Nitrogen filled tires

[Kirk W]

we were just looking at new cars in Las Vegas and every car we looked at had nitrogen in the tires at a cost of 195.00 add on ouch!

That is what they call a "dealer add on" and like the special paint coatings and upholstery treatments they are a very high markup items. An example of this was an upholstery treatment system being sold at the WY Auto Dealer's Convention when we were there that sold to the dealers for $20/auto, took about 30 minutes to apply, and which had a suggested retail price of $189, back in the 80's. The same company also offered special treatments for paint and other things automotive. I'd bet the nitrogen for tires is just another such item with very similar wholesale/retail relationship.

[Jimalberta]

Bottled nitrogen is not that expensive ...these dealers are making huge profits from this.

[Mark and Dale Bruss]

 

Bottled nitrogen is not that expensive .

It is worst, most use a compressor with a filter to get their Nitrogen from the air.

[Ray,IN]

Off-topic, but related. Menards stores have a FINI brand, 150psi air compressor on sale for $89 right now.

[mscans]

Keeps moisture out of tires. Only benefit i am aware of

I agree with Glenn. The nitrogen refiner systems require dry air to work properly so that is the real benefit of using a nitrogen fill, oh yeah, money in the dealer's pocket. a VERY minor side affect is reduction in oxidation from inside the tire but don't see that as anything we have to worry about

[jadatis]

Made a document about that filling with normal air is even better then to fill with Nitrogen.

Will give copy of it here.

Someone wrote about Argon filling , and I also thought that it mayby even would not difuse trough the tire at all because its a nobel gas.

But putting this on Dutch Science forum gave me the information that difusion speed is in between Nitrogen and Oxigen.

At the moment my conclusion is next

Nitrogen ( N2 ) diffusion speed 1 78% or normal outside air

Oxigen ( O2) diff sp 3 21% of normal outside air

Argon ( AR) dif speed about 2 1% of normal outside air

residu CO2 H2O etc

 

Here the document copy

 

Filling car tires with normal air is better then with Nitrogen.

A. Oxygen, which makes 21% of normal outside air, in volume absorbs more energy to rise a degree in temperature then Nitrogen.

Difference is only 1% , but in selling argument is sometimes mentioned in energy/ mass so Joule/kg.degr. Kelvin and there Nitrogen wins by 13 % . Tires though are filled with a certain volume so that counts .

This selling argument can be de-myth simply by the fact that its untrue.

 

B. Water in a tire transports the heat more then dry air or Nitrogen-filling ( which is by its production process free of water).

Not for no reason water is used in central heating and cooling system of cars as main substance.

The tire inside will have lower temperature which is better for cooling down the important spots of the tire wich have to keep a low enough temperature to prevent hardening and damage in next bending of those parts.

When incidentally the tire inside gets hotter ( sunshine on tire or severe braking, or high ambient temperature) more water goes over to gas wich highens the pressure inside the tire more then dry gas. Also then more water as gas in tire so even better cooling.

So advantage of water is 2 ways when needed, better cooling and lesser heat production.

Disadvantages of water as oxidation only happen at outside . Tire specialists will confirm that when they remove a tire of the rim , the rim inside the tire is not corroded.

 

C. When a Truck, transporting flammable substance, is on fire, the little oxygen in a tire will , when exploding ,probably even kill the fire .

In tunnels experiments where done to kill the fire with air current , and it worked, despite the oxygen in it.

 

D. A normal car tire up to truck tire is not a race-car tire, for which a constant as high as possible contact area, so best grip , is needed to give half a second better round time.

For that reason they are filled with as dry as possible air or Nitrogen.

That this gives low lifetime is not important, and for a normal car tire it is.

Often blowing tires at racing, is seen there as collateral damage, but we don’t want that for normal car tires.

 

E. A car tire is also not a airplane- tire in which the water can freeze and when landing this can give misbalance , which can lead to tire-failure or accident, when suddenly going from zero to about 200m/h.

The water in a car tire does not freeze that often, and when it does and the car begins do drive , it begins slow and the misbalance is not a big problem . then pretty soon, certainly when on speed the ice is melted to water and problem will be gone.

 

F. When filled with normal air the user is aware of checking the tires regularly, which takes better care of a saver tire, because regularly filled up to the right pressure and optical checking of the tire .

The illusion that Nitrogen filling makes the tire to loose almost no pressure, which is often exaggerated to 5 times , while in real a poor 2 times and then only in the very beginning, makes the user less caring .

The tire also looses air when hitting pavement so temporary leak between edge of tire and rim, Filling with whatever gas-combination won’t prevent that.

This idea is even stronger when TMPS is used which is often inaccurate , so the user thinks to maintain the right pressure, while really riding with to low pressure for longer time, which can lead to tire damage. Aftermarket sensors for TMPS when screwed on the valve can give leakage trough hole where valve is placed , because of the bending of the valve by centrifugal forces at speed.

 

G. Filling with normal air is always possible, even with a bicycle- pump, is only to fill up so won’t take that long. When you keep driving with to low pressure , in order to find a place to fill with Nitrogen, you damage your tires. So just fill up with normal outside air, even when the tire is filled with Nitrogen. Then also you don’t need to have the tire refilled with pure Nitrogen by your tire specialist when at home again, not worth the trouble, and normal air is even better then nitrogen because of the water in it.

 

 

 

 

[Jimalberta]

I'm thinking if I filled my tires with helium the whole rig would be lighter on the road and would save me some fuel costs.

[GlennWest]

lol

[reed and elaine]

RayN - As you note, the tires have air at standard pressure when filled with N2 ( P = 101.325 kPa = 2116.2 lb_f/ft² = 14.696 lb_f/in²) and they would be filled to perhaps 90 PSI over atmospheric so they would still have 1/6th air. It would be possible to purge the air from a tire but it would take a long time and a heck of a lot of N2.

 

I doubt that the N2 used to fill tires has been water purged.

 

Argon, love the idea, no further advantage and one heck of a lot more expensive.

 

Reed and Elaine

[Chris-n-Dennis]

I sincerely hope y'all realize I was typing tongue in cheek about the argon gas. It was meant to point out the same "logical" sounding but non scientific reasoning for alternative gasses. ( I may have been serious about the used paperclips though)

 

Argon, love the idea, no further advantage and one heck of a lot more expensive.

 

Reed and Elaine

[FastEagle]

OEM trailer tire fitments filled with nitrogen will normally have green valve stem caps. See PIX below. Looks a little underinflated so the new owner can start right out putting air in it.

 

http://www.irv2.com/photopost/showfull.php?photo=27423

 

FastEagle

[mscans]

 

I doubt that the N2 used to fill tires has been water purged.

 

 

Reed and Elaine

 

The Nitrogen separators require that the air be dry before the process so ALL the N2 from these machines is dry, probably the best part of the process as far as tires are concerned.