Nitrogen in the tires

[Tarrngtn]

Does anyone know whether these self sealing tires are filled with nitrogen instead of air? My mechanical engineer buddy says nitrogen is better because it does not react with the rubber. But I thought perhaps these tires already have pure nitrogen. Also, I am concerned about whether it would hurt these tires to flatten them and then reinflate.

[EldRick]

The difference between 100% nitrogen and the 79% nitrogen you've already got is so trivial that only racers actually get an advantage from the practice.

Think of it this way: does the outside of a rubber tire need to be in 100% nitrogen?
Guess what - the outside is exposed to lots more oxygen than the inside, because the trivial amount of ozone on the inside gets absorbed by reacting and then it stops, while the outside is constantly bathed in fresh oxygen and reactive ozone, and UV radiation besides.

Don't waste your time or money - any advantage of nitrogen-fill is so small as to be theoretical and unmeasurable in actual use, particularly in a car that is limited to 93mph. (For my [theoretical] 200mph Tesla Roadster I'd insist on nitrogen...)

[Collimare]

I change all my tires to Nitrogen just to keep the pressure sensors happy year round. Less pressure change with temperature changes including extended hard fast running. Will maintain pressure over a longer period. I go years on my Airstream before needing to add.

[SeanNelson]

I change all my tires to Nitrogen just to keep the pressure sensors happy year round. Less pressure change with temperature changes including extended hard fast running. Will maintain pressure over a longer period. I go years on my Airstream before needing to add.

The dealer put nitrogen in my tires as part of the pre-delivery prep, but I swapped out the front tires for snows shortly after buying the car and they were filed with good ol' fashioned air. I've been monitoring the pressures via the TPMS system and so far I haven't seen any notable differences between the two pairs, even during long freeway runs.

[drfoto]

My wife's BMW X3 shows constant warning messages as soon as the weather turns cold if the tires contain air. Filled with nitrogen (free at Costco) the problem goes away entirely. The sensitivity of the system may vary by manufacturer, but in my experience is not theoretical at all with a sensitive tire pressure system.

[EldRick]

"Less pressure change with temperature changes..."

Not true. See Boyle's Law for further information.

[PackardV8]

Agree; nitrogen in tires is akin to religion. Some have faith in it not supported by any physical fact.

jack vines

[gpsman]

The reason nascar and airlines use nitrogen is more simple than you think.

The cylinders contain up to 2500 psi.
Want to fill a tire FAST?
Use higher pressure.

Also- you don’t need electricity (aka compressor).
You can fill tires “anywhere”.

It has nothing to do with chemistry.
It has nothing to do with keeping better pressure.

N2 cylinders are dryer than regular non-dried compressed air, but it is not difficult or expensive to make dried compressed air.

In NASCAR, IF a car came in with literally burning rubber, (about 1000 times more likely than in your car) the nitrogen will slow the burning, not enhance the burning, and if done while refilling COULD help suppress the fire. But this is not WHY they do it.

They do it because the high pressure fills quicker, and the cyclinders are portable and do not require electricity.

[EldRick]

Nitrogen inflation is a harmless way to separate you from a few dollars at the tire shop, but lightening your wallet is the only performance-related effect.
A better use of the money would be tipping the installer in advance, to not scar the wheels or the bead and get a good balancing job.

[SeanNelson]

...because the high pressure fills quicker...

I'm not getting the connection between high pressure and nitrogen here. I use high pressure (3000psi) tanks for diving, and they contain regular old air. You don't need nitrogen to get high pressure.