A complete motorhome tyre pressure guide, including advice on tyre and wheel safety
With the wheels keeping you moving and the rubber keeping you connected to the road, it helps to know how motorhome tyre pressures affect safety.
Motorhome tyres have a tough time: They support the vehicle’s weight, influence the ride quality, and impact the braking—whether it’s scorching summer, April showers, or icebound winter. Moreover, worn, incorrectly specified, or defective wheels and tyres can severely compromise your motorhome’s ride, cornering and breaking.
Motorhome tyres
Are they the same as van tyres?
Van tyres with the correct size, speed, and load rating are perfectly safe for motorhomes. You can also buy motorhome-specific tyres. Some manufacturers claim their motorhome tyres offer extra stability for rear-heavy vehicles.
Whether you pay a little more for motorhome tyres or stick to the tried-and-tested van tyres, we always advise buying premium tyres from brands such as Michelin, Continental, Pirelli, and Goodyear.
Budget tyres are tempting, but you won’t get the same ride quality or wet-weather handling and braking. Moreover, budget tyres tend to wear down faster than premium tyres, which may represent a false economy.
Tyre sizes and specifications
Your motorhome handbook contains the correct dimensions and specifications for your vehicle’s tyres. You’ll need the information to get a tyre price online or on the phone, and here’s what it means:
Your tyre size comprises imperial and metric measurements. Here’s an example based on a 225/75R16 tyre typically fitted to a Fiat Ducato motorhome:
- 225 means the tyre is 225mm wide
- 75 means the sidewall height is 75% of the tread width
- R indicates the tyre is a radial ply tyre, which means the inner chords that form part of the construction run at 90 degrees to the sidewall
- 16 means the tyre fits a 16″ diameter wheel rim
You’ll also notice a couple of other numbers next to the tyre size, like 116Q. In this case, 116 is the load rating, and Q is the speed rating.
Staying legal
The legal tread depth in the UK is 1.6mm across the central three-quarters of the tyre width. However, the handling and braking efficiency is reduced severely at this stage. The road noise may also be excessively high.
Most tyre and vehicle manufacturers recommend replacing tyres when the tread reaches 3mm. Some organisations recommend a change at 5mm tread depth, especially if you drive a lot in the winter.
Tyre pressures
Tyre pressure significantly impacts your tyres’ ride quality, safety and wear.
Overinflation creates an overly harsh, bouncy and unstable ride, while underinflation causes a motorhome to roll into corners. Overinflation and underinflation also cause uneven tyre wear and excessive fuel use.
The typical rear pressure for motorhome tyres is 80psi. However, the manufacturer’s recommendation will appear in the handbook, inside the fuel filler cap or in a doorwell.
Top Tip! TyreSafe provides a handy online tool for identifying the ideal motorhome tyre pressure based on single or twin rear axle, the plated maximum or fully laden axle load and the tyre size and load rating. Check out the FREE pressure check tool here.
We recommend checking your tyre pressures every two weeks. Mechanical pressure gauges display the results on an oversized dial, whereas digital gauges use numbers on an LED screen. The choice comes down to personal preference, but remember that digital gauges won’t work if the batteries run down.
Alternatively, you can use a battery-powered tyre inflation device with a gauge to check the pressure. Portable compressors like the Ring Automotive heavy-duty air compressor inflate fast, have a large gauge and are ideal to keep on board for emergencies.
Tyre pressure monitoring systems
Tyre pressure monitoring systems (TPMS) display motorhome tyre pressures on a digital screen in the cockpit or appear as a dashboard alert, depending on whether the unit is factory-fitted or an aftermarket device.
Factory-installed pressure monitoring systems work when a battery-driven sensor fitted inside the tyre sends a signal via a central control unit to the vehicle’s onboard computer. The alert system forms part of an MOT, and any defect in the system prevents a motorhome from passing the test.
Aftermarket systems like the TyrePal TPMS work by replacing standard dust caps with sensors that monitor tyre pressure. The system doesn’t operate via the motorhome’s onboard computer, and an error won’t affect your MOT.
Tyre maintenance
Motorhome tyres are subject to much more weight than car tyres, spend more time parked, and often in one spot. This creates conditions that need managing to keep your tyres in the best condition:
Keeping your tyres inflated correctly is vital. Check your tyre pressures every two to four weeks, even when parked up in the off-season. The correct pressures help prevent the side walls from cracking and flat spots developing.
Flat spots may also occur if your motorhome stays in the same place for a long time. Remember, you have approximately 3 tonnes weighing down on your tyres depending on your motorhome make and model. It’s a good idea to mark the tyre wall and the floor with chalk and drive your motorhome off the spot every three or four weeks. When you return, check the chalk marks so you know the contact point on the bottom of the tyres is different.
Another thing to be aware of is the impact of UV rays in sunlight. When one side of your motorhome is exposed to sunlight all day, UV rays can perish the rubber. Alternating nose-first and tail-first parking is an excellent way to switch the side facing the sun. Another trick is to cover the exposed wheels with purpose-made wheel covers. Also, tyre wall dressings like Autoglym High-Performance Tyre Gel contain chemicals that reduce the damage caused by UV rays.
Winter, summer and 4-season tyres
Winter tyres have chunkier treads with more gaps and little cuts in the blocks called snipes. They have a softer compound to work well in snow, sludge and low temperatures. Summer tyres have a tighter tread pattern, more rubber in contact with the road, and work better at high temperatures. However, winter tyres are noisier than summer tyres, wear down faster and are less fuel efficient.
Another option is a year-round tyre known as a 4-season tyre, which balances summer and winter characteristics.
4-season tyres suit motorhome owners who avoid extreme weather conditions. However, if you live in the Highlands and travel in the winter or plan to holiday in Spain during the summer, you may need a dedicated tyre. Fitting winter tyres on a spare set of steel rims is an option that means you only have to change the wheels, not the tyres.
Steel or alloy wheels?
There are no technical benefits to fitting alloy wheels to a motorhome. The choice comes down to personal taste. If your motorhome comes with alloys, then the choice is made. But if you are considering upgrading, there are a few things to consider:
First, choose a design that’s easy to clean. Spoked-style alloys may look sporty but are challenging to keep on top of.
Choosing wider wheels may affect the handling as wide tyres follow the camber, ruts and imperfections in the road. The experience is also known as tramlining.
Larger diameter wheels with a regular tyre profile may snag at the front on a full lock. Alternatively, larger wheels with low-profile tyres create a hard ride. Increasing your wheel diameter an inch or two from the stock size won’t cause a noticeable issue. But suppose you fit 20″ rims and ultra-low-profile tyres to a campervan. In that case, you’ll notice a significant difference in ride quality and handling.
Wheel and tyre maintenance
Check the tyres regularly for signs of cuts, nicks or foreign objects like screws or nails embedded in the tread.
Check the wheel rims periodically for signs of rust, cracks or distortions. Double-check bolt or stud holes for signs of elongation or deterioration. Alloys wheels don’t rust, but corrosion can weaken a wheel’s integrity, lead to slow air loss, or cause fractures when tightening wheel nuts or bolts.
Although you can repaint rusted steel wheels, this may affect the seal between the tyre and rim. You’ll also need to remove and refit or replace the tyres. Ultimately, if the wheels are in poor condition, then consider replacements. A professional can refurbish alloy wheels.
Plastic wheel covers on steel wheels tend to damage easily. Keep the rims secure with plastic cable tyres. But if the wheel covers crack, replace them straight away.
Tyre sealant pros and cons
If you get a puncture on a busy motorway or an awkward stretch of road, you’ll want to get underway again as quickly as possible.
Emergency puncture repair products such as Slime, Holts Tyreweld and Airman Tyre Repair Sealant are liquid chemicals you inject through the tyre valve. The treatments seal the puncture and reinflate the tyre. Although some products claim you can drive safely for up to 125 miles, these are temporary solutions and should only be used to get you safely to a tyre repair centre.
The benefit of using tyre sealant is time saved, but unfortunately, the tyre becomes irreparable, and you’ll generally need to purchase a new one.
Another system to consider is a pre-injected sealant like OKO Puncture Control. In this case, the chemical seals the puncture as soon as it happens. Once again, this is a temporary fix, and most garages won’t repair punctures contaminated with tyre sealant. The significant advantage, however, is your tyre won’t deflate when it punctures.
What Next?
Check out the other practical motorhome guides written by Caravan Information Services.