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So I have a 2011 Dodge Challenger R/T… I bought the car with purely filled Nitrogen Air filled tires, and have been reading reports on its “benefits.” I want to keep my tires inflated to the proper psi, shops are charging 35 dollars here in florida to refill them. I heard mixing the gases won’t harm the tire initially, but will decrease it’s Nitrogen effective properties until just air is leftover.
I called up a “Tires Plus Store” and the employee told me that they do not service nitrogen because “A study ” has shown that the benefits are almost nil, and that its just a gimmick. Especially here in florida’s climate…
What are your thoughts on this?
I’m thinking about just scraping the nitro, and going with air, since I have my own compressor anyways.. :unsure:
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The theory of nitrogen filled tires kinda goes like this: Nitrogen is an inert gas that is only one element. Air is made up of multiple elements that will expand and contract at different rates and are prone to more expansion and contraction in general. To reap the slight benifits of nitrogen, all the air has to be purged from the tires and be filled with 100% nitrogen. That’s how I understand it anyways.
A friend in the Air Force said the aircraft tires are filled with N2, but I do not remember the reasons behind it.
One benefit of nitrogen is that it’s fairly inert and does not react with wheels or tire. Oxygen is a good oxidizer and may cause oxidation of the metal wheel or the material in the tire. Also, oxygen may be a concern when combustion or explosion hazards are present. Although I don’t know if oxygen is a major problem for tires in most auto applications, but I think/hope N2 would be more available if it was a problem.
Also, most compressed nitrogen is mostly dry and does not contain a significant amount water vapor. The water vapor can promote corrosion on steel. It might also create a problem condenses and freezes. A dryer can be used with the compressor to remove the water vapor.
I use plain ol’ air myself.
[quote=”Hanneman” post=114509]A friend in the Air Force said the aircraft tires are filled with N2, but I do not remember the reasons behind it.[/quote]
Yep, and commercial airlines as well. The main reason is that aircraft tires are inflated to very high pressures (around 200PSI for a jetliner and 340PSI for the Space Shuttle) and they experience a great deal of thermal cycling. Freezing at high altitude and boiling when they touch the runway. Not to mention, that oxygen (when compressed to that level) becomes a credible explosive hazard.[quote=”Hanneman” post=114509]
Also, most compressed nitrogen is mostly dry and does not contain a significant amount water vapor. The water vapor can promote corrosion on steel. It might also create a problem condenses and freezes. A dryer can be used with the compressor to remove the water vapor.
[/quote]DING! We have a winner! The dryness of GN2 is what provides the greatest performance benefit over regular air. Dirty compressor air is typically saturated in water, and can contain a fair amount of pump oil. If you inflate your tires from a CDA (clean dry air) source, then the difference becomes negligible.
Outstanding answer Hanneman!
The air we all breathe is mostly nitrogen I think it is 80%? I agree with the other tire shop in that nitrogen filling the tires is pretty much a scam.
[quote=”McWicked” post=114547] The dryness of GN2 is what provides the greatest performance benefit over regular air. Dirty compressor air is typically saturated in water, and can contain a fair amount of pump oil. If you inflate your tires from a CDA (clean dry air) source, then the difference becomes negligible. [/quote]
I guess I should replace the drying agent on my compressor in the near future.
[quote=”brokemechanic3000″ post=114549]The air we all breathe is mostly nitrogen I think it is 80%? I agree with the other tire shop in that nitrogen filling the tires is pretty much a scam.[/quote]
It’s about 78% N2 (I know, splitting hairs – or decimal places), 21% O2, and the rest is composed of the noble gases, methane, CO2, and water vapor. I remember reading that every breathe you take contains a gas molecule from Julius Caesar’s last breath.
Shops have all kinds of scams for draining your wallet.
The air is mostly nitrogen so pretty much all tires are filled with nitrogen anyways.Plain ol air has worked just fine in tires for over 100 years and now it isn’t good enough?
The moisture? Well you know, rims are constantly rusting through.Nitrogen MIGHT have benefits but not enough to justify the $10 per tire they want to charge.
Personally on domestic cars I don’t think it’s worth it.
In other applications it have more significant benafits. For example.
If a military vehicle is taken from the UK after just been serviced placed on a ship and taken on a 4 week exercise to Norway where the tempeture is -20 C the pressure in the tyre will significantly decrease as the air in the tyre decreases, if the driver checks the tyre he fills it up to the correct pressure.
He drives the vehicle back onto the ship a week later where the tempeture is +15 C and the pressure over inflated.
However, tyre pressures are often reduced for driving on snow and rough terrain anyway, so it can also be argued that in this case air is better than Nitrogen.
As for my car, I’ll never concern myself with nitrogen filled tyres, at best if I want to keep an eye on my tyre pressure and I’m too lazy to check it regularly I might invest in those valve caps that show green for +30PSI and Red for -30PSI.
Has anybody ever tried them? I haven’t but have seen them, if they work I’d say they are a better investment than Nitrogen.
Given that they would give an early indication of a puncture especially.
Kerb
Here’s a link
Tyre pressure indicator valve caps
[quote=”brokemechanic3000″ post=114549]The air we all breathe is mostly nitrogen I think it is 80%? I agree with the other tire shop in that nitrogen filling the tires is pretty much a scam.[/quote]
One shop I worked at had a stand alone Nitrogen “compressor” with a gauge showing the percentage of Nitrogen. It was usually 81-85% on a good day. We charged $5 a tire, but that included free air ups. On the one hand yes, it is a way to increase the per customer income. I have also heard some not necessarily scientific evidence from some car guys that you will get ever slightly better gas mileage.
The idea is that nitrogen molecules are larger and tend to not change the pressure as much as the temperature changes. If you log serious mileage, it might be worth the increase. Some transportation fleets use it, the rest of us would likely not see the benefit.
If we really want to increase mileage we then should fill our tires with helium thus making them lighter.
Very good video from 5th Gear on the subject. (I do like their shows).
There are quite few good articles around suggesting to people to just check their tire pressures regularly and don’t waste your money on nitrogen fills.
You are not running a race car but a road car so you do not need it.(Just buy a good tire gauge which will not set you back more than $15 and last you for more than 20 years).
In any event you are eventually going to have to stick normal air in one or more of your tires at some stage because nitrogen will not be available when you need it thus negating the benefits – as will an impure nitrogen fill which most of them will be because of dubious quality control at the filling stations.
In any event one of the better articles on the subject is here and published on the tirerack site
http://www.tirerack.com/tires/tiretech/techpage.jsp?techid=191
For those of you comfortable with wading through scientific literature, here’s a study conducted by the U.S. Department of Transportation National Highway Traffic Safety Administration:
http://www.nhtsa.gov/DOT/NHTSA/NRD/Multimedia/PDFs/Crash%20Avoidance/2009/811094.pdf
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