When sitting in your RV, your total contact with the earth is 2, 4, 6, or 8 tires depending on the size and type of your RV. When driving or towing your RV down the highway at 60 mph, those tires are absolutely critical to your safety. Knowing this, you have to take care of your tires. Knowing this also directly relates to the quality of the tires you buy.
There are several factors you need to consider when buying tires. Among the more common are cost, quality, brand, and size. One factor often not considered or simply overlooked is tire age—even for new tires—or the date the tires were actually manufactured.
How to Find the Age of Tires
It is easy to identify the date a tire was manufactured. Each tire must have a Tire Identification Number (mistakenly called the tire’s “serial number”) molded into the tire’s sidewall. A Tire Identification Number is not a unique identifier like a serial number that’s used to identify a specific item. The Tire Identification Number is a batch code and this same code is used on all the tires manufactured within any given week. The following week, the code is changed.
A Tire Identification Number starts with the letters, DOT, and is 10–12 characters long using both letters and numbers. You need to be concerned with the last three or four numbers as these are the date the tire was manufactured.
How to Read the Tire Identification Number
There are two different types of Tire Identification Numbers, one type for those tires manufactured since 2000 and one type for those made before 2000. Here, we will deal with the most current first.
Tires Manufactured Since 2000… show the manufacture date as the last four digits of the Tire Identification Number. The first two digits identify the week and the next two digits identify the year. Note that the “week” refers to what specific week during the year the tire was manufactured—e.g., the first week of the year would use the two numbers “01,” the fifteenth week of the year would use “15,” and the last week of the year would use “52.”
The last two digits identify the year. That is, if the tire was manufactured during 2002 the last two digits would be “02,” or tires produced during 2010 would use “10.” As shown here, this tire was manufactured during the 30th week of 2009.
Tires Manufactured Before 2000… show the manufacture date as the last three digits of the Tire Identification Number. Just like the tires this century, the first two digits identify the week of production. Therefore, the fifteenth week of the year would use “15.”
The last digit identifies the year within the decade. Prior to 2000, it was assumed that tires would not be in service and simply not last for ten years. For example, if you looked at an old tire and the last digit was a “3,” it was assumed the tire was manufactured during the last decade of
that century (sometime between Jan. 1, 1990 to Dec. 31, 1999). More specifically, it was manufactured during 1993. While the “3” could also mean 1983, with the assumption of tires lasting less than ten years, being that extra ten years older is not likely.
You can still find tires over ten years old and they will have the three-digit Tire Identification Number. Don’t use them.
Finding the Tire Identification Number
Tires will always have a Tire Identification Number branded onto one sidewall. If you see a Tire Identification Number that seems incomplete, you may need to look at the tire’s other sidewall to find the total Tire Identification Number.
Safety and the Age of Tires
One of the problems with RV tires is that they can be really old and still look good with lots of tread. This happens when people with RVs simply do not use the RV very much. Therefore, the tire wear is minimal and the tread looks good regardless of the age of the tires. Tire aging typically isn’t an issue with vehicles driven frequently since the tires wear out before they get old.
While there is no fixed “law” or regulation as to when a tire should be discarded, the rule of thumb is that any tire six-years-old should be replaced, regardless of the amount of tread on that tire.
Buying What You Want
I purchased a set of eight tires for my motorhome late in 2009. When I set the appointment, I asked the person to make sure the tires were fresh—that is, manufactured in 2009. He said that he always checked on this. When I showed up for the appointment, all the tires were good, the Tire Identification Number was checked, and all were manufactured in 2009.
When you get ready to purchase those tires, get what you want—you are not limited to only what they offer. Tire dealers can get fresh tires. Insist on it.