Nitrogen filled tires

[edman87k5]

Last time I had tires put on at a shop, they tried to sell me on the nitro fill at $4 per tire. I declined. I have heard of some wanting twice that per tire and more and also being really pushy about it. Similar to charging you $3 for a valve stem that they paid less than $.20 for, they are trying to increase profits.
True, nitrogen particles are larger than air so theoretically it is harder for the tire to lose pressure while setting up and it will not vary in pressure as much while heat cycling on the road.
Atmosphere air is almost 80% nitrogen. I doubt they nitrofill machine puts out 100% pure nitrogen, but lets say it does. You are still only getting 20% more nitrogen in the tire compared to the various gases in atmosphere air. Since the tire has atmosphere air at basically 0 psi when mounted before inflated, unless you purge it (no way to properly do this on any regular wheel), you still have some gas in there that is not nitrogen. So, I feel you are defeating the purpose. I am no scientist, but with a regular air compressor, you are going to have about 80% nitrogen in the tire. WIth noitro fill, that number may get to 95%.
The advertising for it is similar to snake oil claims using scientific data and claims that cannot be proven. Will the tire last longer? Theoretically yes. Proof? None. Will it lose less air while sitting? Theoretically yes. Proof? less than none. They do not bother to tell you that the nitrogen can also escape through the porous rubber. I have had tires that sat for 10+ years on a vehicle and still had 20+ psi in them and they were not nitro fill.
Also, when you check the pressure in your rv tires and find it to be 5 psi low, are you going to haul it to a place that can top it off with nitrogen? Doubt it. You are going to do like 99.99% of other people and put compressed air in it and then defeat the purposed ideal of having nitrogen in it by adding atmosphere air.

I do see the logic of having it in aircraft tires and f1 cars, but in my opinion ( and that of most not selling nitrofill), it is nothing more than a gimmick to separate people from their money.
Why not fill them with argon? Neon? Any other noble gas? Because nitrogen is easier to produce with a cheap machine and profit from.
As for the claims of the oxygen in compressed atmosphere air having a lot of water in it? True- long ago. Any decent shop will have a cooling and moisture removal system on their air supply, so the introduction of moisture into your tire is not like it was 50 years ago when they were rusting wheels apart from the inside.

[edman87k5]

Originally Posted by f1100turbo

I just think theres a lot of claims of no benefit from using nitrogen with out scientific testing to disprove . I would entertain to be proven thats theres not a benefit to using nitrogen
sure its over priced ! my company buys I believe them to be 20 lb cylinders at 20,000 psi for $12.00 a fill .
I think maybe others would feel different if the price was say maybe $1.00 per tire to fill and it was more readily available .
WHY in the world wouldn't you want spot on tire pressures all the time ?
for tire wear and maybe some better fuel economy .
I have been proven wrong before and I have big shoulders .

Most shops that sell it have a purification machine made and sold by NITROFILL, and do not use cylinders. Also, N2 is sold by cubic foot, not weight as far as I am aware. I have nitrogen cylinders in my shop and dont put it in my tires.

[shineysideup]

Originally Posted by edman87k5

Last time I had tires put on at a shop, they tried to sell me on the nitro fill at $4 per tire. I declined. I have heard of some wanting twice that per tire and more and also being really pushy about it. Similar to charging you $3 for a valve stem that they paid less than $.20 for, they are trying to increase profits.
True, nitrogen particles are larger than air so theoretically it is harder for the tire to lose pressure while setting up and it will not vary in pressure as much while heat cycling on the road.
Atmosphere air is almost 80% nitrogen. I doubt they nitrofill machine puts out 100% pure nitrogen, but lets say it does. You are still only getting 20% more nitrogen in the tire compared to the various gases in atmosphere air. Since the tire has atmosphere air at basically 0 psi when mounted before inflated, unless you purge it (no way to properly do this on any regular wheel), you still have some gas in there that is not nitrogen. So, I feel you are defeating the purpose. I am no scientist, but with a regular air compressor, you are going to have about 80% nitrogen in the tire. WIth noitro fill, that number may get to 95%.
The advertising for it is similar to snake oil claims using scientific data and claims that cannot be proven. Will the tire last longer? Theoretically yes. Proof? None. Will it lose less air while sitting? Theoretically yes. Proof? less than none. They do not bother to tell you that the nitrogen can also escape through the porous rubber. I have had tires that sat for 10+ years on a vehicle and still had 20+ psi in them and they were not nitro fill.
Also, when you check the pressure in your rv tires and find it to be 5 psi low, are you going to haul it to a place that can top it off with nitrogen? Doubt it. You are going to do like 99.99% of other people and put compressed air in it and then defeat the purposed ideal of having nitrogen in it by adding atmosphere air.

I do see the logic of having it in aircraft tires and f1 cars, but in my opinion ( and that of most not selling nitrofill), it is nothing more than a gimmick to separate people from their money.
Why not fill them with argon? Neon? Any other noble gas? Because nitrogen is easier to produce with a cheap machine and profit from.
As for the claims of the oxygen in compressed atmosphere air having a lot of water in it? True- long ago. Any decent shop will have a cooling and moisture removal system on their air supply, so the introduction of moisture into your tire is not like it was 50 years ago when they were rusting wheels apart from the inside.

Well said...

[B47]

edman - you bring up a lot of good points and I am not qualified to say they are correct or not. I do most certainly agree with what you say about not hauling a tire that needs 5 pounds of air to a shop that isn't close by simply because they are the only ones that have nitrogen. That's what got me to start this thread after I had my flat and I could not find a shop that had nitrogen - I had to ask myself - is the hassle of servicing my tire with nitrogen worth it?

[TURBS]

Originally Posted by B47

f1100 - not to get into a long term discussion and remember I am leaning towards believing that there is no real benefit to using nitrogen for your tires, I find your statement about keeping your tires serviced to the proper pressure to be what most of the other posters say is the most important thing you can do to keep your tires roadworthy to be right on.

I haven't been to my RV in awhile, but I believe the decal says that cold PSI is 80 - does that sound right for a 33 foot silverback 29rk with 16" wheels?

I have a 30 + foot 5er that 16" load range e tire the Max pressure
On tire is 85lbs the recommended tire pressure listed 3 times
On my camper is 80 psi and that's what I put in them.

My truck has 80psi on the tires but the manufacture recommends 50psi
In the front and 80psi in the rear so that's what I run.

The max listed tire pressure on any given tire is just that. Max
I would go with what manufacture of the camper/motor home/car or truck recommends.

[Dave_Monica]

It's interesting that one of the main claims of nitrogen filling is that the tire won't lose pressure as readily as compressed air. I believe that a vast majority of the time that a tire losses pressure because of damage (punctures) or a poor bead seal on the rim...not permeability through the sidewall. Nitrogen is no cure for that.

Dave

[F and E Damp]

Quote:

One bit of information - In 1987 the FAA issued an Airworthiness Directive (similar to an auto recall, but manadorty by law) that required all Transport Category aircraft ( these are your big Boeings, McDonnell Douglas types) to have their tires serviced with nitrigen instead of air. The reason as stated in the AD is "... to elimate the possibility of a chemical reaction between atmospheric oxygen and volatile gases from the tire inner liner producing a tire explosion."
So the FAA was more concerned with preventing tire explosions and fires( mostly from overheated brakes due to the magnesium wheels)than anything else.

That AD was based on research I and some of my colleagues in the Landing Gear and Brakes group at Boeing were doing. There was a fatal crash of a Swissair Caravelle that started our work. That airplane had magnesium wheels and Mil-H-5606 hydraulic oil. The pilot did a quick dash along the runway to disperse the early-morning mist, then turned around and took off. The overheated brakes cause a tire to explode, igniting the mag wheels and rupturing the hydraulics. The first AD after that made phosphate ester hydraulic fluid (Skydrol) mandatory as it's non-flammable. I think there was also an AD banning magnesium wheels.

Later, a 727 had a tire explosion that blew an 18" hole in the wheel-well pressure bulkhead, also caused by overheating brakes. We caculated that the instantaneous pressure spike inside the tire reached above 10,000 psi. It failed the dual stailess steel cables in the bead of the tire in tension. Most airliners have brake temperature monitoing systems these days. BTW, that incident was non-fatal, thanks to the US Postal Service! Mailbags being carried as cargo jammed in the hole and reduced the rate of decompression in the cabin, and the floor held without collapsing. If that hadn't happened, we'd have had a wreck like the DC10 in France.

As I've said before, if your RV can do 150 mph with a dragging brake and has retractable wheels, use nitrogen. If not, don't waste the money.

BTW, the pressure rating molded into the tire graphics is the maximum allowable. The tire should be inflated according to manufacturers' specs for the weight being carried by the tire.

[MtnGuy]

I have read that N2 tires don't heat up as much as those tires filled with plan ol' air tires (~79% N2). I have also read of advertising that N2 tires give better fuel economy.

So, my tires filled to 50 lbs of 79% N2 go down the road, the air pressure increases to about 56-57 lbs. They are made to do that....that is why the maximum tire inflation figures stat "cold inflation".

So tires filled to 50 lbs. of 95% N2 (about the maximum concentration without excessive purging) heat up less, so let's figure about 52 lbs. of pressure.

Since when does a tire with 52 lbs. pressure get better fuel mileage than a tire with 57 lbs. pressure.

For those that want to use N2 filled tires, do it....there is nothing wrong with that. For those that want to use plain ol' 79% N2 compressed air, do it....there is nothing wrong with that either.

Ain't this a great world....we can make those decisions for ourselves.

[TURBS]

Agreed mtnguy

[B47]

E&E

.

"Later, a 727 had a tire explosion that blew an 18" hole in the wheel-well pressure bulkhead, also caused by overheating brakes. We caculated that the instantaneous pressure spike inside the tire reached above 10,000 psi. It failed the dual stailess steel cables in the bead of the tire in tension. Most airliners have brake temperature monitoing systems these days. BTW, that incident was non-fatal, thanks to the US Postal Service! Mailbags being carried as cargo jammed in the hole and reduced the rate of decompression in the cabin, and the floor held without collapsing. If that hadn't happened, we'd have had a wreck like the DC10 in France."

.
Good to see another airplane guy here -although it is not my intention to turn this into an aviation forum. I didn't see the need to go into as much detail as you did here, although I am sure that some readers here enloyed the background details.

You mentioned the DC10 accident in France - lets not forget about an earlier similar accident that started the whole aft cargodoor/cables issues with the DC10's -that being the accident that occured after takeoff from Detroit. I was working for that carrier and am very familar with the details.

[F and E Damp]

No, I don't want to turn the forum into an aviation one. It's just that there's so much BS about Nitrogen tire inflation, I feel the need to try and debunk the whole thing with specific examples.

[B47]

F&E - IMO it is not so much BS about using nitrogen in your RV tires as it is that other prople have their opinions about it - some from past experience (myself), some from what they have heard about it and some just their personal take about it. That is the reason I started the thread - so as I could get other peoples experiences and opinions and I think we have certainly heard both the pros and cons from them. I think it is safe to say that you don't give much stock to using nitrogen in your RV tires and I am tending to agree with you, but some other posters have their reasons for using it.

This is the second thread I have started here and I can certainly say that I have learned a great deal from other posters from doing so.

This a great forum to hear from other people about things/issues pertinet to the RV life.

[B47]

Well if I had any doubts before about nitrogen filled RV tires before , I don't anymore,

I just checked the pressure of all 4 of my tires with the following results - 3 0f the 4 that came from the factory filled with nitrogen and have not had any servicing at all read between 72 and 75 pounds cold and the 1 that had been repaired after going flat and was serviced with plain air read 55 pounds cold.The recommended decal pressure is 80 pounds cold.

These tires have less than 1100 miles on them - I keep a mileage log. So I am not buying the claim that nitrogen filled tires hold their pressure longer.

I guess I better start looking at portable air compressors!! I really hate to because I have a great big one in my garage, but it sure isn't portable.

[MtnGuy]

Did you consider that the repair might be leaking ??

[B47]

mtnguy - yes I considered that and will keep a record of any future servicing needs for that one tire. If it keeps reading low, then I will have to bring it back in. I have compressed air at the RV storage place and will top all 4 off before leaving mext time.

I guess the main point of that posting is to add to the discussion about nitrogen filled tires and most important is to make myself aware of the need to go buy a portable air compressor. I have looked at Sears and Lowes and will purchase one tomorrow. I am waiting to see what other posters have to say about what ac to buy, but I certainly will have one before I leave on my next trip.

Thanks for your input.

[capndinghy]

Interesting discussion on Nitrogen. My new Rav4 came equipped with nitrogen in the tires but when it time to service them it will be plain compressed air. As far as my RV; it is only getting 6.3 MPG, so I don't think nitrogen filled tires will make any difference.

B47, we have a lot in common. I retired from the same airline a few years ago myself. There is good chance we have flown together.
Regards,
Chuck

[B47]

cap - it is possible we flown together. I was not an Operations Inspector, but rather an Airworthiness Inspector and I am sure you know the difference. But it is possible I performed some Enroute inspections with you.

PM me if you like and we can talk.

[MilCop4523]

once you put air in them to meet max pressure standards you have neutralized teh Nitrogen effect anyway. Why pay more ?

[anitag]

OK - dumb question after reading these posts - our new Flagstaff TT came with NitroFill tires. If needed, can we fill them with plain old compressed air or do we have to use Nitro?

[OldCoot]

Originally Posted by anitag

OK - dumb question after reading these posts - our new Flagstaff TT came with NitroFill tires. If needed, can we fill them with plain old compressed air or do we have to use Nitro?

You can fill them with regular old air from any gas station or home compressor. Reg air is 78% nitrogen, so there is no harm/no runs/no errors & nobody left on base.