Every RV owner should know the significance of tire pressure and how to monitor tire pressure in order to decrease the chances of tire blowouts and other problems that may arise. I was wondering what factors go into determining the tire pressure of an RV, so I decided to do some research on RV tire pressure.
The tire pressure on an average 16″ RV tire can be anything between 35-80 PSI or 280-550 kPa. That’s a wide range – and you need to find the right number for your specific weigh and number of wheels. Manufacturers provide data-plates in all RV’s that include the recommended maximum tire pressure, based on the maximum weight of the RV. Therefore, if you load your RV lightly, then your tires may be overinflated.
There are other factors that go into determining the correct tire pressure for the tires on your RV, but you should be alright if you base your decision on the manufacturer’s recommendation and make sure that your RV is not loaded too lightly. If it is loaded lightly, then make the needed adjustments so that you do not damage your tires.
In this article, I will go more in-depth on the topic of determining the tire pressure for the tires on your RV. I will also go over the basics of tire air pressure, the significance of tire pressure, what happens if your tires are under or over-inflated, where to find tire specifications, and how to monitor your tire pressure.
What is Tire Air Pressure (PSI) and Why It Matters
PSI, or pounds (of force) per square inch, is the unit of pressure chosen by most people in the US to represent tire air pressure. You may also see kPa mentioned here and there – that’s kilopascal, a unit which represents the same measurement but on a different scale.
Maintaining the proper tire air pressure is a matter of safety for you, the passengers you may have, and the vehicles that may be around you.
What Happens if Your RV Tire Pressure is Too High or Too Low?
Driving your motorhome or towing your travel trailer or 5th wheel with the wrong level of tire pressure can lead to all sorts of problems, affecting your stability, ease of ride and even gas mileage.
When RV Tire Pressure is Too High
The over-inflation of tires makes the sidewalls and tread of the tire harder than normal. This can limit the performance and traction of the tire. Also, it may cause uneven tire wear.
Also, tire pressure that is too high can cause a slight increase in gas mileage by reducing the rolling resistance of your tires.
Plus, overinflation will lead to a harsh ride, wobbly handling in the wind, and reduced braking effectiveness that is especially reduced on wet roads. If you’re towing a travel trailer, it could also lead to sway issues. Read more on how to prevent travel trailer sway in this post.
When RV Tire Pressure is Too Low
Most tire blowouts are caused by underinflation. Underinflation will force tires to come into contact with the ground more than properly inflated tires would.
To be more specific, the sides, or shoulders, of tires flex more when overinflated which produces an excessive amount of heat, and excessive amounts of heat lead to tire failure.
If your tires are under-inflated by just 10 or 15 psi, then the temperatures on the sides of the tires can reach 200 degrees Fahrenheit.
Is High or Low Tire Pressure More Dangerous?
There is a simple answer to this. Low tire pressure is more dangerous than high tire pressure.
Low tire pressure leads to dangerous blowouts while high tire pressure is generally less dangerous. This is true as long as your tires pressure is below the “maximum inflation pressure.” If you go over that, you could end up with a blowout as well. Of course, there are other safety issues associated with high tire pressure, such as increased sway when towing.
Overall – sticking to your right tire pressure recommendation is always best.
Where To Find Your RV’s Tire Pressure Specs
There is almost always more than one place to check your tire’s recommended specifications.
- On the Tire Itself (Sidewall)
- Owner’s Manual
- On the Sticker Inside the Vehicle
- Tire Placard on the Edge of a Vehicle’s Door
- Glove Box Door
- Fuel Door
How to Determine What the Correct Tire Pressure for Your RV
Setting the correct tire pressure on the tires on your RV is crucial to the tire performance, tire life, vehicle handling, and, most importantly, the safety of you and the people that are around you.
In order to get the best possible tire pressure, you should base your figures on the load being carried by the tires.
When you base the tire pressure on the load being carried by your tires, you ensure that the tires flex properly, are in the correct shape, will not produce an excessive heat build-up, and provide the strength to carry the total weight of your RV without losing tire patch (contact with the road).
Get Tire Load Information From Load/Inflation Tables
Tire manufacturer’s like Michelin here provide detailed tables for load & tire pressure.
The basic rule of manufacturers is to make sure that all tires on the same axle are set to the exact same pressure. This is based on the heaviest side.
Weighing an RV by axle positions and assuming that the load is equal on both sides of an RV is a bad idea. There is no way to calculate tire pressure without knowing the individual wheel weights. You could weigh the full axle, weigh one side, and then subtract from another side to get the weight of the other side.
Keep in mind that it is common for a difference of 1,000 pounds or more to be present between different sides on the exact same axle. Also, dual axles are close together, and they can be treated as a single unit (one wheel).
Get Tire Load Information From the RV Dataplate
The next best source of information is the RV dataplate. RV manufacturers are mandated by law to post a recommended tire pressure on the dataplate.
Manufacturers expect the owner to load the unit to its maximum weight. This is why they always post tire pressures based on the maximum weight of the RV.
You probably will load your RV lightly if you use the dataplate as a source. This will eventually lead to overinflated tires. Read the paragraph above to learn about the problems that can arise if you overinflate your tires.
On the flip side, you could load your RV beyond the axle rating (GAWR) or Gross Vehicle Weight Rating (GVWR). In that case, choosing to use the dataplate pressure will lead to under inflation.
Finally, using the dataplate as a source may not be a good idea because it does not take account the fact that an RV may be loaded in a remarkably unbalanced condition which is quite common.
It is important to understand that the pressure that is shown on the sidewall is not the maximum pressure for the tire. It is the minimum pressure needed to attain the maximum load rating of the tire.
Setting your tires can be set to the pressure indicated on the sidewall will lead to obtaining the design load rating of your tire. Keep in mind that the pressure indicated on the sidewall does not take into account all of the many factors that go into choosing the optimum tire pressure.