How Often Should You Replace Your Trailer Tyres?

Keeping your trailer tyres in good condition is one of the simplest ways to avoid breakdowns, improve safety, and stay compliant on the road. But unlike cars, trailer tyres often wear out from age and under-use rather than mileage – which makes knowing when to replace them less straightforward.

Here’s how to judge whether it’s time for a change and what to look out for.

The quick answer – it depends (but don’t wait for a blowout)

There’s no single mileage limit for trailer tyres because wear depends on usage, load, storage, and maintenance. A practical rule of thumb is to inspect tyres at every service and give them a thorough review every 8,000 miles or 12 months, whichever comes first.

You don’t need to replace tyres automatically at that point, but you should check for cracks, uneven wear, or any signs of hardening rubber. Frequent inspections help catch early issues before they turn into roadside failures – and can save both time and money.

Book a full inspection through our Servicing team.

Legal vs recommended – know the difference

For light trailers using car-type tyres, the legal minimum tread depth in the UK is 1.6mm across the central three-quarters of the tread. But relying on the legal minimum isn’t always safe.

Trailers often spend long periods parked, so the rubber can harden and crack even with plenty of tread left.

Age plays a big role. UV exposure, ozone, and temperature changes slowly degrade rubber.

Most tyre manufacturers recommend having tyres professionally inspected at around five years old and replaced by seven years, even if they look fine.

Stopping distances, wet-grip performance, and resistance to heat build-up all drop well before tyres reach the legal limit – so proactive replacement is always safer than waiting for failure.

What really wears trailer tyres out

Load and speed are the main wear accelerators. Running close to your trailer’s maximum payload or driving at sustained motorway speeds generates heat and increases wear.

Incorrect inflation and alignment also cause issues. Under-inflated tyres overheat and wear the edges, while over-inflated ones wear in the centre. On twin-axle trailers, misalignment or dragging axles can scrub tread away quickly.

Storage conditions matter too. Leaving a trailer parked for months can flatten the contact patch, creating flat spots. Exposure to sunlight, damp ground, or temperature extremes speeds up cracking and sidewall degradation.

Finally, driving environments – rough sites, kerbing, and frequent reversing on abrasive surfaces – all shorten tyre life.

Replace now if you see any of these

If any of the following signs appear, it’s time to replace the tyre – no matter the tread depth:

Tread below the legal limit
Uneven wear, cupping, or feathering
Persistent pressure loss or slow leaks
Cracks in the tread or sidewall
Bulges, exposed cords, or punctures in the sidewall
Noticeable vibration or heat build-up after short runs

These are clear warning flags that your tyres are no longer safe or roadworthy.

You can read more about tyre safety checks in our upcoming Trailer Safety Checks guide.

How to read tyre size, load index, and speed rating

A typical trailer tyre might be marked 185/70 R13C 96/94N. Here’s what that means:

185 – width in millimetres
70 – sidewall height as a percentage of width
R – radial construction
13 – rim diameter in inches
C – commercial construction (reinforced for load)
96/94 – dual load index (single/dual fitment)
N – speed rating

Always match the load index to your trailer’s maximum authorised mass (MAM) and expected payload. On twin-axle trailers, fit matched pairs on each axle for balanced handling.

If unsure, check your trailer’s handbook or identification plate, or speak to our Parts team for guidance.

Choosing replacements – like-for-like or an upgrade

Replacing tyres like-for-like is usually the simplest route – using the same size, load, and speed rating as the originals. Choose OE-equivalent quality or better, and always fit new valves.

For heavier or high-use trailers, upgrading to reinforced “C” (commercial) tyres can improve strength and lifespan. Look for tyres with strong wet-grip ratings and puncture-resistant designs.

When fitting new tyres, balancing and alignment checks are worthwhile – and it’s a good opportunity to inspect wheel bearings while the wheels are off.

Costs and budgeting

Tyre prices vary depending on size, construction, and brand. Commercial-rated tyres and premium brands cost more, but they tend to last longer and perform better under load.

Always get a fitted price rather than buying tyres alone – that should include valves, balancing (where needed), and disposal of old tyres. When you weigh up the cost, remember that a roadside failure can mean recovery charges, job delays, and potential damage – far more expensive than timely replacement.

Maintenance that extends life (and reduces costs)

Simple checks make a huge difference to tyre life and safety:

Check pressures before every tow, and adjust for load.
Torque wheel nuts after refitting and re-check after the first few miles.
Rotate tyres on twin-axle trailers if you notice uneven wear (follow manufacturer advice).
Store correctly – off bare ground, covered from sunlight, and ideally with tyre covers fitted.
Move the trailer occasionally to prevent flat-spotting.

Good maintenance keeps tyres in shape for longer and reduces unexpected costs. For a full guide, see our upcoming Pre-Tow Checklist.

FAQs

How many miles should trailer tyres last?
It varies widely. Usage, load, and storage have a bigger impact than mileage. Inspect tyres at every service and review condition around 8,000 miles or every 12 months for high-use trailers.

Do unused tyres ‘go off’?
Yes. Even if tread looks fine, rubber hardens with age and environmental exposure, reducing grip and increasing the risk of cracking.

Should I replace tyres in pairs?
Always replace tyres in pairs on the same axle to maintain even grip and handling.

Can I fit car tyres to my trailer?
Only if they meet the trailer’s load and speed rating, and construction requirements. Many trailers need commercial (“C”) tyres – check your plate or handbook first.

Ready to check your trailer tyres?

Don’t wait for a failure to find out your tyres are past their best. Book a Tyre Inspection with Three Shires Trailers – we’ll check tread, pressure, and age markings to keep you towing safely.

Contact our team today via our Contact page to book your tyre inspection or get a fitted price.

Takeaways

Replace tyres based on condition, age, and load, not just tread depth.
Inspect tyres at every service; review them at 8,000 miles or 12 months.
Maintain correct pressure, alignment, and storage to extend lifespan.
Don’t ignore cracks, bulges, or vibrations – replace immediately.