Nitrogen in Tires

Ha ha ha ha.

Unless you are flying a plane, forget it.

Hammo

Quite a lot, IIRC from a thread some months ago. Google could be your friend, if you'd let it.

There have been numerous discussions about this. Conclusion: It won't hurt, but you'd be nuts to pay for it. Who's trying to sell it in your area? Pep Boys?

Good morning. I know nitrogen is injected into those one cup coffee servings to help keep the coffee grounds fresh. The plastic container and foil lid wouldn't hold up to a vacuum seal. It's not the answer you're looking for I know, but I wanted to give you one example where it's benefit is undisputable. mark_

Used in racing all the time; helps keep pressures consistent in spite of extreme temp changes.

I don't think you have to worry about the same extreme conditions in you passenger vehicle so I'm not too sure what you will gain.

What do you expect to gain?

The nitrogen molecules are larger than O2, so tires supposedly loose pressure from leaks much slower with pure nitrogen. Depends on how much more it costs as to whether it is worth it.

I bought my own compressor...I don't care! ;)

If they're doing it for free as part of their normal service, can't hurt and may help with tire longevity on cars that don't get driven a lot - where the tires rot out before they wear out.

If they charge for it, or that shop charges more than the guys down the street for the same tires, forget about it. It's supposed to be an added draw to get customers, not an added profit center.

Getting the Oxygen (21%) out of the air they use in the tires does keep the pressure constant in the tires and they don't leak down as fast (Oxygen molecules are smaller and get through the gaps in the rubber easier) and the inside rubber lining of the tire doesn't deteriorate over long periods of time. But IMHO the effects are minor.

The only place you /have/ to use Nitrogen is on aircraft and specialty tires that run at ultra high pressures and go up to high altitudes. Airplane tires run at 300 PSI on the ground, and when you add in the reduced pressure at 40,000 feet...

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Digression time? Fair point, though I'm not sure the numbers are too scary. At ground level, air pressure is around 15psi. Would

300psi not be pressure in excess of that? Thus absolute pressure is only 315psi, which is the value to use when (say) at such high altitude that you may as well be out in airless space. What does concern me is what happens when a plane enacts an emergency stop: colossal temperatures are built up in the nearby wheel hubs (such that the brakes glow pink-white -- as in a TV documentary series, about the design and building of the Boeing 777, which showed the _extremely_ stressful emergency braking test). Flammability then is acutely interesting. Carrying a load of diluted oxidiser in a neat presurised package next to such a hot mass is a tad naughty.

The idea about paying for it may have come from another thread from last summer, IIRC. I believe someone mentioned that Pep Boys were charging for nitrogen as if it were an accessory.

If you mean free nitrogen, why not? The question is would you spend money to get 100% nitrogen inside of your tires, rather than the 87% nitrogen that is OUTSIDE your tires and in the compressed air inside of your tires? ;)

mike

Costco put nitrogen in the Cross-terrains for our Highlander and at 45k, wear is good and pressure always good (less than a pound or so at 6 months) Also put it in the MXV4's on the Avalon, figured it was free with the rotate & balance (OEM's not Costco tires).

Seems as if in previous discussion someone talked about NASCAR drivers using it too? Ron

Even if true, air is already 80% Nitrogen. Becasue of changes in avarage temperature, if you maintain your tires properly, you will be adding air frequently (or letting some out possibly) wheter the O2 leaks out faster or not. The difference is trivial.

Ed

Once again - "ordinary air" is already 80% Nitrogen.

Ed

It helps extend the life of the tires, and helps keep the pressure stable.

Costco provides it at no extra charge when you get tires there.

I see the tell-tale green valve caps on probably about 1/4 of vehicles now. Around here, Costco is the biggest tire retailer by far.

Hahahahaha, thanks for the laugh!

I use only nitrogen-13 in my tires and have to reinflate them every couple of minutes.

One tire dealer here advertises that they use "hybrid" nitrogen, which I take to mean regular 78% nitrogen, 20% oxygen air.

Again, nitro is used in racing because the gas is inherently less reactive and more predictable to changes in temperature. NASCAR stock cars can start out with pressures as low as 10PSI and by the time the tires are at full operating temp the pressures can be 3 - 4 times that. Nitrogen, being more stable, is more predictable so crew chiefs can set up the handling characteristics of the car knowing more accurately how the tire pressure is going to change during that run. For example the car may be set up loose (over steer) for the beginning of the run, knowing that by the end of the run the built up tire pressures will tighten the car up. In a sport where making 1/2 PSI changes to the tires can completely change the handling characteristics using a more predicable gas to fill those tires is vitally important.

Some have mentioned the larger molecule means less slow leaking but I'm skeptical with that reasoning. It may be true that the molecules are larger but I suspect that if you have a leak it will leak just as quickly as normal air.

Some others have mentions that regular air is 80% nitrogen and that is true but as I said, in racing, where 1/2 PSI can make the difference between a good handling or poor handling car, 20% O2 can make a huge difference in the tires performance.

So w/ that in mind I can see nitrogen in use for a passenger car where temperature changes are extreme, but under normal operating conditions in normal weather situations I don't see a need. That is unless you think your going to turn left for 3 hours at 180 mph.

Many time in the past 20 years, the AAA has said that 60% of cars have underinflated tires. Perhaps nitrogen's not such a bad idea, especially for drivers who think their tires only need to be checked at each oil change, which might be just once or twice a year. Driving defects are often due to a combination of factors (incompetence, blindness, drunkenness, cell phone, screaming children, stupidity, death of driver). Any edge is a good thing.