It is widely known that most Costco locations provide nitrogen tire inflation with the purchase of a new set of tires. However, Costco will not provide nitrogen for tires already purchased and filled with air. It is only available on a new set of tires. So where do you go if you want nitrogen filled tires but are not in the market for new tires? Get Nitrogen, a consumer group that espouses the benefits of nitrogen tire inflation, provides a free nitrogen tire inflation dealer locator that lists local stations that offer a nitrogen inflation service. Check it out and go green with nitrogen tires.