Gas filled tires

[hoffbrew]

What is the advantage of filling your tires nitrogen? If and when they get low, can you mix with air?

[hankpage]

Air is about 70% nitrogen so no problem topping off. They claim they run cooler and don't change pressure as much with temp. and less oxidation of rubber. It's about a year now since mine were filled when installed and no loss of pressure YET. I'm not convinced Yet. :rolleyes: There was no extra charge, so what the heck. :cool:

[Jim W]

The other advantaged which most people do not point out is nitrogen is an inert gas. This gas will not expand and over heat thus causing an explosion with your trailer tires do to over pressure.
When I worked for Caterpillar, it was standard practice to fill all earth moving equipment from the factory equipped with rubber tires with nitrogen instead of air. We did this as a safety item on rubber tire equipment to prevent injury and death from air-filled tires. If I remember correctly we started doing this in the mid-70's after several scraper (earth moving equipment) tire failures were attributed to the air over heating and causing the tire to explode and will kill or maim the driver. He sits over the LH tire.
Jim

[CWtheMan]

In the reference provided below you will find lots of very useful tire information. On page #37 of the Truck Tire Service Manual there is a paragraph that expresses Michelin’s take on the use of 100% Nitrogen in their tires.

When Michelin is addressing RV tires they are only referring to self propelled RVs. They do not directly provide tires for the RV trailer market.

http://www.michelintruck.com/michelintruck/toolbox/reference-material.jsp

CW

[Johnnyfry]

I feel that I need to correct 2 errors in JimW’s post regarding Nitrogen in tires.

First, Nitrogen in not an inert gas. It undergoes many chemical reactions and exists in many chemical compounds. The only inert gasses are those in the 8th perios of the Periodic table, they are: Helium, Neon, Argon, Krypton, Xenon and Radon. These gasses undergo no reactions.

Second, ALL gasses (inert and otherwise) obey the Gas law which is: PV=nRT. Basically the law states that with a constant volume of gas (the tire volume), Pressure is directly proportional to Temperature ( in degrees K).

The claimed advantage to using Nitrogen is the fact that Nitrogen molecules are larger than Oxygen molecules and therefore diffuse out through the rubber more easily. Air is 78% Nitrogen, 21% Oxygen and 1% ( mostly inert gasses and Carbon Dioxide). Another possible advantage is reduced oxidation of the tire interior.

Does anyone have any data of using Nitrogen VS Air?

[Johnnyfry]

An addendum to my previous post. Possibly the reduced heating is due to Nitrogen having a different Specific Heat than Air. I need to check that out.

[Johnnyfry]

In another addendum to my earlier post, I meant to say that the Oxygen molecules are smaller and thus diffuse out through the rubber, not the other way round.

Sorry

[Jim W]

I feel that I need to correct 2 errors in JimW’s post regarding Nitrogen in tires.

First, Nitrogen in not an inert gas. It undergoes many chemical reactions and exists in many chemical compounds. The only inert gasses are those in the 8th perios of the Periodic table, they are: Helium, Neon, Argon, Krypton, Xenon and Radon. These gasses undergo no reactions.

Second, ALL gasses (inert and otherwise) obey the Gas law which is: PV=nRT. Basically the law states that with a constant volume of gas (the tire volume), Pressure is directly proportional to Temperature ( in degrees K).

The claimed advantage to using Nitrogen is the fact that Nitrogen molecules are larger than Oxygen molecules and therefore diffuse out through the rubber more easily. Air is 78% Nitrogen, 21% Oxygen and 1% ( mostly inert gasses and Carbon Dioxide). Another possible advantage is reduced oxidation of the tire interior.

Does anyone have any data of using Nitrogen VS Air?

I do not normally correct what other people have post, but when they try to make a point they should check out the entire facts.

I am not a Chemist and have not had chemistry class in over fourty years. An I may have forgotton some of my chemistry schooling since then.

So I went on line and did some more research in my eailer statment about "Nitrogen gas being an inert gas".

Per the Universal Industrial Gases Inc. and I quote" 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." they then go on and state.

"Nitrogen (N2) Applications and Uses:
Multi-Industry Uses for Nitrogen:
The inert properties of nitrogen make it a good blanketing gas in many applications. Nitrogen blanketing is used to protect flammable or explosive solids and liquids from contact with air. Certain chemicals, surfaces of solids, and stored food products have properties that must be protected from degradation by the effects of atmospheric oxygen and moisture. Protection is achieved by keeping these items in (under) a nitrogen atmosphere. "Inerting" or "padding" are other terms used to describe displacement of air and nitrogen blanketing."

This is what the industry states and how we used it in the earthmoving industry, to prevent tire degradation due to oxgen and overheating thus causing an explosine of the tire.
Jim W.

[Johnnyfry]

Good point Jim, I certainly did not mean to insult you. I too would like to know the basis of the Nitrogen claims and it it really works --- and why.

Your experience relating to tires overheating and blowing up was interesting and I was searching for the explanation. Since Nitrogen does obey the gas law the reason must lie elsewhere. I'll keep looking.

On another subject, I see that you have the same 5er and truck as I have (my Ram is an 06) and I saw another post by you concerning this. Do you have an exhaust brake, if so how well does it work? I have not installed one at this point but I am going to go into the mountains next year and am concerned.

Jacobs points out that their unit is factory authorized by Dodge and would not affect any warranty. I called the Dodge dealer and was quoted $1,600- to $1,700 to install. Do you nave any thoughts on this subject?

[Festus2]

Gentlemen:
Hoffbrew's question at the beginning of this thread has been answered thoroughly - with enough scientific information and detail. The "Technical Corner" of this forum is intended for the "technical" aspects of RVing ------ GPS, Satellite TV, stereos and other high tech items - not sure how filling up tires got here but ..........
If you are to get involved in a discussion regarding exhaust brakes, can you move that out this category to a more appropriate one?
Thank you.

[chuck&gail]

Can't say about earthmovers, but airplanes use nitrogen because it does not burn. Race cars use nitrogen because it will not burn AND it is easier to get "dry" nitrogen than dry air. Normal air from an air compressor has lots of water in it. Water expands when heated, and could indeed cause tires to explode. I'll bet earthmovers use it for same reason as race cars. It DOES make a difference at speeds over 100 mph. I do not bother with nitrogen in my RV tires, as I never drive that fast. I just use normal air which is mostly nitrogen anyway.