just noticed that the caps on the tire stems are labeled "N2". Do they fill with nitrogen?

 

but if the air we breath is 80% nitrogen...

 

yeah I know - I've read many debates about N2. Never saw the need.

Just wondering if they were indeed filled with N2 from factory

what's strange is that I happened to look at the tire pressures in the MID several times and the pressure had changed about 5psi from one time to the next
I thought N2 was supposed to minimize the change

 

I thought the same thing with nitrogen filled tires. My pressure raises as I drive from starting 32 and raises to 34 35 sometimes.

 

With Nitrogen the pressure will still raise with heat but to a lessor amount than air which has oxygen in addition to nitrogen. Nitrogen has a lower coefficient of thermal expansion. But I think one of the main reasons for using N2 is that it is normally dry nitrogen. Air has moisture which can contribute to tire rot and may also lead to rust on TPMS sensors. But of course who is going to keep the tires inflated only with dry nitrogen? Not sure where I would go to get it. I have a pump at home that I top up the tire with and in Houston there is guaranteed to be a lot of moisture in that air!

 

^im loving the weather this week!!
please, humidity, dont return!

 

Not from factory - dealer dependant. Some do, some don't. Hit a landscaping rock on I-45, blew tire and damaged the wheel. Dealer that repaired did not offer N2 as an option. So I have 3 with N2, one with air. All tires still have the same amount of fluctuation once tires warm up - makes me wonder if selling dealer actually put N2 in tires.

 

so if Dealer puts N2 in tires they change the stem caps?

 

Yes, mine are green on top.

 

I've had nitrogen-filled tires several times, and I found zero difference between it and plain air. Pressures increased 4 or 5 pounds with both after 10 minutes of driving.

And the first time you have to top up your tires the already-diluted nitrogen is diluted further anyway.

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