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October 28, 2009
A New Debate
How Long Does a Truck Tire Last?
Recently, some car manufacturers have been warning their customers to be aware of older tires—tires that might be six or seven years old. Their main concern? That older tires might be dry and that their rubber is prone to crack and fail at high speed. The age of a light vehicle tire can be determined by the date of manufacture moulded onto the sidewall of the tire. It is part of the DOT (Department of Transportation) identification number.
Though there still is a lot to be proven concerning aging passenger tires, many truck owners and operators have become seriously worried that the same could happen with their truck tires. Is it possible?
Truck tires are not built like light-duty vehicle tires. They are designed for vehicles of more than 10,000 pounds GVW and are constructed of a single steel body ply and 3 or 4 steel belts under the tread. They are designed to go hundreds of thousands of miles on their original tread. They then can be retreaded more than once before being considered as “scrap.” And yet…
According to Peggy Fisher, president of Tire Stamp and participant in tire-related activities within the Technology and Maintenance Council (TMC) in Heavy Duty Trucking magazine, medium-duty and heavy-duty truck tires are designed to run 1 million miles (1.6 million kilometres) today. And since they can be retreaded several times, they could take up to 10 years or more to cover that much mileage.
Maintenance is the key
Tire maintenance begins with proper air pressure. According to the Bandag Bandagram magazine and Guy Walenga, director of engineering, commercial tire products and technologies at Bridgestone Americas, commercial truck tires should be professionally maintained with visual inspection and proper pressure. Actually, fleets have the responsibility to employ and train tire maintenance professional to inspect tires and maintain inflation pressure. In Heavy Duty Trucking, Walenga also added that the company he represents has documented casings with 1 million miles (1.6 million kilometres) or more that were retreaded and repaired multiple times while in service.
What can shorten the life of a good truck tire? According to the Heavy Duty Trucking article sent to us by TRIB (Tire Retread & Repair Information Bureau), improper repairs will shorten the life of a good truck tire. Improper repairs can often be seen in a puncture repair process. Bad repairs will let air or moisture penetrate the casing and cause corrosion within the body of the tire. Also, other than underinflation, some atmospheric conditions like exposure to UV radiation and ozone will take their toll on the rubber, but this takes time. Today’s tires include anti-oxidants and anti-ozonants to minimize exposure to air and sunlight. Still, storing truck tires out of direct sunlight is a recommended operation.
One of the most unusual recommendations found in the article is to avoid steam cleaning, which can be harmful to tires if the nozzle is concentrated on one spot for a certain time. The damage can be even more severe if the nozzle is kept too close to the sidewall for more than 45 seconds. Steam can cause blisters.
Final word
According to the Bandag report, scrap tire surveys are routinely conducted by tire manufacturers to confirm and analyze the reasons for tire removal from service. These surveys have determined that properly maintained, inflated, repaired, and retreaded commercial truck tires can safely and reliably be kept in service for 10 years or even more.
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