Does filling your tires with nitrogen save you gas?  There is a large group of advocates who say yes.  Here is why they say that.          

One of the biggest drains on fuel economy is under inflated tires.  The National Highway Traffic Safety Administration says that properly inflated tires  can improve gas mileage by nearly 3 percent. The EPA estimates that at least 30% of the cars on the road have at least one under inflated tire.

It is estimated that drivers in the US aggregately loose more than 2 million gallons of gas every day due to under inflated tires. Decreased air pressure causes the tire to flatten which creates more surface area between the tire and the road. The greater surface area increases friction which causes the engine work harder.

When an engine has to work harder it burns more gas. More tire surface due to under inflation means it takes more power to roll that tire. More power needed means less fuel economy. A tire that is correctly inflated is going to roll more easily using less power from the engine and less gas.

What does this all have to do with nitrogen?  I’m getting to that.  So we have established that under inflated tires use more gas.  Why do tires become under inflated?  The simple answer, it looses air. That doesn’t mean you have a leak.

Tires are made with permeable materials.  That means that the small air  molecules can escape from the tires over time.  As the molecules of air escape the tire looses pressure.  It is a natural occurrence for all tires.  That is why it is suggested that you should check your tires once a month.

A tire that is inflated with Nitrogen looses its pressure 3 times slower than if it were inflated with air.  This is because Nitrogen is denser than Oxygen which means it has larger molecules and will seep out of the tire less easily than air. That will result in a significantly slower loss of tire pressure over time.

Since your tires will loose pressure more slowly they will maintain themselves at close to the optimum pressure longer then they would with air. That means less under inflated tires, less friction, and less gas needed to move your car forward.

That is how nitrogen helps you get better fuel economy.  The cost of filling your tires with nitrogen is around $10.00 per tire.  Is it worth it?  Those who advocate nitrogen say absolutely it is.  However there are those that don’t agree. Before you run off and spend $40.00 getting your tires filled with nitrogen it might make sense to hear from the other camp.