Tech Tips: Are Your Tires Out of Date?

A few months ago we wrote about the subject of RV tires “dating out.”  No, you don’t need to fear that you’ll come out some time and find your tires have fled the rims, run off with some beautiful female tires, and popped out for an ice cream. What we mean is this: RV tires often look good and have plenty of tread left long after their useful life.

It’s a perennial subject among RVers: How long should my tires last? RV tires are peculiar critters, mostly because of how they’re used. Tires on your passenger car are pressed into service nearly every day, perhaps on short errands or commuting back and forth to work. But RV tires are a different story. Some may sit for months at a time, doing nothing, then suddenly be rushed out on the highway, perhaps doing several thousand miles during a few weeks of vacation—and then—back to the barn until next time.

As we’ve said, a lot of RV tires can look like they have lots of tread life left in them, but at the same time, because of their irregular use and the deleterious effects of UV radiation, be beyond a safe service life. So when should you replace your RV tires?  That depends! The “depends” rides on a number of factors. Tires that sit for six months, doing nothing but holding up the weight of an RV, will not last nearly as long as an RV tire that’s out running around more frequently. Tires that spend more of their time in a warm, sunny location won’t last as long as tires shielded from sun exposure by the nasty cloudiness of other areas.

So what’s the bottom line? “Statistics indicate that the average life of an RV tire is five to seven years,” says the Recreational Vehicle Industry Association (RVIA).  How old are your RV tires?  Some have wondered, “Short of keeping a receipt for tire purchases, how am I supposed to know how old my tires are?  After all, they don’t celebrate birthdays, do they?” Ah, date codes to the rescue!

Government regulations require that each tire sold in the U.S. be stamped with a date code that can be unraveled to reveal when it was made. Since the year 2000, the last four digits of the “DOT code” reveal the information we’re looking for.  Of those digits, the first two indicate the week of manufacture, and the last two the year. In our photo, this tire was built in the 22nd week of 2004.

Tires manufactured before 2000 have a different code scheme. Here the last three digits are the key—the first two of those representing the week, and the last digit the year of the decade. Let’s hope you don’t run into a tire that old on your rig. Old code or new, you can be sure some wag will have probably mounted your tires so the date codes are on the inside of the rim. Seems like the codes are only stamped on one side, so you may be in for a bit of a crawl under the rig to find what you’re looking for. 

The Tire Industry Association (TIA), which represents American tire manufacturers, has a few thoughts for RVers. TIA’s senior technical consultant, Marvin Bozarth, says RV tires may last longer than the average suggested by the RVIA, but the key to safety is having your tires inspected. Bozarth says any time your rig is serviced, your tires should have at least a quick once-over. At the 10-year mark, a tire specialist should make a thorough check.

Looking for damage that should sideline a tire?  Sidewall cracking or weather cracking, says Goodyear Tire, is a normal expectation of sunlight and heat exposure. When the cracks exceed a depth of 2/32 of an inch, it’s time for new tires. The same is true if you should see the tire’s innards, such as tire piles or steel cords.

Tire manufacturers add chemicals and oils to their tire rubber to reduce wear from weather. The substances are forced to the tire surface by the act of rolling down the highway, hence, a tire that gets more use will last longer. Want to kill the positive effects of those added substances?  Then paint your tires or use tire dressings. These will prevent the additives from doing their work. We’ve said it before, we’ll say it again: Avoid tire dressings like the plague.

What about covering your tires when parked?  There are plenty of decorative (and not so decorative) tire covers sold to RVers. Industry insiders agree, however, that as nice as tire covers are for keeping the dirt off, unless the tire is in real darkness, it can still be damaged by light transfused through the tire cover, or getting onto the “back side” of the tire—the one under the rig. Wish we had some powerfully great suggestions on this situation. We can only picture RVers crawling under their rigs, swaddling their tires in heavy black plastic. My back hurts just thinking about it!

Russ and Tiña De Maris are authors of RV Boondocking Basics—A Guide to Living Without Hookups, which covers a full range of dry camping topics. Visit icanrv.com for more information.

Russ and Tiña De Maris