Nitrogen in your car tires can marginally reduce air-loss, just don’t use it to replace regularly checking tire pressure. [ConsumerReports]


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  1. blue_duck says:

    Well, whaddya know..

  2. DarthSensei says:

    Nitrogen makes up almost 80% of air anyway. This is primarily a marketing scam.

  3. topgun says:

    Oh, there are plenty of benefits: (1) Cool fluorescent green valve stem caps (assuming your nitrogen vendor has any marketing savvy), which will look sharp with your spinning wheel covers. (2) Bragging rights. OK, you were behind the curve with cell phones, iPods, thong underwear, etc. Nitrogen in tires is relatively new to the mass market. Now’s your chance. (3) Reduced fire danger next time you land your space shuttle or commercial aircraft, and tell me you won’t sleep better knowing that.

    Most tires are filled with compressed air, which when dry consists of about 78 percent nitrogen, 21 percent oxygen, and 1 percent other gases by volume. Water vapor (humidity) can make up as much as 5 percent of the volume of air under worst-case conditions. Filling your tires with nitrogen mainly does two things: it eliminates moisture, and it replaces skinny oxygen molecules with fat nitrogen molecules, reducing the rate at which compressed gas diffuses through porous tire walls. That means, theoretically at least, that a tire filled with nitrogen retains optimal pressure longer, leading to more uniform tire wear and better gas mileage. The commonly quoted figure is that tires inflated to 32 psi get 3 percent better mileage than at 24 psi

  4. UnStatusTheQuo says:

    I did this a year and a half ago both in my wife’s Honda and my Trailblazer. I did notice an improvement, especially in Chicago winter. Since my repair shop usually gives it free with an oil change, it’s a no-brainer.