Have you ever noticed the shade of your RV’s tire valve caps? Ever noticed a green color in the valve caps. Well, if you did, the green doesn’t imply eco-friendly as you would normally think it would. It means that the tires of your RV are filled with nitrogen instead of air.
Nitrogen filled tires are something new out of the hat for general consumers, but they have been around for a long time. They have been used by highway equipment operators, the Federal Aviation Administration, and Military for various reasons in the past and still do today.
The cars used in NASCAR are filled with nitrogen to have consistent air pressure and to stay cooler. Quite recently, however, the practice of filling up tires with nitrogen has caught up with the mainstream market and we are witnessing more and more tire retailers and repair shops employing this.
So that begs the question, “Should you fill your RV or TT tires with nitrogen?”
If you have ever used an RV, you probably know what the two main expenses that occur while using your vehicle are – changing tires and filling up your gas tank. Any strategy that you can use to increase the life span of your tires or increase the mileage of your RV can be a godsend. Inconsistent tire pressure and under-inflation of tires lead to its premature wear.
Why is a Nitrogen Filled Tire a Good Idea?
Here is the thing – for every 10 degrees drop in weather, the life span of a tire can decrease by around 10%(source). Taking an example to explain what this can mean for your tire, let’s say you have something rated for 80,000mile and it requires 32psi of inflation. If you provide it with 29psi i.e you under inflate it, your tire loses about 8,000 miles. Now that’s a lot.
This is where nitrogen filled tires come into the picture. Advocates of nitrogen filled tires argue that nitrogen minimizes inconsistent and under-inflation of tires. It is also believed that nitrogen doesn’t leak as easily as air from tires, with the later leaking around three to four times faster.
Another theory which advocates of nitrogen filled tires say is that though air-filled tires do contain nitrogen (air contains 78% nitrogen), it is the oxygen in the air which leads to them performing worse. Oxygen corrodes the steel and aluminum wheels, which eventually leads to them under-inflating the tires. Tire pressure and its maintenance is crucial for safety and maintaining fuel economy.
When using air-filled tires, they contain moisture. Thus when we heat such fires, due to the moisture content, the pressure of the tires can waver. Nitrogen can be used to cool down the tires as it is inherently a dry gas. So there is no moisture present in the tires to heat up the tires and cause tire pressures to change.
How Much Does It Cost To Fill Your Tires With Nitrogen?
The best part about filling up your RV tires with nitrogen is that you do not have to purchase any new or special tires. Any RV tire or any tire for that matter can be filled up with nitrogen. A few tire companies our their sell nitrogen if you apply for their customer loyalty, using the hype for marketing. Some retailers might charge extra if the tires were not bought at their store.
Still, there are other retailers present who sell nitrogen filled tires at no extra cost. Depending on the size of the tire and the pressure, the cost of filling up your tire might vary. Still, the average costs stay between 3 dollars to 10 dollars, or sometimes even a bit more, depending on the tires you have.
First of all, filling up your tires with regular air costs you nothing at all, or at max a dollar maybe. So that is one thing to consider if you’re switching to nitrogen filled tires. You will have to shell out some money. If you have new tires, filling it up with nitrogen can cost around $70 to $150. On the other hand, just topping off your tire, which you usually do, can cost between $3-$10.
Normally, people top off their tires more than 4 or 5 times a year, so your yearly budget for tires in your RV is going to take a hit, no doubt about it. In the long run, the money you spend on these tires will be offset by the amount of savings you make by filling up less gas or changing tires less frequently.
Where can I fill my tires with nitrogen?
But one thing to note is that you cannot just expect to find nitrogen at any gas station. Right now, the only and best place to tip off your tires with nitrogen is with tire retailers or other big retailers. If you are located in the States or in Canada, there are several places where you can find this.
One of them is an online tool – GetNitrogen where you can find places to pump up your tires. There are a lot of other places you can find online, for example, Nitrofill, which allows you to do the same thing. It is always best to research a bit beforehand in your locality such that you can obtain the best deals.
Even if the pressure of the tires in your RV is low and you can’t find a place nearby to fill it up with nitrogen, just fill it up with air and get going. It would be perfectly safe; people have been doing the same for decades. You can refill it with nitrogen at the next available place after removing the air from the tires.
What Are The Advantages/Disadvantages Of Nitrogen?
Filling up RV and other tires with nitrogen have become a common practice. But like all things, nitrogen like the air has its share of advantages and disadvantages. Though nitrogen has been used for a long time in the military and car racing, commercial use has started to gain traction only recently. Let’s look at a few pros and cons of nitrogen –
- Nitrogen filled tires leak less than the ones filled with air. Tire pressure is crucial for safety and improving gas mileage and preventing wear and tear of tires. This leads to better fuel efficiency and less frequent tire changes. It is also something which needs to be checked frequently, as it is difficult to detect if a tire is under-inflated just by looking at it.
- It results in a longer life for your tires. As mentioned in the previous point, nitrogen filled tires maintain pressure better. Thus, you can expect your tires to last a lot longer.
- Lack of oxidation. Oxidation is one the main culprits which can corrode your steel and aluminum frames and can also make rubber brittle, thus resulting in it blowing out. Nitrogen filled tires have no oxygen in them. This oxidation does not occur as frequently.
- Better fuel efficiency. When the pressure of tires is not up to the mark, gradually the fuel efficiency of the vehicle will reduce. Nitrogen, as mentioned earlier releases pressure at a much slower pace than air, thus resulting in better fuel efficiency.
- Nitrogen filling of tires can lead to a more friendly and greener environment. It can be considered as a green alternative. Nitrogen filled tires result in better maintenance of pressure, which eventually leads to less fuel consumption and less frequent changing of tires. Thus, the demand for tires would decrease as more people shift to nitrogen tires and thus have to change them less. This would lead to less manufacturing of tires in the long run and eventually help the environment.
- A nitrogen filled tire requires a lot of maintenance. – Theoretically, if you have a nitrogen filled tire, it will result in better performance and more advantages if your routine maintenance is performed. But only if a tire is properly inflated will it give you the advantages that were promised, like less wear of the tires and better mileage. If a tire which is filled up with nitrogen is not inflated properly, it will result in the same amount of wear and gas mileage as you would see in an air-filled tire.
- So, the execution of the theory that a nitrogen filled tire will provide you with these advantages rests solely on the owner of the vehicle. This thorough and frequent maintenance is a mandate if you want to reap the rewards for the extra amount you put into nitrogen tires.
- Nitrogen filled tires are more expensive than air-filled ones. – Topping up your tires with air is usually free or costs a very small amount. The Federal Aviation Agency and the US military use nitrogen partly because of the weight, which benefits the vehicles. Topping up your tires with nitrogen can cost anywhere between $3 – $10 or even more. This can amount to around $100 per month for filling up your tires. This is definitely not a cheap proposition for most people and partly the reason why nitrogen hasn’t dominated the market yet despite more and more people moving towards it.
Is Tire Pressure The Same With Nitrogen?
Tires are used to carry the weight of your vehicle. Thus the pressure and consistency of the inflation of your tires are critical. Air consists of about 78% of nitrogen and 21% of oxygen, along with a few other gases like carbon dioxide, neon, argon, and others. How your tire behaves at different temperatures is affected by these gases inside air. As with the property of all gases, they will expand when hot and contract when cooled down. Thus with air-filled tires, the pressure rises and falls according to the temperature. Nitrogen gas does not expand or contract much with these changes in temperature. Thus the pressure in nitrogen filled tires remains more consistent.
Another thing to note is that molecules of nitrogen are much larger than that of air. Tires have really small holes in them which allow air to leak out in small amounts over time. As nitrogen molecules are larger in size, they leak less, and thus the pressure of the tires remain more constant.
In September 2006, Consumer Reports conducted research that lasted a year in which they evaluated tires filled with both air and nitrogen and put it outside for a year. The pressures of the tires were set to 30 psi. At the end of the testing period, it was found that nitrogen tires did indeed perform better at pressure loss and maintained the pressure of the tires better. The average pressure loss for nitrogen tires was 2.2 psi while their oxygen variants lost pressure at 3.5 psi on an average. Thus, nitrogen filled tires do in fact have a slight advantage over air-filled ones in terms of maintaining pressure.
So at this point if you are still on the fence, start asking your RV buddies what they do.
We fill all of our trailer tires with Nitrogen.