Nitrogen vs. Air in Tires: Which Is Better?

Whether you're installing new tires or maintaining existing ones, air isn't your only option when it comes to inflation. You can also use nitrogen, and it's the preferred choice for some drivers. Is nitrogen the ideal choice for your needs? Let's take a closer look.

Why Put Nitrogen in Tires?

Nitrogen is used in some situations for reasons that involve safety and/or performance.

Let's start with safety. Nitrogen is an inert gas. It's non-flammable, and it consists of little more than air with the oxygen removed. It doesn't support moisture, and it doesn't support combustion. Because of these qualities, nitrogen can be safely used in applications that are unusually demanding.

You'll find nitrogen tires on airplanes. They are also found on vehicles used in the mining industry. And nitrogen tires are used in a wide variety of commercial applications that involve heavy usage and heavy loads.

Now let's look at nitrogen's effect on performance. According to Chemical & Engineering News, nitrogen produces less tire pressure variation than air. Why is this the case? Well, nitrogen molecules are larger than compressed air molecules, and they move more slowly. Because of these qualities, nitrogen won't escape from a car's tires as quickly as air will. This can help nitrogen tires maintain a pressure that's more consistently stable than the pressure they'd have if inflated with air. This can optimize a car's handling. It can also help a car achieve optimal fuel economy.

Within the automotive world, nitrogen tires are often used in professional auto racing. Even the smallest differences in tire pressure can impact a racecar's performance. Given its advantages when it comes to maintaining steady tire pressure, it's easy to see why nitrogen is a better choice than air for inflating tires in vehicles that are built to go fast and compete to win.

Nitrogen vs. Air in Tires: Which Is Better?

So, which is better: nitrogen or air? Each has advantages and drawbacks.

In everyday use, nitrogen offers one key advantage over air: With nitrogen, tire pressure fluctuation is reduced. This stable air pressure can help ensure that your car handles at its very best. It may also help you maximize your car's fuel economy, and it could ultimately help to optimize the life of your tires.

The key drawback to using nitrogen is that it's less widely accessible than air. If you want to use this gas, you'll need to figure out where to fill nitrogen tires. Also, nitrogen may cost more than compressed air when getting your tires inflated.

Air doesn't have the same tire pressure advantages as nitrogen. But it's a more convenient option; it's more widely available and it's typically cheaper to purchase.

Tips for Nitrogen Tires

Want to learn more about nitrogen tires? Inflating with nitrogen has its own unique quirks and idiosyncrasies.

Here are some tips to keep in mind:

Adding Air to Nitrogen Tires

If your car has always had nitrogen tires, there may come a time when you need to make the switch to air for one reason or another. So, can you put air in nitrogen tires?

If your nitrogen tires need inflation and nitrogen isn't available -- or if you'd simply rather use air -- you can inflate the tires with air. This is perfectly safe and won't trigger any kind of harmful chemical reaction.

Mixing Air and Nitrogen

Here's a common question people have: Can you mix air and nitrogen in tires?

If your tires contain some nitrogen, you can safely add air; mixing air and nitrogen in tires is safe. However, if you add air, it will compromise the purity of the nitrogen. This means that nitrogen's advantages when it comes to helping your tires maintain stable pressure will be minimized.

How to Put Nitrogen in Car Tires

If your tires are running low on nitrogen and you need a refill, you'll need to find a local nitrogen dealer. The dealer will be able to handle the task of inflating your tires. Unfortunately, finding a source for nitrogen can be harder than finding a source for compressed air.

How to Check Nitrogen Tire Pressure

We've mentioned that nitrogen is superior to air when it comes to helping your tires maintain stable pressure. Keep in mind that it's still necessary to regularly check tire pressure, even if your tires are filled with nitrogen. Tires filled with nitrogen lose pressure more slowly than tires filled with air, but nitrogen tires still experience pressure loss over the long term. This can ultimately cause problems with underinflation if the tires aren't properly maintained.

You can use a standard tire pressure gauge to check the pressure of nitrogen tires.

Final Thought

Underinflated tires are a huge safety hazard. Even though nitrogen tires maintain more consistent pressure than those inflated with air, they can become underinflated with the passage of time. Whether you have air or nitrogen tires, it's important to check the pressure regularly and keep them properly inflated.