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Monday, October 6, 2008

Nitrogen in Tires

The big buzz in the automotive world today is whether filling your tires with nitrogen instead of air is beneficial. NASCAR has been using nitrogen in tires for years, so what do they know about nitrogen in car tires that you don’t?

Well for starters, what NASCAR knows and what you may not know is that you are already inflating your tires with nitrogen, true story. But then again, you are also filling your lungs with nitrogen when you breathe. You see the air that you breathe and the air in your tires is the same and is made up of 78% nitrogen and 21% oxygen and 1% of other gases.

Next lets look at the pros and cons, one pro is that nitrogen is said to improve gas mileage because nitrogen is not vulnerable to pressure changes since it doesn’t contain any moisture. Regular air can hang on to moisture that leads to the air constricting and intensifying considerably more under temperature changes. When it gets cold outside, the moist oxygen decreases, giving way to a decrease in tire pressure. This decrease in pressure facilitates a reduction in gas mileage since there's more tire on the road to generate friction. Increased friction forces the engine to work harder just to move the vehicle forward. On the other hand, in exceptionally hot temperatures, normal air in tires can expand to a potentially unsafe pressure level.

Nitrogen molecules also have a minimal chance of trickling through the tire's rubber walls assisting the tires in preserving their best possible pressure for a greater period of time. Regardless of nitrogen or air, a properly inflated tire should provide you with better gas mileage compared to an under-inflated tire. NASCAR fills their tires with nitrogen because they are looking to squeeze every extra drop of performance out of the car that they can.

The next pro for nitrogen in tires is that it can improve driving safety. 660 highway fatalities and 33,000 injuries happen each because of accidents that are connected to low tire pressure, according to the National Highway Traffic Safety Administration. AAA reports that nearly 4 million of its service calls are because of tire issues. Regardless of whether you use nitrogen or air, driving on properly inflated tires can increase handling and control by maximizing the contact area between the tire tread and road surface.

The most important con here is how much that it costs to fill your tires with nitrogen. The average cost for filling your tires with nitrogen is $10 per tire and when using nitrogen valve stem caps need to be replaced more frequently, plus you will need to locate a manufacturer or supplier of nitrogen in your area.

There haven’t been any studies or documentation that proves beyond a doubt that nitrogen does indeed improve fuel efficiency. It all sounds good, but there just has been enough research to support the theory that nitrogen is better for your tires.

Unless your drive in NASCAR, you don’t really need nitrogen in your tires. It’s okay if you’d like to spend a little more to fill your tires with nitrogen to gain the perception of increased gas mileage and less frequent tire refilling. But the truth of the matter is, it's only a perception. The best thing that you can do for yourself and your car is to make sure that your tires maintain their optimal pressure year-round and save the extra money and hassle.