Motorhome tyres usually fail from age and standing, not from mileage. Like a caravan, a motorhome spends long periods parked under its own considerable weight, so the rubber perishes and flat-spots while the tread still looks deep. The two rules that keep you safe are: check the age and replace on time, and run the high pressures the weight demands.
Why motorhome tyres are different
A motorhome is heavy, often close to its axle limits, and stands idle for months between trips. That combination is hard on tyres: standing causes flat spots and lets the rubber perish, and the weight means any weakness is punished on a long, hot motorway run. A tyre with plenty of tread can still be unsafe, which is why age and condition matter more than wear.
The CP marking explained
Many motorhomes are designed for CP-marked tyres (the "CP" stands for camping/motorhome use). These are built with reinforced sidewalls and a higher load capacity to cope with sustained high loads and long periods parked. If your motorhome was specified with CP tyres, fit them again, and always match the load rating the vehicle requires. Your handbook or weight plate confirms what's needed. If CP tyres are not available in your size, a commercial (C-marked) tyre with at least the same load index is the usual alternative, but check with the motorhome manufacturer first.
Age and pressure checks
Read the four-digit DOT date on the sidewall (week and year) to find the age, see how to read a tyre's age, or type the four digits into our tyre date code checker. Continental advises that any tyre over ten years old should be taken out of service and replaced regardless of how it looks, because you cannot judge age-related deterioration by eye. For motorhomes the Caravan and Motorhome Club goes further: replace at five years and never use a tyre older than seven, whatever the tread. For tyres run at 50psi or more, it advises regular checks for deterioration from three years old and not using them once they reach five years. Pressures are usually much higher than a car's and depend on the actual axle weights, so set them to the figure on the plate, and check them cold before every trip, as under-inflation is a leading cause of failure.
Before every trip
A quick pre-trip routine catches the dangerous ones:
- Check the DOT date and replace if it's aged out.
- Inspect all the way round for cracking, bulges and flat spots, including the inner sidewall.
- Set the correct high pressures cold for the loaded weight.
- Don't forget the spare, which is often the oldest tyre of all.
Finding the right pressure for your motorhome
The correct pressure for a motorhome depends on the weight actually sitting on each axle, and the only reliable way to know that is a weighbridge. Two motorhomes on the same chassis can need different pressures because one carries a full water tank, a scooter rack and a bike, and the other does not.
- Load the motorhome as you travel: water, gas, passengers, food and everything in the garage.
- Visit a public weighbridge and ask for individual axle weights as well as the total. Many councils and some waste sites list them.
- Compare each axle weight with the plated maximum on the weight plate. If you are over on either axle you must remove weight; overloading is an offence, and DVSA and the police can stop and weigh a vehicle at the roadside.
- Look up the tyre manufacturer's load and pressure table for your exact tyre size and set each axle to the pressure for its measured weight.
CP tyres on the rear axle are often specified at a single high pressure by the tyre maker, far above anything a car runs, precisely because motorhomes sit near their limits and stand for long periods.
Follow the table rather than a car-based rule of thumb, and never set a motorhome tyre below the figure the manufacturer gives for the weight. Check pressures cold before setting off, because a long run on a hot day raises them, and let them settle rather than bleeding air from a warm tyre.
Protecting tyres during storage and lay-up
Most of the ageing on a motorhome tyre happens while it is parked, so how you leave it over winter matters more than how you drive it in summer. A few simple habits slow perishing and prevent the flat spots that make the first spring trip feel like driving on square wheels.
- Inflate to the top of the recommended range before storage. A tyre that sits soft under a heavy vehicle flat-spots and cracks at the sidewall far faster.
- Move the vehicle a short distance every few weeks so the same section of tread is not carrying the load all winter. Even a metre forward or back helps.
- Keep the tyres out of direct sunlight with tyre covers or by choosing the shaded side of the storage site. UV is the main driver of sidewall cracking.
- Park on a firm, clean surface. Gravel, wet grass and oily concrete all attack rubber. Boards under the wheels are a cheap fix.
- Do not park with a wheel on a levelling ramp edge for months. The concentrated load creates a permanent deformation.
- Consider taking weight off the tyres on a long lay-up by using axle stands or purpose-made tyre saver cradles, following the chassis handbook.
Check pressures again before the first trip, because they will have dropped.
Motorhome tyre law and the MOT
The same tyre law applies to a motorhome as to a car: 1.6mm of tread across the central three-quarters of the width and around the full circumference, no cuts reaching the cord, no bulges, and tyres that are suitable for the weight.
Each illegal tyre can attract a fine of up to £2,500 and three penalty points, and the rules are set out on GOV.UK.
The MOT checks tread depth, sidewall condition, and that the tyre's load and speed ratings are appropriate for the vehicle. A perished sidewall with visible cracking can be an advisory or a failure depending on how deep it goes, and a tyre whose load rating is below what the axle needs is unsafe whatever its condition.
Tyres of different size or structure across the same axle are a failure too.
The tester is not measuring age, so an old tyre that looks sound will pass. Do not read a pass as a clean bill of health on age. TyreSafe recommends regular checks of pressure, tread and condition, and for a vehicle that stands idle, we add the date code to that list.
If a motorhome tyre fails on the road
A blowout on a heavy motorhome pulls hard, so the priority is to keep it straight and slow down gradually rather than braking hard. Hold the wheel firmly, ease off the accelerator, let the speed bleed away, and only then brake gently and steer to the safest place off the carriageway.
Read what to do in a tyre blowout before you ever need it.
On a motorway, the Highway Code breakdown rules (rule 275 onwards) apply: get everyone out through the doors away from traffic, stand behind the barrier well away from the vehicle, and call National Highways on 0300 123 5000 from an emergency phone or your mobile.
If you cannot get off a live lane, stay belted in with hazards on and dial 999. Do not attempt to change a motorhome wheel on a hard shoulder or in a refuge area; it is heavy, the jack is marginal on soft ground, and the traffic is passing at speed. Wait for recovery to a safe place.
Away from the motorway, at a campsite, storage yard or on a quiet road, a mobile fitter can bring and fit the correct CP or commercial tyre to the vehicle. Our burst tyre and emergency tyre replacement pages explain what a mobile fitter can do; tell us the vehicle and tyre size when you call and we will confirm whether we can fit it.
We come to the motorhome
There's no need to drive a heavy motorhome on doubtful tyres to a garage. Tell us the motorhome, its tyre size and where it is kept, and we will confirm on the call whether we can fit it at your home or storage site within reach of our Brent Cross base, checking age, pressures and condition while we're there.
