Maintaining the Right Motorhome Tyre Pressure

Maintaining the Right Motorhome Tyre Pressure


A tyre behind a motorhome


The more you understand your motorhome tyres and how to maintain them, the safer your RV adventures will be — and the longer your tyres will last.


As a motorhome owner, it’s important to routinely check the air pressure in your vehicle’s tyres for safety, fuel efficiency and prolonging their lifespan.


In this blog, we discuss how motorhome tyres differ from car tyres, why having the correct tyre pressure is important and how to calculate the right tyre pressure. We also cover inflating your motorhome tyres and fitting a tyre pressure monitoring system.







Before taking a deep dive into how to care for your tyres, it’s important to check whether you actually have the correct type on your motorhome.


Most people naturally assume the tyres that come with their motorhome are the right ones — but factors like modifications, incorrect sizing and inadequate load ratings can make them unsuitable.


Find out how to choose the right tyres for your motorhome.




How do motorhome tyres differ from car tyres?


Mechanic showing the car wheel to a client in a garage


Most motorhomes are built on light truck platforms because they need to carry much heavier loads than cars. Beds, seating, cabinetry, appliances and water all add significant weight.


Certain tyres are designed and engineered for motorhomes. These tyres are more durable than car tyres — and they come with strong wheelsets designed to bear heavier loads.


Motorhome-specific tyres offer several advantages as they’re designed and built to:


  • Handle higher pressures and speeds safely
  • Have more rigid sidewalls to reduce vehicle sway — with a tougher tread compound.


To highlight this more resilient quality and ability to carry heavy loads, motorhome tyre sidewalls often come stamped with either:


  • RF — meaning reinforced, or
  • XL — which means extra load.

Light commercial vehicle tyres can also be used on motorhomes but are likely noisier with shorter lifespans.


Take a look at our buyers’ guide to motorhome chassis and construction.




Why the correct tyre pressure is important


Manufacturers of motorhomes and motorhome tyres spend considerable time and effort testing how each vehicle behaves with its tyres at different pressures. They can then recommend a maximum pressure setting. That way, you’ll know to keep your tyres inflated to that pressure — or a few pounds per square inch (psi) lower when driving in hot conditions.


The correct tyre pressure is critical to ensuring that your motorhome:


  • Tracks straight and true on the road
  • Maintains optimal braking and cornering performance
  • Maximises the lifespan of its tyres
  • Enhances your vehicle's overall efficiency — resulting in fuel and replacement tyre savings
  • Doesn’t suffer from a tyre blowout.


A set of tyres



How to prevent a tyre blowout


Preventing a tyre blowout is of absolute importance, and you can take several proactive steps to avert one. Monitor and rotate your tyres according to the manufacturer’s guidelines. Regularly check your tyre pressure and tread depth and look for any signs of damage — such as cuts and cracks.


Be aware of your load limits and avoid overloading your motorhome. Overloading can cause excessive heat build-up, leading to a tyre blowout.


Drive safely by keeping your speed under the limit and being cautious of road hazards, like potholes, debris and rough road surfaces.



Maintaining the correct tyre pressure


Check your motorhome tyre pressure before you travel. This is when your tyres are cold and the air inside them is at ambient temperature — which is the temperature of the air and surrounding environment where your motorhome is parked.


In warmer ambient temperatures, tyre pressure tends to increase due to the expansion of the air inside — leading to overinflation. The opposite happens in colder ambient temperatures as the tyre air contracts and underinflation is possible.


For more general maintenance tips, see our comprehensive guide on preparing your motorhome for winter road trips.



Motorhome tyres are designed to be inflated to higher pressures than car tyres, so restoring them to their recommended pressure using the local service station’s tyre inflator isn’t an option.


Most service station tyre inflators have a maximum pressure of 50 psi — though almost all light truck tyres have a recommended pressure between 50 and 90 psi.


Paul Owen — Award-winning motoring journalist




Calculating the right motorhome tyre pressure


Tyre pressure on a tyre pump machine


Check your motorhome owner’s manual to determine the recommended tyre pressure for each axle. It’s common to assume that every tyre on your motorhome needs the same pressure — but that’s not always the case.


Most digital and mechanical air pressure gauges can quickly display readings in:


  • Metric terms — kPa and bar
  • Imperial terms — psi.

However, if you need to convert one into the other, the formula is:


1 kPa = 0.145 psi


Using this formula, we can convert the maximum pressure of 44 psi for some car tyres into 303 kilopascals (kPa) or 3.03 bar.



Motorhome tyre pressure conversions





















Measuring air pressure


Most tyre inflators measure pressure in psi, while your owner manual probably lists the maximum recommended tyre pressure in metric terms — using either kPa or bar. To accurately determine the pressure in your motorhome tyres when psi is the only unit of measure available:


  • Download a digital pressure converter to your mobile device
  • Keep a physical conversion chart onboard
  • Invest in a tyre pressure gauge — that displays readings in psi and kPa (or bar).




How to inflate your motorhome tyres


It’s best to ensure your motorhome tyres have the recommended pressure before you hit the road — because finding a truck stop or tyre shop isn’t always easy.


Underinflated tyres can lead to excessive wear and increased fuel consumption while overinflated tyres are more prone to pothole damage and suffering uneven wear and tear.



Travelling with a portable air compressor


A fix and go kit


Consider purchasing a portable air compressor capable of pressurising your motorhome tyres to 120 psi or higher. A portable air compressor will give you:


  • The ability to check and inflate your motorhome tyres anywhere, anytime — ensuring optimal performance and less risk of experiencing a blowout
  • Peace of mind — and the confidence that you’ll be able to handle any tyre issues while travelling on the road.

You can buy a quality new air compressor like this ARB High Output Air Compressor (including the hose and accessories) for just a few hundred dollars.


If there’s room in your motorhome garage and the additional weight isn’t an issue, a portable air compressor could be your ideal tyre-inflating solution.



Touring without an air compressor


When on a road trip without a portable air compressor, and you need to check or inflate your tyres, plan to stop at a truck stop or tyre shop, such as:


Choosing to inflate your tyres at a truck stop or tyre shop is smart as these outlets have high-quality, reliable air compressors. You’ll also usually find they have knowledgeable staff who know about tyre maintenance.


Tyre pump machine at a service station


Do motorhome tyres leak air?


Motorhome tyres are similar to those fitted to other vehicles — they lose a couple of psi every month. This is the case even when the:


  • Valves and rubber are in good condition
  • Motorhome hasn’t been driven for a while.




Inflating your motorhome tyres with nitrogen


If your motorhome is parked or stored for several months, like over winter, it’s worth replacing the air inside your tyres with nitrogen gas. Nitrogen has molecules far larger than those of rubber, so it won’t leak through the molecular structure of the tyres over time.


Pure nitrogen is also less temperature-sensitive when you’re on the move. Any change in pressure due to ambient air temperature or rolling resistance will be relatively minor compared to the fluctuations of air-filled tyres.


American RV manufacturers often fill their vehicles’ brand new tyres with nitrogen gas at their factories due to the advantages over air, such as:


  • A longer life — nitrogen offers more consistent tyre pressure which reduces wear
  • Superior fuel economy — nitrogen inflation gives a more constant tyre pressure which has a positive effect on your motorhome’s fuel efficiency
  • Better road handling — a more stable tyre pressure improves traction and overall stability
  • Less corrosion — because nitrogen is a dry gas, you’ll enjoy reduced corrosion in your tyre rims compared to air.


A motorhome parked up beside a lake



When to use nitrogen


Should you always fill your motorhome tyres with nitrogen, never, or only before storing your RV for a few months? 


Filling your tyres with nitrogen has many benefits, such as enhanced safety through consistent pressure and reduced oxidation. But it also has a few drawbacks, like a higher general cost and the ongoing refilling expense. Nitrogen filling stations aren’t as widespread as those offering regular air — so availability can also be an issue.


Always use nitrogen if you travel often, prioritise tyre longevity and have easy access to nitrogen filling stations.


Never use nitrogen if you’re diligent about tyre maintenance and prefer convenience and cost savings.


Only use nitrogen before storing your motorhome if you wish to protect your tyres but don’t want the ongoing cost and effort of constantly using nitrogen.


Tyre shops with nitrogen

Tyre shops offering nitrogen inflation usually have their own nitrogen-producing system on site. They also have the hardware to purge your motorhome tyres of air before reinflating them with nitrogen.


When first exchanging air for nitrogen, your tyres must be purged and refilled several times to ensure they only contain nitrogen when the process is complete. This usually costs between $10 and $30 per tyre — while topping up a tyre that’s already inflated with nitrogen will cost you around $5 to $10.



Motorhome owners who’ve experienced nitrogen-filled tyres often boast that the only time their tyres lose pressure is when gauges are applied to the valves to check the pressure.


Paul Owen


Being safe around gas is important when motorhoming — both nitrogen gas in your tyres and LPG for running your motorhome appliances.




Understanding the effects of air temperature and rolling friction


Technician assembling a tyre


You may have already invested in a portable air compressor or decided that nitrogen is the best option for maintaining your tyres. Regardless, two crucial factors are still important to understand — air temperature and rolling friction.


Air temperature and rolling friction can affect tyre pressure, wear and longevity, as well as fuel efficiency and motorhome handling.



Air temperature


While touring around the country, your motorhome tyres will experience substantial temperature variations. The air temperature can change dramatically from day to night and from the sea to the mountains. Two scenarios are possible.


  1. As the air temperature increases, the air inside your motorhome tyres heats up — expanding and increasing tyre pressure.
  2. As the air temperature decreases, the air inside your motorhome tyres cools down — contracting and leading to a decrease in tyre pressure.



Rolling friction


Rolling friction, also known as rolling resistance, is the force that counters the motion of your motorhome tyres as they roll along a road surface. This resistance generates heat which causes the air inside your tyres to expand and increase in pressure.


Rolling friction is influenced by the:


  • Construction and tread design of your tyres
  • Motorhome’s weight, load and speed
  • Condition of the road surface.


Inflation pressure also plays a significant role. Overinflated tyres can result in a reduced contact area while underinflated tyres can have increased sidewall flexing — leading to higher rolling resistance.



Driving your motorhome on a relatively hot day, like 30 degrees Celsius, creates a dual issue where the pressure in your tyres naturally increases by around 20 percent.


Half of this pressure increase is due to higher ambient air temperature. The other half is the effect of tyre tread friction — transferring heat from a sun-baked road surface.


Paul Owen


Let’s assume your motorhome tyres have a maximum pressure of 80 psi and you set them at 70 before driving to your favourite campsite. During the hottest part of the afternoon, your tyres will gain pressure — bringing the psi measure closer to your tyres’ maximum.


On a cold day, the reverse can happen. Let’s assume you set your tyre pressure to their maximum of 80 psi at home in your garage. While driving, a loss of 0.19 psi can occur with every degree Celsius of ambient temperature drop.


If your tyres drop outside the optimal pressure range:


  • Braking and cornering performance will deteriorate
  • Rolling resistance and fuel consumption will increase.


Learn how to improve your recreational vehicle’s fuel efficiency.




Fitting a tyre pressure monitoring system


The best way to prevent a tyre blowout is to monitor your motorhome’s tyre pressure fluctuations. Fitting a tyre pressure monitoring system will alert you to any significant deviations from your tyres’ recommended pressure levels.


A tyre pressure monitoring system may come fitted in a new motorhome — or be available as an extra option. The touchscreen in the middle of your motorhome’s dashboard will display the pressure of your tyres, making them easy to monitor.


Technician checking a tyre pressure



Retrofitting a tyre pressure monitoring system


If your motorhome didn’t come with a tyre pressure monitoring system, retrofitting one is simple. However, it won’t be as well integrated into your dashboard because a separate screen must be installed.


Retrofitting a tyre pressure monitoring system is still worth considering as it will help prevent tyre issues with an advance warning when they’re reaching less-than-optimal pressure.



How a tyre pressure monitoring system works on a motorhome


Countless tyre pressure management systems are on the market. They all adhere to the same basic hardware format of four or six individual pressure-sensing valve caps.


Valve caps are small plastic or metal caps that screw onto the valve stems of your tyres. They send information via Bluetooth to a display screen on your dashboard.


Most tyre pressure monitoring system valve caps use thin-shaped batteries like this Maxlife Button Cell Battery for power. Keeping a packet of these batteries inside your motorhome is a wise move — so your tyre pressure monitoring system can remain in operation over a long multi-week tour.


Once the pressure-sensing valve caps are in place:


  1. The air pressure inside your tyres is continuously measured
  2. Pressure data is wirelessly transmitted to a central receiver inside your motorhome — either at regular intervals or when significant pressure changes are detected
  3. A warning light is triggered on your display — if a tyre’s pressure falls below or exceeds its recommended level
  4. You can correct the pressure issue by inflating or deflating your problem tyre
  5. The system will automatically reset or need to be manually recalibrated.


An advanced tyre pressure monitoring system may show you which specific tyre has the wrong pressure and its psi value.



Tyre pressure monitoring system prices can be under ten dollars for a four wheel car-oriented system ordered online from China. These cheaper systems usually have tiny LCD screens that are hard to read and will likely lose some bars of their numbers over time.


Prices can rise to around two hundred dollars for a six wheel motorhome-ready system with excellent weatherproofing, a display and an alarm for high or low tyre pressures.


Paul Owen


It’s clear how important it is to maintain the right pressure in your motorhome tyres. By knowing the basics of calculating tyre pressure and inflating your motorhome tyres, you’re taking positive steps towards safer journeys on the road.


A tyre wheel with a Fiat logo



Download our winter maintenance and safety checklist to look after your motorhome as a whole.



Technical Guides Maintaining Motorhomes