WHY CAR TIRES CAN BE FILLED WITH NITROGEN? (7 BENEFITS EXPLAINED, FAQ)

Your tire dealer or garage may offer the possibility of inflating car tires with nitrogen instead of air. What are the benefits, and when should you opt for this solution?

Filling a car tire with air or with nitrogen – which one is better? Image credit: Alius Noreika / Copilot Designer

Can you fill car tires with nitrogen gas instead of regular air?

If you’re wondering if you can do this trick with your own vehicle, then the answer is yes: it’s possible to fill car tires with nitrogen gas instead of regular air.

Some people opt for nitrogen because it has certain benefits over regular air, such as maintaining tire pressure more consistently over time, reducing oxidation and corrosion inside the tire, and potentially offering better fuel efficiency.

However, it’s important to note that the differences between nitrogen and regular air are relatively minor for everyday driving, and many vehicles operate perfectly fine with regular air in their tires. Additionally, nitrogen filling usually comes at an extra cost, so it’s essential to weigh the potential benefits against the added expense.

Nitrogen in car tires: What are the benefits?

Nitrogen constitutes a significant portion of the air we breathe, comprising 78%. Considering that tires filled with nitrogen contain approximately 93 to 95% nitrogen, the disparities between nitrogen-filled and air-filled car tires are present but not substantial. Here we will discuss these benefits in detail.

Inflation pressure stability

One of the most important factors when discussing car tires is the optimal tire inflation pressure. It affects the safety, fuel consumption, and tire lifetime. However, the inflation pressure rises and falls when temperature changes. It’s due to a well-known fact that gas expands when heated and contracts when cooled. This fact is also valid for tires: every 6 degrees Celsius results in a shift of almost 1 PSI (pound per square inch).

That’s where nitrogen gas shows its benefits: it is less sensitive to temperature changes when compared to regular air. That means the tire pressure varies less when they are inflated with nitrogen.

Nitrogen doesn’t support moisture or combustion

Air contains roughly 78 percent nitrogen, 21 percent oxygen, plus miscellaneous gases, including water vapor and carbon dioxide. In contrast, nitrogen is an inert, non-flammable gas. The absence of oxygen and water diminishes the risk of corrosion.

Less gas bleeding from tires

Nitrogen molecules are larger than oxygen molecules. That makes it harder for them to leak out, and PSI stays steady in the long term.

Being slightly larger nitrogen molecules escape from tires at a slower rate. The difference in the rate of air and nitrogen loss is approximately 1.6 times. However, it’s essential to note that even nitrogen-filled car tires are exposed to external oxygen, which can influence tire performance.