Filling your tires: nitrogen versus air

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Putting nitrogen in your tires can help reduce weight, but not by much. Image: Flickr / fsse-info / CC-BY-SA

Filling your tires with air now includes a multitude of decisions, including a decision about what type of air to use. Some enthusiasts say that filling tires with nitrogen will improve performance, but the cost may not be worth it.

History of nitrogen in tires

Originally, the idea of filling tires with nitrogen started in racing circles. Nitrogen won’t explode, so it started as a safety change; the tires would not blow up in the event of a fire. The nitrogen also helps cut a small amount of weight from the vehicles, which can help them run faster on a racing track. Nitrogen is a larger molecule, which means it seeps out of tires more slowly, which helps maintain a more consistent pressure.

The benefits of nitrogen

Reportedly, nitrogen can help everyday drivers in the same way race car drivers benefit. Nitrogen fill is a bit lighter than standard air fill and maintains pressure a bit better than air fill. The biggest difference is that compressed nitrogen is often much drier than air fill; compressed nitrogen will not contain moisture. Moisture in tires, over time, breaks down the rubber and can make the tire much weaker.

Breaking down the claims

Nitrogen filling can be a very expensive option, sometimes more than $40 per tire. Sometimes the cost is even more to bleed out the air and fill with nitrogen the first time around. The difference of weight between an air-filled tire and pure nitrogen-filled tire is a few ounces, a weight difference that will not do anything for the fuel efficiency of everyday drivers.

[Austin, TX Honda dealerships can walk you through the best options for your tires.]

The fact that nitrogen is much more dry than basic air fill is of benefit to most tires. Usually, condensation does build up in a compressed air line if it is not regularly cleared out. If you are filling your own tires with air, use a key or your finger to press down on the air nozzle to clear out any condensation.

Should you use nitrogen?

In the end, is it worth paying the premium to use nitrogen fill in your tires? Unless you are a race car driver or are an extreme hypermiler who counts every single ounce in the vehicle, nitrogen will likely not be worth the extra cost and effort. What you should do, however, is check your air pressure on a regular basis and ensure that your tires are wearing evenly.


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