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Nitrogen & TPM

2.7K views 12 replies 10 participants last post by  Santa Fe  
#1 ·
#2 ·
IMHO there is no drawback to Nitrogen - other than cost. Some of the prices I've seen advertised are ridiculous. There are no compatibility issues with TPMS or adjustments required. Air is something like 70% Nitrogen anyway - so the advantage is not huge, esp on the street.
 
#3 ·
Thank you Jeff for your comment. I am not sure about the prices here in KSA I'll check it out soon. Of course, some users claim that
1. they can drive up to 100,000 mile on the tires (that doesn't interest me).
2. the tire never explodes.
3. tire doesn't lose air.
4. stability in extreme hot weather; i.e. the weather here in Saudi Arabia.

My only interest in Nitrogen filled tires is safety then convenience since our CS come without spare tires.

My only concerns are:
1. If TPM is compatible with Nitrogen.
2. If there is something bad about such idea that I don't know.

Thank you again.
 
#4 ·
There would be no problems with the TPMS. Regular checking of the tire pressures with a really good gauge is a good habit to get into and should give you all the benefits of adding a bit more nitrogen to the inside of the tire without the expense (and it allows you to have a weekly inspection look at the wheels and tires).
 
#5 ·
This has been widely documented. Nitrogen gives negligible differences in the tyre's characteristics. Some claim the tyres warm faster, though personally I think this is hearsay and assumed on the physics of gasses rather than specific testing in a lab.

Theoretically Nitrogen tyres lose gas slower. When I ran Nitrogen in my Subaru's wheels for a 18 months I did notice that they didn't drop over the 3-month period as much as they used to, but that may simply mean I didn't ride any pavements at the time.

There is absolutely no reason why TPMS will not work with any innert gas.

All in all, theoretically, Nitrogen is better. How much? Less than you'd give a damn. For me, the inability to partially top-up one wheel with air is much more significant than the minuscule benefits. Say one wheel has a slow leak, do you fill part of it up with air? And if you do, how hot are the rest of your tyres when you do it? Recommended pressure is cold, do you know if they all heated up the same? I'm much more concerned with having a 3psi actual difference left-to-right than I am concerned that Air isn't Good Enough for my wheels. I gave up on nitrogen when the shop next to my house was selling four wheels-worth for 8 Euros.
 
#6 ·
Nitrogen is widely used on commercial and business aircraft. Doesn't create moisture in the tire during filling, and doesn't expand has the tire heats during landing.(air expend when heated up nitrogen doesn't).
Car tires are not submitted to the high difference of temperature an aircraft tire is put through -50F at altitude and the extreme heat of landing. The difference tire pressure due to the extreme, if filled with air could cause a blow out on landing. How good nitrogen in your car tire? For sure you will have no tire pressure difference due to temperature changes(help tire wear). As far as how much, if you drive a lowered cayman like me, not much. I would say no more then few hundred miles on a rear set.
 
#7 ·
...Doesn't create moisture in the tire during filling, and doesn't expand has the tire heats during landing.(air expend when heated up nitrogen doesn't)...
Didn't take freshmen chemistry in college (or in high school for that matter)?? ALL gases expand when heated, and when held in a container of stable volume (such as a sealed tire), must increase pressure if they can't expand.

I punctured a tire at only 2K mi on my new Croc. They filled it with standard air. Other 3 tires are nitrogen-filled. I notice the nitrogen tires tend to be slightly more stable as far as pressure when running hot, but only 1 or 2 psi max. Not worth the expense of finding a service center with nitrogen.
 
#9 ·
I agree w/ the non-chemists assessment..

1) Porsche (and other manufactures) expect and designed for tire pressure to increase whle driving... why else would the TPMS show increases in pressure when driving?

2) When I first learned about "nitrogen filled tires", and people actually paying money for it I fell about the place laughing...

Air is 80% Nitrogen, 18-19% Oxygen and 1-2% other gases.

I figured "now they've figured out a way to sell AIR"...:hilarious:

(Just like the "pre-diluted" antifreeze... for a 50/50 mix you pay 75% of the cost of a 100% container of antifreeze... great gimmick (yeah, yeah... I know it should be distilled water)

I could picture taking my car to the local tire store... "please check the pressures"... "OK, Mr T"... "what is that compressor sound I hear?"... "oh, we're topping your tires off w/ "NITROGEN"... :hilarious: "How much?"... "bend over"
 
#10 ·
Here's what I said about nitrogen in another thread:

Nitrogen will expand when hot, just like any other gas. The reason people say things like "nitrogen keeps the pressure constant" is not because of any special properties of nitrogen, it's because bottled nitrogen is drier than outside air.

Outside air contains water vapor at whatever the relative humidity is for that day. A given amount of water vapor occupies far more volume than the same amount of water in liquid form. If you have water vapor (from the air) in your tires, and a small amount of it condenses into liquid, the pressure will go down more than just if the air cooled off. Likewise, when the tire heats up, the liquid water vaporizes, the pressure will go up more than it would if the air just heated up.

It doesn't take much moisture in the air to make a big difference. I'm not talking about puddles in your tires, I'm just talking about some water vapor condensing into some tiny little micro droplets of water. The condensation or vaporization of a small amount of water causes big pressure changes.

As bottled nitrogen contains far less moisture than outside air, this effect is minimized.

On the other hand, unless you are in Formula 1 and you need absolute precise control over your tire pressure, outside air, with a small amount of moisture, is just fine.

From this thread:
http://www.planet-9.com/cayman-boxs.../cayman-boxster-tires-wheels/31335-goodyear-f1-eagle-assymetric-impression.html
 
#11 ·
I had nitrogen added when I bought new rears for my CS. The most significant benefit for me is that the TPMS completely stopped with inane warnings, resets, etc. It's been almost 3 months/3k miles in hot coastal GA weather and I've not had to add anything to the tires, the TPMS has not gone off once! If for no other reason other than the stability it adds, I'd highly recommend it to all. The additional cost is worth the piece of mind.