jrv2000

So i roll up to costco, and i see a sign that says...

NITROGEN FILLED TIRES....BETTER HANDLING...BETTER GAS MILEAGE...ETC

now how can you even justify paying 40 to get your tires filled up with nitrogen? How are people on this earth sooooo stupid that they actually believe something of this nature will actually do something worthwhile. Is there any sort of proof/evidence that might suggest it is better than air? Please enlighten me.

John

trench

thats what I heard. I can get all four done for 10 bucks here.

DuMa

its a new fangled thing. but what happens if your tire is low on psi, how are u gonna fill it up? theres no gas stations that offer nitrogen fillups

LED-Maniac

I heard that the N2 will actually eat your tires up.....but then again thats just a rumor.

jrv2000

but how is nitrogen suppost to be beneficial? All it is, is a gas like air that keeps aour tires inflated. Why is one type of gas better than the other?

John

REaL

I heard about this on motorweek on the speed channel and they said it really does work. "When you put nitrogen in your tires then your tire pressure remains constant."

Heres an article about it: http://www.waff.com/Global/story.asp...7&nav=17jVRjuL

GammaTNT

iTrader: (8)

There are nitrogen around us in air, and outside of the tire. So N2 will not eat up tire. The only benefic i heard is they don't change pressure that much when the tempture change.

ricerocketdave

Ok the real benefit from using the nitrogen is that the molecules are quite a bit bigger than regular oxygen molecules and in turn will not seep out of your tires over time. Where the oxygen molecules will seep out. Also the nitrogen will not expand or contract while being hot or cold, so your tire pressures remain the same all the time. I have had nitrogen in my car for almost a year now and have not dropped in pressure at all. It is definitely worth the 40 dollars to get them filled. The only way that you will need a refill is if your tire would get punctured from a nail or something.

Hope this helps

djct_watt

yes. . . the air that we breathe is mostly composed of nitrogen. . . pure nitrogen would be less sensitive to changes in temperature than the the oxgen, nitrogen, and other crappy gas mix that exists in our air. . . but is it worth $40. . . dunno bout that.

TheKnown

dude, im just going to fill them rubbers up with helium, cause my tC is straight up flying

trench

trench

I asked my father-n-law about this. He has been a mechanic for over 30 years. He also works on Military jets now. anyway, check out this article on Nitrogen for jet plane tires.

http://www.physlink.com/Education/AskExperts/ae192.cfm

Dont remember where I found this! But, I put it in quotes.

Somnambulated

Sounds good to me... But I'll wait until I see it for $10 instead of $40!

Just remember... Don't put liquid nitrogen in your tires...

tC_302

Interesting!

superjeer

I can't remember the number, but our air is overwhelmingly mostly nitrogen (80% maybe?). so, if the smaller crap leaks out, then over time refilling your tires as they drop in pressure will eventually leave your tires with all nitrogen (as the limit of fill ups reaches infinity the presence of smaller molecules like oxygen goes to 0, simple calculus.).

X + (100-X)*80% = X where X starts at 80. So after one refill, you’re at 96% N2, After a second you’re already at 99.2% N2. So, I’d say $10 or $40 for a fill up of N2 is a waste.

Nitrogen N2 78.084%
Oxygen O2 20.947%
total 99.998%

superjeer

George will chime in with the real formula shortly, since I can't remember math notation anymore.

(pseudo code below)

double ntwo, n = .78084;
double target = .999;
int count = 0;
while(n<target) {
n=n+((100.0-n)*ntwo);
count++;
}
out.println(Integer(count).toString());

niguels

I agree that using nitrogen keeps the tires free from moisture.

The inmediate benefit is that with the moisture out , there is less mass of gases in the tire (N2 mass + H2O mass) therefore reducing heat build up.

This means that a tire filled with regular air is more likely to overheat due to temperature and friction than one filled just with nitrogen that, by the way, will come dry off of the bottle due to the particularities of the bottling process (cryogenic process).

Regular air for tires is obtained from air compressors. Is a fact that the air we breathe contains moisture, or water, that if is not removed will make its way up to the tires. Also air compressors work with oil, so if no actions are taken oil will also make its way to the tire. Nobody knows the operation conditions of air compressors at gas stations or how are they maintained. To find good quality air is a lottery unless we know facts about a particular gas station compressor.

In a manufacturing environment, every time I install a piece of machinery that needs dry and clean air, I make myself sure to install an oil remover (coalescent filter) and an air dryer before the comsuption point.

Now, I have to clarify from an engineering standpoint that IS NOT TRUE that nitrogen will not change its volume with the temperature.

Nitrogen, as any other gas, behaves according the IDEAL GAS LAW, and IT DOES CHANGE its PRESSURE according to the TEMPERATURE and MASS existing in the container (tire). The equation that governs the pressure/volume/temperature changes is PV=nRT. It can be found in any thermodynamics book.

Probably what the people may perceive as no pressure change is that proportionally, for the same temperature differential, the pressure change for the air is greater than for nitrogen.

Just my 2 cents

QUESTION: I would like to know if there are any other Mechanical Engineers at ScionLife or this forum - thanks

LucidBD

i work at costco in my area. i do not work in the tire center but i do about what goes on and what we offer out there. when my tC comes in i will be putting nitrogen in my tires from what i have heard from the manager out there. nothing but good things. yes it might be $40, but if u can get it from costco its about $10 cheaper than anywhere else. ill ask at work and see what i can find out

niguels

Also, the molecular size does not play any rol in how fast a tire losses air. It is a sealability issue. The tire mounter must be sure to apply sealing compound to the lip of the tire before it is inflated to prevent leaks.

Is pretty difficult to separate air components at ambient temparatures. There is no such a thing like that oxigen will escape before the nitrogen if there is a leak. It takes about -300˚F / -185˚C to separate the air components trough a cryogenic process. There are also non-cryogenics processes that require special materials to reach the same goal. For more information check the link.

http://www.uigi.com/compair.html

Lonely_Raven

Awesome info in this thread!

But niguels pretty much shot down all the advantage points
I've read about.

Would you use nitrogen niguels?