Aged Tires

 

Aged Tires

In the last year or so there has been a discussion regarding aged tires. Specifically, when you purchase new tires there is a potential that those tires may be several years old before you install them. Some experts argue that new tires degrad while they are sitting on the shelf. Apparently, several deaths have been allegedly linked to aged tires. I have also read a number of articles that suggest that the total life of a tire (from manufacture to removal) should not exceed 5 to 6 years. Does anyone have a policy regarding aged tires? Also, does anyone require their tire suppliers to provide tires that are less than (x) years old?

Anonymous (not verified)
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When manageing tires in the City of Winnipeg, the rule was no tires/casings older than 5 years were to be introduced into the Fleet and tires were removed at 7 years. The proviso is you are using first tier North American supplied tires (Michelin Group, Bridgestone/Firestone and Goodyear). Branding is important as it is one of the few surities on the technological and manufacturing expertise brought to the fore.

Anonymous (not verified)
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We are just moving forward with the final policy approval dealing with age for tires. here is some of our ground work to support such a policy  ....

Replacement Age for Tires                          

 

Recent TV advisory reports alerted the public of the dangers of aging tires.  They focused on the age of the tires as being a factor in tire failure. 

 

While age is a factor, the Rubber Manufacturers Association (RMA) states that there is not a specific chronological age at which tires should be removed from service.  There is no data that supports that tires be replaced at a specific age. RMA officials state that tire care is a greater factor in their safe operation than age alone. Proper maintenance, inflation and regular inspection of tread wear patterns and damage are the keys to good tire performance.  The RMA recommends that a tire professional be used to inspect the tires for condition and age.

 

Various segments of the vehicle industry contend that age is a factor (i.e., In 2006, Ford Motor Company started recommending that tires over six (6) years of age be replaced regardless of condition.).  These groups point out the many factors that influence the average life expectancy of a tire, including exposure to sunlight and ozone, sitting for extended periods of time, and the amount of weight on them. Tires aren't designed to stand in one place for long periods of time.  This can create flat spots and prevent them from rolling smoothly.  This may cause them to build up too much heat. Tires can age more quickly when they aren't used regularly.  These groups estimated life expectancy between five and seven years.

 

While age may not be the major factor in determining the replacement of tires, consumers are still being warned to look out for “aged” new tires.  These are new tires that stay on the rack for a long period before they are placed on a vehicle.  The US Department of Transportation now requires that every tire must have a four digit date code on the sidewall, indicating the date it was manufactured. This is a string of numbers and letters that begins with "DOT" and ends with a four (4) digit date code. The first two digits indicate the week and the last two digits indicate the year (e.g., “0604” reflects a tire that was manufactured during the 6th week of 2004).  New tires over six months of age should not be accepted.

 

Based on the RMA’s statement that condition is the primary factor in determining when to replace tires, tires should be replaced based on the vehicle’s manufacturer recommendations.  This information is normally noted in the vehicle owner’s manual. 

 

Tires on all vehicles and equipments be inspected annually by a tire professional regardless of age and replaced based on the condition and the environment that the equipment is normally used in. 

 

New tires with a greater than six month shelf life will not be installed on any Company vehicles/equipments.

 

 

STATEMENT OF RUBBER MANUFACTURERS ASSOCIATION

 

Tire Service Life for Passenger Car and Light Truck Tires

Tires are designed and built to provide many thousands of miles of excellent service but must be maintained properly. As explained below, the service life of a tire is affected by many factors that are independent of the chronological age of the tire.

 

Service Life is Not Determined by Chronological Age

Tires are composed of various materials, including rubber, having performance properties essential to the proper functioning of the tire. These component properties evolve over a combination of time, service and storage conditions. For each individual tire, this change is affected by many elements such as temperature, storage conditions, and conditions of use (e.g., load, speed, inflation pressure, impacts and road hazard injury) to which a tire is subjected throughout its life. Since service and storage conditions vary widely, accurately predicting the serviceable life of any specific tire based on simple calendar age is not possible. RMA is not aware of scientific or technical data that establishes or identifies a specific minimum or maximum service life for passenger and light truck tires. However, in some cases a tire or vehicle manufacturer may make a specific tire replacement recommendation regarding its products. If so, the consumer should consult the manufacturer with any questions with regard to following the recommendation. Further, any such recommendation should not be considered a minimum serviceable life for the tire.

 

The Consumer Plays A Primary Role in Tire Maintenance

The tire industry has long emphasized the consumers’ role in the regular care and maintenance of their tires. (Tire care and service manuals are available from RMA on its website, http://www.rma.org.) Tires should be removed from service for several reasons, including tread worn down to minimum depth, signs of damage (cuts, cracks, bulges, vibration, etc.) or signs of abuse (underinflation, overloading, etc). That is why it is recommended to have tires, including spares, inspected regularly. A monthly maintenance inspection, for which the consumer must be primarily responsible, should focus on proper inflation pressure, tread wear and tire damage. This monthly inspection should be supplemented by recurring rotation, balancing and alignment services. This inspection should occur whether or not the vehicle is equipped with a tire pressure monitoring system. Additionally, the condition of a tire should be assessed regularly to determine if there are any tactile or visual signs of damage that make replacement necessary.

 

Storage, Rotation, and Other Conditions That May Affect Tire Service Life

Tires should always be stored in a dry, cool, well-ventilated place. Avoid storing tires in areas that are exposed to wetness, petroleum or petroleum-based products, extreme temperatures, direct sunlight, and/or other sources of ozone, such as electric motors. Storage areas should also be clean and free of grease, gasoline or any corrosive chemicals which can deteriorate the rubber.

If a vehicle is fitted with a matching full-size spare tire (same size and type as other in-service tires) the consumer should follow the vehicle manufacturer’s recommendation for rotating the spare tire. When any spare tire is placed into service, its inflation pressure must be checked immediately.

Consumers are strongly encouraged to be aware not only of their tires’ visual condition but also of any change in dynamic performance such as increased air loss, noise or vibration. Such a change in performance could be an indication of an internal condition that might dictate removing the tires from service immediately to prevent a tire failure. In these cases, RMA recommends that consumers consult a tire service professional.

Adopted March 2006

 

Car Tires:  Appearances Can Be Deceiving by The Automotive Mileposts Staff

You might think the actual miles on a tire are the most important indicator of how long they will last, but that isn't really true. Most of the tires manufactured today will simply wear out due to normal use, and since people are driving more miles these days, the life expectancy of a tire can seem to be quite short when judged strictly by the amount of time in service. A worn out tire under these circumstances is normally evidenced by tread wear indicators built-in to the tread during the manufacturing process. These tread wear indicator bands "interrupt" the normal tread pattern, and indicate the tire needs to be replaced.

 

But what about a tire that doesn't have any external signs to warn it may be near the end of its useful life? For instance, one that has very few miles on it, based on its deep tread and minimal wear, but it's not known exactly how old the tire is. The age of a tire also plays an important role as to how safe it is. This is especially true for tires mounted on classic cars and RVs. These vehicles normally see much less use, and while the tires on them may be 10 years old or more, they could have as little as 4,000 miles on them.

 

The average miles driven in the United States per person has increased from 8,685 in 1969 to 14,500 in 2001, and tire safety and durability has also increased greatly during this time. These statistics minimize tire failure due to age, since most tires are still relatively new when the tread wears out on them from normal use. But tires do not last forever. Nor do they always have warning signs that indicate they are past their useful life.

 

There are many factors that influence the average life expectancy of a tire, including exposure to sunlight and ozone, sitting for extended periods of time, and the amount of weight on them. Tires weren't designed to stand in one place for long periods of time, they were designed to roll around on a regular basis. Subjecting tires to long periods of standing can create flat spots, which prevent them from rolling smoothly, and cause them to build up too much heat. And too much heat spells trouble for a tire.

 

In fact, tires can age more quickly when they aren't used regularly, which is a real concern for classic car owners. Placing the car on jack stands when it won't be in use might help the tires somewhat, but could place strain on body and frame structures that weren't designed to support the weight of the car for extended periods.

 

If you're lucky, your tires will exhibit signs of aging that are easy to spot: cracks in the sidewalls, or a vibration in the steering wheel or a roughness at certain speeds, but don't count on it. The experts we spoke to said the average life expectancy of a tire on a classic car is just five to seven years. Much depends on how the car will be used. If the car is strictly a show car, and won't be driven other than for short distances to or from a car show, you might be tempted to push the longer limits of life expectancy. But if the car is going to be driven at highway speeds, or for any distance at all, it's best to play it safe and replace the tires more frequently.

 

All tires made in recent years are date coded by government order, which makes it easy to determine how old they are. The United States Department of Transportation now requires that every tire must have a four digit date code on the sidewall, indicating the date it was manufactured. Look for a string of numbers and letters that begins with "DOT" to see the date code. The code will look something like "0604" which indicates the tire was manufactured during the 6th week of 2004. This number only appears on one side of the tire, so you might have to crawl under the car to get the date.

 

Tires can be seriously deteriorated on the inside, while having a normal appearance on the outside. Finding out that a tire is bad at 70 miles per hour is not an acceptable risk. If you have a collector car, second car, or RV that sees little use, check to see how old the tires are. If you can't tell with any certainty, replace them, even if they look brand new on the outside.

 

Consider the many replacement tire options available for your vehicle as well. If your car isn't going to be judged, why continue to pay top dollar for Michelin steel belted radials just because that's what came on the car new? If the car isn't going to be driven much, you're not likely to need something with a high mileage guarantee or warranty. The tires will be old and past their safe useful life before the tread even comes close to wearing out. For this reason alone, we recommend buying less expensive tires, since you don't need tires capable of high mileage. You also won't be as likely to defer tire replacement to a later date due to the cost involved.

 

For the greatest safety and least cost, buy name brand tires from a reputable dealer. Make sure they're mounted and balanced properly when installed, have your front end alignment checked, always maintain proper air pressure, and check air pressure regularly.

Anonymous (not verified)
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We require the following

  • No new tires accepted greater then 3 yrs old from date of mfg. This ensures we do not have old stock sitting.
  • Retreads not to be introduced greater than 6 yrs two retread maximum (large tires only)
  • 10 maximum lifecycle on any tire

Mechanics were trained how to read the DOT numbers on the tire and deny deliveries & take tires out of service.