Air or Nitrogen in Your Tires?

When I bought my new tires at Costco last fall, they filled them with nitrogen instead of air. When I asked the attendant what the difference between air and nitrogen was, he said, "not much." In addition, the main mechanic at my dealership said the same thing about nitrogen -- except that he said it was a "marketing gimmick."

Then I saw this piece from Bankrate on the difference between air and nitrogen in car tires. They list all the theoretical reasons nitrogen is a better option, but they then go on to debunk all those reasons. In the end, their conclusion is that there's not much difference between the two. Here's how they say it: 

When it comes down to a dollar decision, it's hard to argue that spending as much as $40 for nitrogen in a set of tires is a good fiscal move. Save your money and just keep an eye on your tire pressures.

My tires are rotated every 7,500 miles by Costco for free and they fill up the tires with nitrogen each time they rotate them. In the meantime, I fill them with air (I was told this was ok.) I don't think I'd buy nitrogen if I didn't already have it, but maybe others have some good reasons for doing so.

Anyone out there think nitrogen is the way to go?

Comments

[Compounding]

Oxygen is bad for most things... even humans (in excess). This is why we eat things with high anti-oxidants in them to avoid cancer. The article simply says it isn't important to switch to nitrogen because the atmosphere is mostly nitrogen anyways, and we are only eliminating a meager 21% that is oxygen... that isn't something to brush off... 21% is substantial... substantial enough for us to stay alive from breathing, and enough that we tend to actually have too much oxygen circulating in our bodies if we don't exercise regularly to burn it, or smoke to limit our intake. It makes a difference. It should dramatically slow dry-rot (although there is still the atmosphere on the outside that the tire is exposed to. I wouldn't outright pay for it... but if I could get a good deal on tires from Costco, and they offered nitrogen complementary, I would be all over it.

[fivecentnickel.com]

I think you should fill your tires with water. That way if you ever get stranded and are thirsty, you're all set. ;)

[Jonathan C]

Air is composed of >70% nitrogen already. I am not yet convinced that removing the ~20% oxygen is really going to help that much. And if it does slow dry-rot that much, why not try and figure out a way to remove the 20% oxygen from the air directly surrounding the tire exterior, and save even more?!

[El Indio]

Do you have to buy the tires at Costco to get that service?

[Eli]

If your tires were a closed system, you might make an argument (albeit a weak one). But they are not (hence your tires leak a little bit). At the same time, just as nature is trying to equalize the pressure inside the tires with the lower pressure outside, it is also trying to equalize the concentrations of elements both inside and out. So... buy the time your tires need air, they probably also have nearly the same chemical composition inside as they do out. And let's not forget that your tires are not going to get cancer. The outside of the tires will deteriorate much more quickly than will the inside, regardless of what they are filled with. Free nitrogen is probably fine, but I wouldn't pay a dime for pure nitrogen in my tires. Don't forget the rules that make the world go round...
INVENT something to fear. PROTECT people from what you just invented. ENTERTAIN them in the meantime, to keep them from asking questions.

[FMF]

El Indio --

I'm not sure. But if you didn't buy your tires at Costco, you'd certainly have to pay something for the service. For me, Costco had the best price on the tires I wanted and I got the nitrogen kicked in for free as part of their standard service.

[Carl Heldmann]

I never had a tire rot in 48 years of owning cars. I check tire pressure just by looking at them in a few seconds.Besides, my new Chrysler autos came with tire pressure sesors!

By the way, Earth's atmosphere contains 78.1% Nitrogen, not >70%.
If it's good enough for my lungs, it's good enough for my tires

[Compounding]

"And let's not forget that your tires are not going to get cancer."

Who said that they would get cancer? I was expressing how oxygen affects humans. I can give you something closer for automobiles, though... RUST. Oxygen corrodes things, and is really not that good for anything other than being a requirement for fire and metabolism.

It isn't going to make a whole lot of difference, and I even indicated this myself. But if it is free with tires that are already a good deal, I would definitely choose the nitrogen.

If you do not frequently drive your car, dry-rot can happen within a few months. There is a sizable population of people that do not drive that often. There are elderly people, there are people that travel for work. Heck, even look at trailers for hauling things like boats. In these situations, nitrogen would probably begin to have a case, even if you had to pay for it.

[Question]

- Compounding

I thought it was H20 that made cars rust faster.... Isn't that why cars say in Texas/AZ have less rust than cars in Chicago?

Just curious.....

[Terry]

I got new tires at costco not that log ago and while it may sound stupid - the first thing I noticed was some really ugly green caps on the tire stems. I told the guy I didnt need my car pimped out and to put the black ones back on. Apparently they use the different color cap with you use nitrogen.

[DAVID B]

I HAVE NITROGEN AND I GET MUCH BETTER GAS MILEAGE AND IT IS SUPPOSE
TO KEEP THE TIRES COOL WHEN DRIVING. I DO A LOT OF HIGH WAY MILES AND
I SEE A DIFFERENCE

[KC]

Question, the rust up north is due to the salt. Oxygen is what causes the rust, but the salt acts as a catalyst and speeds the process. Heat does the same thing, which is why exhaust systems rust much faster than the rest of the car. Heat + salt is just a deadly combination.

Nitrogen = scam. Placebo effects are very convincing.

[FMF]

Terry --

Ha! I didn't even notice that. But I looked last night and sure enough, I have green caps. ;-)

[Tommysno]

I've worked for an airline for nearly 20 years and always wondered why they fill aircraft tires exclusivley with nitrogen. I was told that pure nitrogen will expand and contract much less than atmospheric air. Very important when going from below zero temps inflight to 130+ degree runways. Not sure how much that would affect auto tires with much smaller temperature extremes.

[Builder]

Air is composed of >70% nitrogen already. I am not yet convinced that removing the ~20% oxygen is really going to help that much. And if it does slow dry-rot that much, why not try and figure out a way to remove the 20% oxygen from the air directly surrounding the tire exterior, and save even more?!

[Billy BoB Joe Bob]

The dumb dumb filled mine with nitrogen and didn't tell us and started mumbling a few days later on the phone and I found out they have to be topped off. Jipped....
Payed $220 for 2 tires and filled all four ( two replaced filled and two filled) I did not ask and I wish I never went if you want to see complaints go to google and type in costco tire hours I know I wasn't expecting complaints either!!!! I HOPE YOUR READING THIS COSTCO!!!

[Jim]

The only real reason I fill mine with Nitrogen is that when you use air, the moisture in the compressed air corrodes the edge of the aluminum/steel rim. When it starts to corrode, it either builds up on the rim or 'pits' it, causing the tire to slightly seperate from the rim causing a slow air leak. So on both of my vehicles (2009 Ford pick-up and 2005 Pontiac Grand Prix) I have used Nitrogen after the rims have been 'decorroded'. I think its just a preferance, but I believe the benefits outweight the cost.