anybody has replaced the natrual air in tires with nitrogen in patriot? my friend's esapce came with N2 from factory and haven't lost pressure in about 8 months. I also heard it reduces the weight of the tire, resulting better mile per gallons. Also, if you have added any accessories or part that has added weight you can off set it with reducting the weight of the tires with N2?

Any comments?

I'm sure they had this on an episode of Mythbusters and I think it will reduce the fuel consumption as they are lighter, but I don't think it makes a lot of difference.

My Patriot's tires came from the factory with Nitrogen. The tire pressure has been going down but that is because of the extremely cold temperatures we have been having here.

There is a thread already out there that may add some insight to this topic:

http://www.jeeppatriot.com/forum/showthread.php?t=3827

Spencer

Nitro is the only way to go, F1 teams have been using it for years. Less bleed out (larger atoms) and more stable pressure. All Good!

Nitro is the only way to go, F1 teams have been using it for years. Less bleed out (larger atoms) and more stable pressure. All Good!
Well so far i remember 78 percent of your air is just like that N2. There is no reason to pay extra for a special N2 filling. Itīs a myth.
the reason why F1 teams use it was a different one. Fire resistant? i canīt remember.

We in aviation use N2 in landing gear struts--and air over oil system. The N2 reduceds/eliminates water condensation, and therefore rust which will cause wear and failure of the o-ring seals. I used it in my tires, only because I had a tank and regulator and it was easier and quieter that dragging out the compressor!

Nitrogen in tires reduces the changes in pressure related to temperature because nitrogen has a much more consistent rate of expansion and contraction compared to regular compressed air. That is why you get better milage. The weight change is negligible.

Rends, F1 started using N2 because it is pressure stable though a wide temp range. This gives consistent performance from cold out laps to hot in laps, meaning you go faster more and maybe win. The tech since has trickled down to the common man like traction control and variable valve timing. Regular air is 80%ish N2 but its the 20% that messes up pressures etc. Its always the small percentile that wrecks it for the rest of us :)

The problem with air is the water vapor content. If your compressor has a vapor trap, and you put DRY (very very low humidity) air in your tires it is just as stable as straight N2 or other DRY gas fills.

Helium would be OK too, but it leaks out.

The water vapor is has a large expansion to temperature change ratio.

Also, if the tire is cool enough it will actually have condensation inside the tire which will turn baclk into vapor or steam as the tire heats up.

Rends is right. The air around you is about 75-78% N2, 20-22% O2 and the rest is other inert gases (H2O, CO2, etc.

Water has nothing to do with it either. Water atoms can coexist with N2 atoms so the water theory is all wet. Some racing teams may use it, but then again I've heard of racing teams doing alot of strange things that they swore gave them an edge. Let's also remember that they are dealing with .01 and .001 of a second improvements in lap times or 1/4mile runs.

Everyone would be far better off just making sure their tires were properly inflated. I have noticed lately that the tires are rated for upto 42psi, yet they come from the factory with only 32-35psi. Even dealers still use the 32-35psi rule when they check tire pressure. That 7-10psi could mean an extra 2-3mpg overall.

Other things you can do that will increase performance/mpg....

check your air filter and change it when needed.
change the spark plugs 35-50k miles
check your wheel alignment

Other things you can do to improve fuel efficiency are;

Switch of aircon when it's not necessary
Switch off the heaters if you don't need them on
Switch off the stereo
Switch off the lights

All of these things contribute to what mpg you get.

Everyone would be far better off just making sure their tires were properly inflated. I have noticed lately that the tires are rated for upto 42psi, yet they come from the factory with only 32-35psi. Even dealers still use the 32-35psi rule when they check tire pressure. That 7-10psi could mean an extra 2-3mpg overall.

That extra 7-10 can also decrease your tires life, the sidewall maximum pressure is for a full load on the tire. Over inflation can cause the center of the tire to wear much quicker than the sides.

TPM is one EVIC feature I use alot being in teh desert. Then I can keep my tires relatively high but not worry about them getting too hot with our temp extremes. Only 1 tire place in our area understands that, the rest will set it at 32 in the heat of the afternoon adn then you have 28 in the morning....

Water atoms can coexist with N2 atoms so the water theory is all wet.

Yep. They can. On the other hand an awfully lot of them keep falling and freezing on the roads around here making me feel glad I have a sensible car to drive on them with.

It's a good thing the n2 and most of the other gas molecules don't condense or freeze in normal cold temperatures or I would need a snowmobile instead of something with tires.

I use only the finest pharmaceutical quality halon in my tires.