Dumb question....

[Old Guy]

What's the purpose of filling up tires with Nitrogen? I noticed that on the window sticker of a vert I looked at the other day that the tires were filled with nitrogen. Does anybody besides dealers fill tires with nitrogen? What type of costs are associated with this? Thanks in advance...

[outlaw2]

Navy/USMC aircraft tires use nitrogen, The atmosphere is 78% nitrogen 21% oxygen and 1% argon and other gases but for use in a daily street machine I think is a bunch of hot air that costs $$$ not like your coming in for a landing at 100+ mph. Question? Do the dealers really have a nitrogen cart in the bay just for tires or are they using an air compressor and charging nitrogen prices?

[fielderLS3]

In theory, the variation in pressure caused by changes in temperature is slightly more predictable with pure gas than a mix of 78%N, 21%O, and .93%Ar.

The real reason is that depending on all kinds of meteorological factors, water vapor can make up anywhere from 0 to 4% of the atmosphere. (The above percentages are for "dry" air). If you just use compressed air, water vapor in the air will cause condensation inside your tires anytime the temperature inside your tires falls below what the dew point temperature was when they were filled.

It's really just a minor issue with street cars, but something small like that can have an effect where more precision is needed, like on race cars, or aircraft, etc....I just use an air compressor, but try to only add air on days with lower relative humidity.

[OrangeVert]

Nitrogen fill was free with my new tires at Costco on my Toyota pickup a few years back. They used green valve stem covers to indicate they were filled with nitrogen instead of air.

[FirstandFifthGen]

Nitrogen pressures won't vary as much with temperature changes as air, and it's molecules are larger and thus will not tend to leak as easily over time.

[Sttt5126]

I have nitrogen in all of my vehicles tires...cadillac srx and gmc sierra.

[wilmaya]

Originally Posted by FirstandFifthGen

Nitrogen pressures won't vary as much with temperature changes as air, and it's molecules are larger and thus will not tend to leak as easily over time.

That's my understanding.

[Btmonty2]

you also get better gas milage. I have a V8 and I'm currently getting around 18.5 city mpg...I have gone on a long trip yet

[CruznSS]

Dealership charges $59 to replace air with nitrogen. Might not tell a difference. It will extend life of tire if your the type that forgets to check tire pressures. The dealership will check & refill for free as needed.

Sent from my PC36100 using Tapatalk

[Btmonty2]

mine cost 40 bucks,,,, and they will refill for life of my car....even when I get new tires

[Dr_Doom]

I run Goodyears on my truck and at my last tire rotation, I asked the Goodyear people about nitrogen and he told me that unless the tire was designed and tested to run with nitrogen, that I shouldn't use it. He said it could cause uneven tire wear because some of the materials in certain model tires shrink and expand in varying temperatures and it was made and designed to react with how air volume responded with temperature swings.

I dont know if that was a sales pitch or not, but the answer he gave when telling it seemed to me like he had been well informed (whether its factual or not) priorly about the subject and I didnt get the impression he was making it up on the spot.

[Keith.M]

I think it's mostly about the molecule size of Nitrogen, in that you'll not experience the gradual loss of air pressure over time that is typical of radial tires now. Whatever gas you put in your tire, will be subjected to the effects of temperature change, whether the heat of driving or just sitting exposed to the high temps of a summer day on an asphalt surface. Not sure it's worth much of a premium expense, since the car has pressure monitoring, unless you don't have an easy method to inflate. Remember, you've no spare, so keep the 4 on the road properly inflated.....