September 8, 2026 · 4 min read
Why RV tires age out before they wear out
A car tire covers enough kilometres that the tread wears down before the rubber gets old. An RV tire is the opposite. Most trailers and motorhomes in Alberta sit for months at a time, and even a busy season adds up to only a handful of trips. That leaves the tread looking fine while the rubber underneath quietly hardens, loses flexibility, and starts to crack.
Alberta is hard on rubber. The sun is strong at our elevation, the air is dry, and a tire can go from hot pavement on a summer afternoon to a frosty night in the mountains on the same trip. Winter storage adds months of freeze and thaw. All of that speeds up the aging that happens no matter how carefully you drive.
Every tire carries a DOT code on the sidewall. The last four digits give the week and year it was built, so a code ending in 2219 means the twenty-second week of 2019. A common guideline in the RV world is to replace trailer tires somewhere around the five to seven year mark, even with plenty of tread left. Check the guidance from your own tire maker, and remember that a tire that was already old when you bought the RV is still old.
Pressure: check it cold, and check it often
Underinflation is the biggest cause of RV tire blowouts. A soft tire flexes more, and flexing builds heat. On a long highway pull in July, a tire that is only a little low can get hot enough to come apart from the inside. Nothing looks wrong until it lets go.
Check pressure when the tires are cold, before you drive, ideally first thing in the morning. Use the pressure recommended for your RV's actual loaded weight. The number moulded on the sidewall is the maximum for that tire, not always the right target. Your RV's placard or the tire maker's load chart will tell you where you should be. Do not forget the spare, and do not forget the inside duals on a motorhome.
Alberta temperature swings move pressure around. A tire set correctly in a warm Calgary driveway can read noticeably lower after a cold night at a campground in the Rockies. Recheck each morning on a trip. A tire pressure monitoring system is worth considering, because it warns you about a slow leak or an overheating tire while you can still pull over safely.
Sun cracking and other things to look for
Run your hand and your eyes over the whole tire, including the inside sidewall you cannot see without crouching. Fine surface crazing is the first stage of sun damage. Cracks you can catch a fingernail in, cracks that follow the bead or the shoulder, and any bulge or wavy spot mean the tire is past its safe life. Any exposed cord means the tire comes off before the next trip.
Uneven tread wear tells its own story. Wear on both outer edges usually points to chronic underinflation. Wear on one edge of a trailer tire can mean a bent axle or an alignment problem that will chew through a new set just as fast. Check the valve stems too, since rubber stems crack with age and a leaking stem is a leaking tire.
While the RV is parked, cover the tires and keep them off bare dirt and long grass. Boards or levelling pads under each tire help. Inflate to the sidewall maximum before long storage and move the RV a little every few weeks if you can, so the same patch of rubber is not carrying all the weight. Skip solvent-based tire shine products, which dry out the rubber and make cracking worse.
When to replace, and when to bring it to Horton
Replace when the tire hits its age limit, when cracks are deep, when there is a bulge or cord showing, or when a tire keeps losing pressure with no puncture found. Replace tires on the same axle together so they share the load evenly. Make sure the new tires match the type your RV was built for, since trailer tires and light-truck tires are built differently and should not be mixed.
A blowout rarely damages only the tire. Flying tread tears out wheel wells, fender skirts, underbelly material, water lines, wiring, and brake lines, and the damage is often hidden behind a panel. If you have had a blowout, or you have bought a used RV and do not trust the tires, an inspection is the right first step. Horton RV Services in Calgary inspects blowout and road damage, repairs what the tire took out with it, sources the parts, and helps you document everything if you are going through insurance.
Tires are also part of any pre-trip check, so if you are heading into the mountains this season, have them looked at alongside the brakes, bearings, and hitch. It is a lot cheaper than a tow from the shoulder of the highway.
Common questions
How do I tell how old my RV tires are?
Look for the DOT code on the sidewall. The last four digits are the week and year the tire was made. If the code is on the inside sidewall you may need a mirror or a phone camera to read it. Age counts from that date, not from when you bought the RV.
Should I inflate my RV tires to the number on the sidewall?
Not automatically. That number is the tire's maximum cold pressure. The right pressure depends on how much weight the tire is actually carrying. Use the placard on your RV or the tire maker's load chart, and always check when the tires are cold.
What should I do after a blowout on the highway?
Get safely off the road, put the spare on if you can, and drive gently to the nearest safe stop. Then have the RV inspected before your next trip. Damage to wiring, plumbing, and brake lines from shredded tread is common and often hidden. Horton in Calgary can inspect it, repair it, and help with an insurance claim if one is needed.