By Russ and Tiña De Maris
A man goes into an RV dealership, interested in a seven year-old motorhome with 10,000 miles on the odometer. The tires on the rig have plenty of tread left on them, but on learning that they’re the original tires, he wonders about them being too old to be safe. The salesman tells the customer that worrying about the age of the tire is nothing more than buying into a myth. Should the customer walk away?
Tires on your RV are a critical issue: Blow a tire, lose control, maybe lose your life. Being concerned with tire safety is only right. So what about it? Does the age of a tire have any bearing on tire safety?
Absolutely, say tire and highway safety experts. Here’s why: Over time, a tire’s structural integrity really can degrade. When it happens, the tire can fail, leaving you in a bad situation. While government experts estimate that “only” about 400 fatalities per year can be attributed to tire failure, tell that to the loved ones of someone who died because of a catastrophic tire failure. Not withstanding, when a tire blows, the damage caused to the RV can cost plenty – ask us, we’ve been there.
Time is not the only factor in tire “aging.” The ambient temperature also plays a role. The warmer the climate, the faster the tire will age. Expose the tires to UV radiation, common in sunlight, and they’ll age faster. RV tires can be especially susceptible to rapid aging because they’re more prone to sitting still for longer periods of time. When a tire rolls down the highway, chemicals in the tire that help to preserve it are distributed. Parked and not used, those chemicals don’t get a chance to help with tire longevity.
Still tread left, but UV killed this tire It’s the latter issue that can really come to the fore with RV tires. A seven-year old RV with 10,000 miles on the clock translates to what? Driving an average of a little over 1,400 miles per year. Lots of tread left, yes, but is the tire safe? The dealer in the true-to-life scenario above says, ‘Quit worrying!’ Not so, says the National Highway Transportation Safety Administration (NHTSA). Speaking of tires on RVs or collector cars as an example, the agency notes, “In those instances, the structural integrity of the tire may be weakened – and potentially hazardous – even though the tire still has a great deal of remaining tread.”
Is there any way to tell if an older tire is still safe for use? There aren’t any industry-accepted standardized tests to tell. For the average consumer, looking at a tire won’t really tell you – even tire experts can’t really tell. While the NHTSA suggests having tires inspected once at they five-year mark, and every year thereafter, if even the experts aren’t sure, how can you be safe? And how do you know how old your tires are anyway?
Your tires’ “birthdates” can be determined by looking for the “DOT code.” Printed on a tire sidewall, the code begins with the letters DOT. The last four digits in that string of numbers are significant. The first two of the four digits are the week the tire was made, the last two digits represent the year. So a code ending in 2509 means the tire was made in the 25th week of 2009. You may have to look on the ‘axle side’ of the tire to find the DOT code – they don’t make it easy.
How old is too old? That’s the big – and controversial – question. Nobody really wants to stick their neck out and say what’s safe, and what’s not. Some tire manufacturers will tell you their tires should be good for ten years. But ten years under what conditions? Cold weather? Hot weather? Driven 50 miles a week? Standing still under your motorhome or travel trailer for months at a time?
A ‘rule of thumb’ adopted by some in the RV world says replace your tires when they hit six or seven years old. In parts of Europe and Asia, tire manufacturers recommend replacement of tires every five years. Why not in the U.S.? It’s a mystery – at least to the consumer.