Got Nitrogen?

Not all car tires are filled with regular air, because some are filled with nitrogen!  If you ever walk by a vehicle and notice that the valve stems have green caps, you have probably seen a car with nitrogen in its tires. Nitrogen is frequently either used with cars that take trips around racetracks often, or vehicles that are not driven a whole lot.

However, if you are like us, you’re probably wondering why this is even beneficial for tires.

Well, we performed some research and here’s the story:

Scientists call nitrogen an “inert gas” because it doesn’t react much with other substances.  That’s the “inert” part. Contrast this with oxygen, a highly reactive gas that tends to react with just about every substance out there.  A great example: oxygen turns steel and iron into rust -a harmful chemical reaction involving cars if there ever was one.

Well, someone some time ago determined that by filling tires with a chemically-inert gas, like nitrogen, you would have a sealed environment where “aging” never happens. The tire’s inside would be permanently “new”.   Pretty cool idea, and it has other advantages as well, especially when the nitrogen you are using for your tires is at least 93% pure. Continue reading for more information!

Better Tire Pressure Retention

Over time, tires filled with air slowly lose pressure. Tires filled with nitrogen, on the other hand, maintain pressure for longer. explains that this is because nitrogen has larger molecules than oxygen and this makes them less likely to seep out through the permeable tire walls.

Moisture is Non – Existent

Air has moisture in it.  When you add compressed air to a tire, the water comes along for the ride. Tires have moisture in them and this may accelerate corrosion and rusting to age and rot the wheels. Because pure nitrogen makes it harder for moisture to run through it, the internal environment inside a nitrogen-filled tire is very dry.


Because of the moisture issue with air-inflated tires, nitrogen-filled tires could be to your advantage if you often drive in various extreme temperatures. Linking to the tire pressure issue above, temperatures greatly affect the level of pressure in tires. As nitrogen molecules are larger than air’s, nitrogen-filled tires do not make much room for moisture to build up because moisture’s growth is more predictable with nitrogen.

Better Fuel Economy

The EPA says that under-inflated tires may lower gas mileage by 0.3 percent for each 1 psi drop in pressure of all a vehicle’s tires. The theory is that since nitrogen loses pressure slower than air, you are more likely to be at the correct psi and therefore receive better fuel economy.

Where can you get it?

Many vehicle dealers are offering nitrogen as an “upgrade” on tire service.  Of course prices for this will vary, but recently we have seen this being around $8-10 per tire and about $80-90 each year per tire.  At the time this article was written, Costco was offering nitrogen fills as a no-cost feature with tire service.  For more information, contact your local vehicle dealer.

Article source: Hoffman General Motors

Leave a Reply

Your email address will not be published. Required fields are marked *