What Trailer Owners Should Know About Tyre Care and Maintenance

Most trailer and caravan tyres don’t wear out. They age out. Sun, long idle spells and the wrong tyre pressure ruin the rubber well before the tread runs low.

This guide covers how age shows up, which pressure and storage habits cause damage, and what to check before each trip.

Why do these tires age out before they wear out?

Trailer tyres often fail from age before they wear out because they sit parked in the sun for months between trips. Tread depth tells only half the story.

Every tyre carries a DOT code. The four digits after “DOT” give the week and year of manufacture, and age counts from manufacture, not from the day the tyre was fitted. Common guidance says to replace them at around 5 to 7 years, even when the tread looks fine.

NZTA’s inspection manual for trailers lists significant perishing from age, moisture or exposure as a rejection reason. It also lists bulges and cracks over 25 mm long that reach the cords. The manual sets conditions, not an age limit, so a pass doesn’t prove a tyre is sound.

Age is one hidden problem. Pressure is the other.

Which pressure mistakes do owners make most?

Guessing pressure from tyre size is the most common mistake. Pressure depends on the actual load on the axle, and caravan tyre pressures usually run higher than a car’s.

Leisure tyres on caravans and campers carry heavy loads close to their limits. The right pressure stops the tyre flexing and overheating, so check it with a tyre pressure gauge before every trip, with the tyres cold.

Load rating matters too. Match the tyre’s load rating to the trailer’s weight, and fit matching tyres on each axle. NZTA lists mismatched ply ratings, or load indices more than 2 apart, on a light trailer axle as a rejection reason.

Even the correct pressure can’t fix a tyre that spends months baking.

How should you store them between trips?

Keep them out of direct sun, and don’t leave them sitting on one patch of ground for months. UV and ozone crack the rubber, and a standing tyre loses pressure.

• Cover the tyres or park in shade, since UV drives most of the aging.

• Check pressure regularly, because a parked tyre still leaks air slowly.

• Look over the sidewalls for fine cracks, and book an inspection if you find any.

• Clean off oil, fuel and paint, and pick stones out of the tread.

Good outdoor tyre care means skipping one common shortcut. Tire shine isn’t UV protection, so don’t rely on it. A cover does that job.

Storage keeps the rubber healthy. A short routine before each trip catches what storage misses.

What should you check before every trip?

Run through four checks before you hitch up. They take a few minutes, and they catch most of the problems above.

• Read the DOT code, and note how old each tyre is.

• Set cold pressure for the load you’re carrying.

• Look for bulges cuts and sidewall cracks, including on the spare.

• Check for a string repair that shows from outside, since NZTA lists it as a rejection reason.

A string plug is a roadside fix. A proper repair from the inside is the safer follow up.

Keeping the right kit on hand makes all of this easier.

Where can you buy repair kits and gauges in New Zealand?

Pair these tyre maintenance tips with a tyre pressure gauge, a tyre repair kit and spare valve caps kept with the trailer. Match the kit to the tyre type.

Rema Tip Top NZ is one supplier. Its web shop lists repair kits under Outdoor & Leisure, alongside inflation gauges and valve caps elsewhere in its range.