BearKiller

A fool and his dollars will soon part, one way or another; I might as well have his money as someone else. I provided the service he wanted.

And yes, he stood by his car while the work was performed; so we hoisted the tires clear of the floor, pulled the cores, and put in clean, fresh, slightly humid, Kentucky compressed air.

phox_mulder

Not normally a problem, as not many people cross the equator during a normal day,
ever notice how many tire stores there are on both sides of the equator though,
they're there for a reason.


phox

Geico266

That's why you see alot of cars backing up down there!

Mexstan

You are wrong about this. The two cancel each other out and that means the tire cannot spin. You need a conveyor to verify this.

Pop-Pop

Now, let's see. After I spend $ getting my tires nitrogened (nor aired) up and some knucklehead puts air in to get the pressure right, will this throw my suspension out of whack and cause me to go side-ways down the highway?

Wish I had all this knowledge when I taught thermodynamics back in college.

By the way, nitrogen isn't inert and to the best of my knowledge, PV=nRT is still valid. In a tire everything is constant except for pressure and temperature so, you can say, P=RT. That means if the temperature goes up, so goes the pressure.

WINDYR has it exactly right!

Geico266

Well, another myth busted right here at DTR.

Thanks Pop Pop! Or should I say proffessor diesel?

We occasionally get involved in phyisics & stuff.......

Do you know anthing about airplanes & conveyors?

LonestarCTD

The ONLY advantage that anyone would have putting nitrogen into their tires is that it DOESN'T migrate out through the rubber like plain compressed air. It's not all that much of a difference as Geico pointed out, but over time (an average light truck/passenger tire will lose around 1-2 psi per month) a tire will go low because of the loss of oxygen through the rubber. With pure nitrogen (and their are generators that will produce 99% pure nitrogen) you don't get almost any loss. It's being pushed by the industry because it takes alot of the responsibility that is usually entrusted in tire buyers to keep their tires inflated correctly and places it in the hands of the stores mounting the tires. That way, when a tire is low, it's low for a reason, not because someone didnt' check it in 2 years. The majority of people don't know that air escapes from their tires on a regular basis. They think that when it's aired up, it's gonna stay that way FOREVER, but that's just not true. The nitrogen won't really provide any other benefits other than keeping tires aired up to the pressures that are called for. With the new air pressure sensors in cars and trucks (2006 25% then 2007 100%) the industry is trying to keep people from constantly having their vehicles set off a low tire warning light unless there's really something wrong with the tire. And, even though nitrogen and oxygen are very close in size, the oxygen molecules in compressed air ARE able to permeate through the rubber in tires, nitrogen is just large enough to remain contained. At least that's what our trade magazines are pointing to as the chief reason for the change. I'll try to find the issues that had write-ups about it and try to post what I find here.

TurboTed

Features & Benefits

Does not diffuse as easily: nitrogen molecules are larger than oxygen, which means that it has a slower rate of pressure loss.?
Nitrogen permeates the tire at a rate of 30-40% slower than oxygen?
Inert gas: nitrogen disperses heat more quickly which results in cooler running tires?
Improved tread life
Reduced incidences of tire damage caused by excessive heat
Non-flammable; reduced chance of flash point explosion
Potential for better fuel mileage; if heat is restrained from building up the rolling resistance is reduced which can improve the vehicles fuel economy
Reduced pressure build up: maintaining pressure reduces the deflection, which again prevents heat build-up and reduces the chance of separation
Over-pressurization is as problematic as under-pressurization
Increased tire pressure above the recommended inflation point can reduce the contact patch and thus reduce the maximum possible grip levels.
Reduced moisture content introduced to the tire
Nitrogen is dry because of it's inert qualities. Many of the causes of failure in a tire can be attributed to moist air being introduced internally to the tire.
Moisture causes rusting, especially of the stem valve, increasing leakage. Additionally heating in tires is often caused by vaporization of the moisture

(Just more interesting info!)

Hipshot

ok.. ths is outa control.. I will relate this though.. we did have a lady come to our shop in a driving thunderstorm one day. The bays were full and she wanted us to check the air in her tires! no one wanted to get soaked so we told her... "sorry mam.... That's a chevy... that needs Sunoco air!' And she went their.. we got the call 10 min later.. hehhe....

rbuchana

Maybe I need a refresher on what an inert gas is, because I always thought they were the gases in the right column of the periodic table.

TurboTed

Noun 1. inert gas - any of the chemically inert gaseous elements of the helium group in the periodic table

windyr

Rbuchana
You are correct it is not an inert gas. This is why diesels have EGR. At high combustion temperatures nitrogen combines with 02 to form NOX, EPA says this is bad. If it was an inert gas it would not form NOX in our engines.

From other sources on the web.

"Nitrogen (N2) is a colorless, odorless and tasteless gas that makes up 78.09% (by volume) of the air we breathe. It is nonflammable and it will not support combustion. It is colorless, odorless and tasteless.
Nitrogen gas is slightly lighter than air and slightly soluble in water. It is commonly thought of and used as an inert gas; but it is not truly inert. It forms nitric oxide and nitrogen dioxide with oxygen, ammonia with hydrogen, and nitrogen sulfide with sulfur. Nitrogen compounds are formed naturally through biological activity. Compounds are also formed at high temperature or at moderate temperature with the aid of catalysts. At high temperatures, nitrogen will combine with active metals, such as lithium, magnesium and titanium to form nitrides. Nitrogen is necessary for various biological processes, and is often uses as a fertilizer, usually in the form of ammonia or ammonia-based compounds. Compounds formed with halogens and certain organic compounds can be explosive."

It would really be a pain have to take my rig to a service center when I want to raise or lower the tire pressure due to changing load requirements.

I do have to put air in my tires ocasionally, it is one of the few services that I still feel qualified to do. Now I should not do that! I wonder if the tire stores pull a vacuum on the tire to evacuate all of the "bad air" prior to filling with nitrogen? Of course I always do that on my AC units as I know that trace moisture causes performace problems. Maybe I will get the tires filled with N2 on one side and see if the other side goes flat first!

Regards,

Jim b

Pop-Pop

An inert gas does not enter into a chemical action with other elements. Argon is an inert gas and for that reason it is used in welding processes where you don't want to contaminate the molten puddle with other non-inert gases. Nitrogen commonly exists in chemical combination with other elements and is in no way inert. Nitrogen doesn't burn, but then neither does air. Nitrogen is used to blanket combustible chemical processes but that is because they want to keep out other gases that may contaminate the process or promote combustion.

The only benefits of using pure nitrogen are:

1. There is no oxidation of the inside of the tire (of course, the outside is not only subject to oxidation, it also gets a healthy dose of ultraviolet light from sunlight, abrasions, wear, etc).
2. The tiny molecules in the air mixture, like hydrogen, are more prone to leaking out than are the bigger molecules of oxygen, carbon dioxide, nitrogen, etc. The average person will not really notice this though since tires do sometimes leak and tire pressures need to be adjusted depending on loading. Any perceived benefit of nitrogen is lost the instant the tire pressure is adjusted by using ordinary free air.

The bottom line that most folks are suggesting is, save your money and just use air.

Now, I want to make the argument that a clean shiny truck really runs better than a nasty one.

TurboTed

Now, I want to make the argument that a clean shiny truck really runs better than a nasty one.


I've noticed that too!(But then, it's only a theory.)

streetsmoker

And just remember that at the time of changing your air, make sure you replace the sparkplugs in your diesel.