I recently purchased a new Honda and the dealer asked me if I wanted nitrogen in the tires, which I declined. Is there anything to this or is it just hot air?

Nothing to it, OK if it’s free. Search ‘nitrogen’, you’ll find dozens of discussions.

The atmosphere is 78% nitrogen, so your tires already have nitrogen in them.

Did you accept the ScotchGuard fabric protector and Armour Glaze paint and finish protection?? Did they offer undercoating?

Its another way to squeeze just a few more dollars out of you before you make it out the door. You know, there are people in this country who get paid to do nothing but sit around and think up gimmicks like this.

IF its free, the idea is to give you that warm fuzzy feeling that you got extra value for your money.

Seriously, though, I think the concept is that nitrogen molecules are larger than oxygen molecules and therefore won’t pass through the rubber as easily, meaning the tires should hold their pressure longer (in theory). However, as Jeffmw05 stated, plain old air is already mostly nitrogen.

There is an advantage to 100% nitrogen fills. It is dry and it’s expansion due to temperature changes is a little less, but except for race car drivers and jet air craft, it is not worth the bother. It is just another sales gimmick.

Did you mean to say “there is NO advantage to 100% nitrogen fills”?
I agree.

Besides, having those little green caps on my valves makes me feel like a target for scam artists.

i got the free nitrogen when i bought my michelins at Costco, but my running comment when asked is that i prefer the 80% nitrogen that i get for free. and when you think about it, the tire when mounted already has straight air in it so even when they fill it with pure nitrogen, it’s not going to end up at 100%, so yeah it’s really not something one would ever want to pay for.

First, there is no way to get 100% nitrogen in. You can’t pump all the air out of the tire before filling with nitrogen. So, maybe you could get 90% nitrogen. After a week, it will be down to 80% nitrogen.

I run nitrous oxide in my tires. Never know when you need a good laugh.


Or a big explosion…

Pure nitrogen is heavier than air. Therefore if your tires are full of it, you have more unsprung mass, giving you inferior ride quality, and more rotating mass, decreasing your fuel economy.

(Just not enough to notice.)

Well, actually nitrogen is slightly lighter than oxygen (28 vs. 32), so the opposite is true.

How about calcium chloride mixture for your tires…you’ll have to stay under 10 mph, beef up your suspension dramatically and use inner tubes, but oh the traction.

Calcium chloride … LOL!

The only time pure nitrogen fill is beneficial is in high heat climates like the south & southwest where the inert gas will allow full inflation of the tire rather than having to run them 5-10 psig under to keep them from breaking cords/blowing out via the pressure increase from operational heating. Rough figure is 1psig increase per every 10?F increase in tire temp. Thus, a 16" LT tire inflated to 80psig at 70?F will show roughly 91psig when it’s at the 180?F operating temperature running down a hot road under load. One of the most common tire failures in the southeast is from overpressure caused by operational heating - compressed high humidity air does not loose all its water content before it gets in the tire and the amount of pressure increase on heating is increased proportional to the moisture content of the air put in the tire.

Tardis is also correct, unless the tires are being pulled down on vacuum, they already contain a given amount of ambient air that is not displaced by nitrogen.

Air and pure nitrogen behave exactly the same with respect to temperature. Both are ideal gases at these temperatures and pressures. No difference.

While the heat results in more blowouts, it’s usually because of underinflated tires overheating and failing, not overinflated tires bursting.

BS alert…Nitrogen expands with heat at almost the exact same rate as oxygen…Tires are DESIGNED to accommodate the normal heating that occurs with driving…

The bicycle I had when I was a kid had 26 x 2.125 balloon tires. I think I was supposed to use helium in these balloon tires. The bicycle was a Western Flyer (sold by Western Auto), so I assume that helium in the tires would really make the bicycle fly.

No it’s not. Its very slightly lighter than air

Check out These guys know what they are talking about.

I like the picture of somebody sucking the air out of the tire before filling it with nitrogen. This gets rid of the oxygen that was in there but damages the tire in the process.