
   
6. Load Index indicates the maximum load that the tire can support when properly inflated. You'll also find the maximum load on the tire sidewall, in both pounds and kilograms.
7. Speed Rating tells you the maximum speed capability of a tire. Often speed ratings are matched to the top speed capability of the vehicle. For example, a tire with an H-speed rating has a maximum speed capability of 130 mph or 210 km/h.
8. DOT Symbol: The letters "DOT" on the sidewall indicate that the tire complies with all applicable Federal Motor Vehicle Safety Standards in the United States.
9. Tire Identification Number: The series of letters and numbers following the letters "DOT." The TIN consists of up to 12 numbers and letters to identify the factory location and the week and year the tire was manufactured.
10. UTQG stands for Uniform Tire Quality Grading, a rating system developed by the U.S. Department of Transportation to show relative tread-wear, traction and temperature capabilities. Traction grades indicate the wet traction of a tire under a controlled test. A tire with an "AA" rating offers outstanding traction in wet conditions. Temperature grades indicate the ability of the tire to withstand and dissipate destructive heat. A tire with a A rating can withstand higher temperatures and operate at higher speeds than a B or C rated tire. Finally, Tread-wear grades are based on standardized government tests to help predict the expected tread-wear of a tire. For example, a tire with a tread-wear grade of 200 should last twice as long as a tire with a tread-wear grade of 100.

*Images Courtesy of Goodyeartires.com

Hydroplaning happens when tires cannot displace the water under the tread fast enough. The tires lose direct contact with the road and skid or slide across a thin layer of water. This creates a potentially dangerous situation as the driver momentarily loses the ability to steer, brake or otherwise control the vehicle.

Tires have grooves in the tread pattern to channel water from beneath the tire. Wide open, deep circumferential grooves are the most efficient at expelling water quickly. Another effective tread design are grooves that are like chevrons pointed in the direction of rotation. The V shape is very common on directional high performance tires. The grooves have a direct channel to the outside of even a wide tire, while still providing traction and performance on dry roads.

No matter what style of tread pattern, very worn tires means the grooves have less space to funnel water out from under the tread. For this reason, worn tires have a greater tendency to hydroplane, even in light rain conditions.

Here are some important tips for wet weather driving and to avoid hydroplaning:

• Keep your tires properly inflated
• Rotate and replace tires when necessary
• Slow down when roads are wet: the faster you drive, the harder it is for your tires to displace the water under the tread
• Avoid deep puddles and standing water if possible.
• Avoid driving in outer lanes where water tends to accumulate
• Turn off cruise control in the rain or in wet conditions
• Avoid braking, and steer in the direction of the slide when you feel the tires begin to lose contact with the road.

At some point or another, you may have experienced a tire blow-out , or maybe you've watched helplessly as the tire on another vehicle explodes and veers towards the side of the road. The term "blow-out" generally refers to a tire that bursts, losing air pressure. People often assume that this happens when there is too much air pressure pressing against the walls of a tire. This; however, is not usually the case. Tires typically blow-out when air pressure is low. The low air pressure in the tire causes the tire to flex more and heat up. Eventually the rubber overheats and loses its bond to the tire's internal structure. The tread can peel-off from the rest of the tire, or the rubber in the sidewall breaks open, causing an instantaneous loss of air.

You can help reduce the chance of a blowout by keeping your tires inflated to the recommended air pressure, however there is always the risk of puncture. A slow leak over time, which reduces air pressure can lead to a blow-out. You should also avoid putting more weight in your vehicle then your owner's manual recommends. Overloaded vehicles cause the tires to work too hard, generating more flex and heat build-up. The other thing to do is to avoid potholes and debris on the road that could damage the tire.

If you do experience a tire blow-out it is important to react appropriately. Most people instinctively want to hit the brakes and swerve immediately to get to the side of the road. That can be a deadly reaction that could lead to loss of vehicle control. The correct reaction when you hear the loud noise and feel the steering wheel lunge to the side during a tire blowout, is to take your foot off the accelerator and brake immediately, and to maintain the steering direction. This will help you re-gain control of the vehicle and to stay in your lane. Once you have regained control of the vehicle and have a sense of how the blown out tire is impacting the steering of the vehicle, you can begin to pull off to the side, and slowly apply the brakes when safe to stop clear of traffic.

There are several types of warranties that come with tires: Manufacture Defect Warranties and Mileage Warranties. All tires come with some basic Manufacture Defect Warranty. Here is some additional information to help you understand the various warranties, and how you need to proceed with a warranty claim:

• Manufacture Defect Warranty: All tires have some type of basic warranty against defects in the process of producing the tire. This includes workmanship or material defects for the life of the tire (down to 2/32 of tread). An out of round tire is typically an isolated case when one tire will not balance. This should be quickly detected once the tire is on the vehicle. The term of the manufacturer defect warranty varies by each manufacturer, and per tire style.

 

• Mileage Warranties: A mileage warranty is determined by the tire manufacturer based on the average number of miles expected for the tire. To process a successful mileage warranty you must be able to provide the following: Installation records with mileage, rotation records and mileage when tire is removed from the vehicle. The tires must be worn evenly and have 2/32 or less of tread remaining to submit for a mileage warranty. Your paperwork and tire(s) will be inspected and measured. Upon a successful, you will receive a pro-rated credit for the unused mileage of the warranty.

 

While there are a few novelty tires with color incorporated into the tread or sidewall of the tire, most tires are black. This is because a key ingredient that is added to the mix of natural and synthetic rubber is carbon black. Carbon black are tiny dust-like particles that act like a bonding agent for the other ingredients in the tire. Carbon black has the added feature of catching ultraviolet rays and absorbing the heat of the sun. This helps protect the tire against ozone and UV damage.

No other additive has been found to be as effective as carbon black at protecting the rubber and prolonging the life of tires.In the absence of carbon black, ozone and UV rays would attack the molecules and chemical bonds of the rubber, which over time causes the rubber to rot, and weaken.

After many years of exposure, the light absorption capabilities of carbon black are reduced, particularly in tires on vehicles that are driven infrequently and parked outside for long periods of time. Repeated use of some tire shine products can also dull the carbon black, as well. Chemical discoloration caused by tire shine and cleaners is superficial, and limited to only the very outer layer of rubber that has been treated. Over time, chemically damaged tire rubber will return to black if scrubbed with regular soap and water. Superficial rubber discoloration does not impact the function of the tire, or pose any sort of safety risk. Older, sun and ozone damaged tires however, should be inspected by a tire professional for deep cracks and internal damage to ensure they are road worthy.

To help consumers evaluate their tires, the U.S. National Highway Traffic Safety Administration (NHTSA) created the Uniform Tire Quality Grading System (UTQG). The UTQG makes it possible to compare tires based on a standardized rating of treadwear, traction, and temperature resistance. The grade for each of these can be found on the side of your tire. Winter tires and certain light truck tires are not graded.

Treadwear

The UTQG treadwear grade indicates how long your tire tread will last in relation to other tires. For instance, a tire with a grade of 400 should last twice as long as a tire with a grade of 200. It is important to remember that the treadwear number in the UTQG rating is a relative number only, and actual tire performance can differ greatly for many reasons, including driving style, climate, tire inflation and vehicle weight.

Traction

The UTQG traction grade rates the ability of your tire to stop on wet pavement. Traction performance is given one of the following grades, which you will find on the sidewall of your tire: AA, A, B, C.

Tires with an AA grade stop faster on wet pavement than those with a C grade. Note that the UTQG traction tests do not test tires for cornering, acceleration, driving at high speed or driving on dry roads. Tires are tested for straight ahead braking only.

Temperature

The UTQG temperature grade indicates the ability of your tire to dissipate the heat generated by driving. This is an important measure since over time, heat can cause damage to your tires. Temperature resistance is given one of the following grades, which you will find on the sidewall of your tire: A, B, or C. All tires sold in the United States must have at least a C rating.

The tires in UTQG tests were inflated properly and the vehicles were not overloaded. Excessive heat can be produced by under-inflation of your tires, driving at high speed, driving an overloaded vehicle, and certain road and weather conditions.