Caravan and trailer tyres: why age matters more than tread

The short answer Caravan and trailer tyres almost never wear out — they age out. A tyre with 7mm of tread that has spent six years standing in one spot can be structurally finished. Check the date code, not just the tread, and replace on age regardless of how new the tread looks.

The failure that ruins a holiday is a blowout at motorway speed on a caravan tyre that looked perfect. It looked perfect because tread depth was never the problem.

Why standing still is hard on tyres

• UV and ozone degrade the rubber whether or not the wheel turns. A caravan parked outside is exposed all year.
• Flat-spotting. A tyre carrying load in one position for months takes a set, and the carcass is stressed in that spot.
• No flexing. Tyres in use distribute protective waxes through the rubber as they flex. A static tyre does not, so it dries and cracks sooner.
• High load, small tyre. Caravan tyres often run close to their load limit, which leaves little margin for age-related weakening.
• Sustained motorway speed on the few days they are used — heat with no gentle warm-up.

Read the date code

Every tyre carries a DOT code ending in four digits: the week and year of manufacture. 3219 means week 32 of 2019. It is on the sidewall, sometimes only on the inner face, so you may need to look at the back of the wheel.

Age guidance for caravans and trailers Industry and caravan-club guidance commonly recommends replacing caravan tyres at around five years from manufacture, and treats seven years as the outside limit regardless of appearance. This is a recommendation rather than a legal limit for ordinary trailers, but it reflects how these tyres actually fail. How long tyres last explains the date code in more detail.

Pressures are higher than you expect

Caravan and trailer tyre pressures are set by the caravan or trailer manufacturer based on its loaded weight — not by your car's placard and not by the maximum figure on the tyre sidewall. They are frequently much higher than car pressures.

Under-inflation is the classic cause of caravan tyre failure: the tyre flexes, builds heat over a long motorway run on a warm day, and lets go. Check them cold, before setting off, every trip.

The towing vehicle needs attention too — nose weight loads its rear axle, so its laden pressures apply. See tyre pressures for loads and towing.

What to inspect before a trip

1. Date code on every tyre including the spare.
2. Pressures cold, to the caravan manufacturer's figures.
3. Sidewall cracking — fine crazing is age; deep cracks mean replace. Check the inner faces too.
4. Bulges or flat spots. Any bulge means replace, no exceptions — sidewall damage and bulges.
5. Tread depth — the legal minimum for most trailers matches cars at 1.6mm, but tread is rarely the limiting factor here.
6. The spare, which is usually the oldest and least checked tyre on the outfit.

Storage: the cheapest thing you can do

• Keep them out of direct sunlight — covers help, as does parking under shelter.
• Move the caravan periodically so the tyres do not stand on the same spot all winter.
• Keep them inflated while stored; a soft tyre deforms under load.
• Consider winter wheel removal and storing the wheels indoors — storing tyres properly.
• Keep them away from electric motors, which generate ozone.

Fit the right type

Many caravans and trailers require tyres with a C marking (commercial) or a specific reinforced construction and load index. Car tyres in the same nominal size are usually not an acceptable substitute, because the load rating is what matters — van tyres vs car tyres covers the same principle.

Some trailer tyres also carry a speed limitation that is lower than a car tyre's. Check what is specified rather than what fits.

Common questions

My caravan tyres have loads of tread. Do I really need new ones?

If they are past about five years, very probably. Tread depth tells you about wear; it tells you nothing about whether the rubber and carcass have degraded.

Is there a legal age limit?

For ordinary caravans and light trailers there is no general age limit in law — the requirement is that the tyre is in a fit condition. Age limits do apply to some heavier commercial vehicles and buses. The five-year guidance is best practice, and we would follow it.

Can a caravan tyre be repaired?

Sometimes, under the same rules as any tyre — but given how these fail, replacement is often the better call on an older one. See can a puncture be repaired?

Can you come to a storage site?

Usually yes, provided there is space to work and access. It is often easier than towing an outfit on tyres you do not trust — call and describe the site.

Before the season starts

The sensible time to sort caravan tyres is before the first trip, at the storage site or at home, rather than on a hard shoulder in August. Call 07989 606060 or see mobile tyre fitting.