Nitrogen in Tires

[John M.]

What are thoughts on replacing the air in our Corvette (or any) tires with Nitrogen? I've read the benefits, but I can also see the need for a readily available, like in the garage, nitrogen supply to adjust tire pressure to changing outside temperatures or when over-inflating for winter storage for those of us up here in the frozen tundra.

Does Nitrogen expand and contract with outside air temperature changes and internal tire generated heat changes the same as air in a tire does?

Save the Wave ....... JGM

[Jack H.]

Re: Nitrogen in Tires

If memory serves, the definition of air is:

"A colorless, odorless, tasteless, gaseous mixture, mainly nitrogen (approximately 78 percent) and oxygen (approximately 21 percent) with lesser amounts of argon, carbon dioxide, hydrogen, neon, helium, and other gases."

Therefore, air is primarily nitrogen and one would expect pure nitrogen to behave quite similarly to air in terms of expansion/contraction....

[Terry M.]

Re: Nitrogen in Tires

Nitrogen in automobile tires is pure marketing with a goal of making money for the marketer, and relieving the consumer of money.
You asked for an opinion -- this is mine.

[Bill M.]

Re: Nitrogen in Tires

John
We used nitrogen in our racing go cart tires. the benifit was that they did not grow as the tires got hotter. When a tire grows it changes the handeling of a race car.Nitrogen has no humity in it and the humidity is what causes the tire to expand.
Bill

[Donald T.]

Re: Nitrogen in Tires

The other problem is removing the air that is already in the tire. Even if you deflate the tire, there will still be a significant amount of air that will be left. Air is mostly Nitrogen to begin with, so at best you might be able to slightly increase the % of Nitrogen in the tire. Not really worth the time and effort for a street car.

[Duke W.]

Re: Nitrogen in Tires

It's BS! Check the archives. There was a discussion a year or two ago that laid out the real science and the junk science behind the nitrogen scam.

"Humidity" i.e. water vapor - H2O in the gas state - behaves as an ideal gas - just like nitrogen, oxygen and the other trace gases in air.

The only issue is when the tire temperature drops to the dew point or below and water vapor condenses to liquid.

If you use reasonably dry air, it's not an issue.

Duke

[Bill M.]

Re: Nitrogen in Tires

Forgot to say that we used to pull a vacume on the tires to remove atmospheric pressure

[Joel F.]

Re: Nitrogen in Tires

As you know, the main benefit for non-performance applications is to prevent pressure loss as nitrogen particles molecules are marginally larger than air. My wife and I bought a car a new few months ago and the dealer had "installed" nitrogen in the tires of all new cars and added $30 to the price (I refused to pay the $30 but that is another story). Within only a few weeks the tires had all lost pressure. Glad I didn't pay that $30!

[Michael W.]

Re: Nitrogen in Tires

I think you guys are overlooking the benefits of modern science. I'm taking the day off work tomorrow to have a contractor flush out the water pipes in my house with Dihydrogen Monoxide. He's promised that his work will be so good that there'll be no trace he was ever there.

[Edward B.]

Re: Nitrogen in Tires

The main benefit seems to be the green caps on the valve stems. Wow!

[Kent K.]

Re: Nitrogen in Tires

The main benefit seems to be the green caps on the valve stems. Wow!

Green Caps provided are by our local COSTCO. If they use nitrogen in all tires they sell, I've never seen a nitrogen supply truck there.

[Paul O.]

Re: Nitrogen in Tires

John in the commercial aviation industry I work as a Aviation Maintenance Technician for the past 38 years. We use dry Nitrogen in all the aircraft tires. Aircraft tire are still made from natural rubbers so there maybe a slight difference compared to automotive tires also these tire are recapped several times over it life. But nitrogen help preserve and protected the rubber compounds from the elements also the pressure changes less over a wide temp range. So if the tire is hot or cold, hot about 200 deg F cold 0 deg F on most of the tires there is only about a 15 deg F difference when inflated properly. A 737 main tire cold is about 205 PSI hot 220 PSI. The tires do lose pressure over time most tires are not 100% sealed but in aviation it does make a difference aircraft operate is rapidly changing environment compared to a car. So the other gasses in normal compressed air would have a greater effect on aircraft tires then automotive tires that said nitrogen is a better product then normal compressed gas for the reasons stated above plus several more. For normal automotive tires this maybe a bit much but there is a tire store here in Cincinnati that if you buy tires from them the will service those tires with nitrogen at no cost for the life of the tire. So maybe for tires on a trailer queen nitrogen could be a good thing it may extend it life. Paul

[Michael W.]

Re: Nitrogen in Tires

If I were to believe all of the above, wouldn't the tires themselves act as the perfect filter and be effective solving their own faults? It has been stated that the reason for pressure loss in a tire is that the smaller oxygen molecules leak through, while the larger nitrogen molecules remain behind.

Doesn't that mean that eventually there will be no oxygen left inside the tire, only nitrogen? Each refill will introduce a smaller and smaller amount of oxygen while using a constant size filter (the tire) to allow it to escape.

This means that an old tire (never removed from the rim) should have a measurably higher amount of nitrogen inside, and exhibit a progressively reducing rate of pressure loss over the life of the tire.

I love it when problems solve themselves.

[Joe L.]

Re: Nitrogen in Tires

There are specialized applications (such as aviation and competitive racing) where pure nitrogen as an inflatant for tires may have some practical benefit. I believe that the A-12/SR-71 was the first aircraft to use nitrogen in its tires, but it operated at 100,000'+ altitudes and Mach 3.5 speeds. Later, the use of nitrogen expanded to other aircraft uses and, even later, to automotive uses.

The only "benefit" that I can see with pure nitrogen is that nitrogen, being a virtually "inert" gas, there is no danger of it reacting with and degrading the material the tire is manufactured from. With air, the oxygen it contains has the capability to oxidize and degrade materials it comes in contact with.

However, the amount of damage that could be caused to a passenger car tire over its life by the oxidizing affect of the oxygen present in air would be negligible and, for all practical purposes, not even worth considering. The expense and INCONVENIENCE of having to obtain pure nitrogen for maintaining tire pressure FAR, FAR outweighs any benefit in my opinion.

Besides, the outside of the tire would be exposed to air (and oxygen), anyway.

[Joe L.]

Re: Nitrogen in Tires

If I were to believe all of the above, wouldn't the tires themselves act as the perfect filter and be effective solving their own faults? It has been stated that the reason for pressure loss in a tire is that the smaller oxygen molecules leak through, while the larger nitrogen molecules remain behind.

Doesn't that mean that eventually there will be no oxygen left inside the tire, only nitrogen? Each refill will introduce a smaller and smaller amount of oxygen while using a constant size filter (the tire) to allow it to escape.

This means that an old tire (never removed from the rim) should have a measurably higher amount of nitrogen inside, and exhibit a progressively reducing rate of pressure loss over the life of the tire.

I love it when problems solve themselves.

Mike-----


Yes, and tires could just become a new way of manufacturing pure nitrogen. Generally, oxygen and nitrogen (and other trace gases) are produced cryogenically by liquifying and separating air into its component gases. Tires could become a new, more energy-efficient (i.e. "green") method for separating air into its component gases through what could be called a "molecular sieve" methodology.