oakland_mike

you guys are funny.

I drag race morotcycles and I use only nitrogen to fill the tires. This is done in virtually all motorsports professional racing. The reason that is done in racing is because the the nitrogen does not expand when heated like atmosphreic air. This will keep the tire from 'growing' and changing the ratio of your drive train from engine to the ground.

I don't know how this fits in with daily driver cars or where the savings can come from. It seems to me that the engineers would have already taken this into account when calculating the drivetrain ratios and what is the desired result for the vehicle.

Just bought a Scion XB two days ago and I am luvin' it!

Tomas

There are a number of reasons for use of nitrogen as the fill for aircraft tires, but the most important are pressure stability, lack of moisture, and less oxidation. http://www.physlink.com/Education/AskExperts/ae192.cfm

The reason SOME of us might be looking askance at this whole topic is it has come up every few months for years, and the very same information gets batted about, and everyone leaves with the same opinion they came in with. (My personal opinion is 'yes, it probably is an advantage, but an insignificant one for me.')

Try looking at what turns up in a search... Here's one:
https://www.scionlife.com/forums/vie...nitrogen+tires
and another:
https://www.scionlife.com/forums/vie...nitrogen+tires
and another:
https://www.scionlife.com/forums/vie...nitrogen+tires
etc.

(Yes, I'm suggesting a search before starting yet another topic on any subject. That way new discussion benefits from all the discussion that has gone before, and it concentrates the discussion into one topic instead of spread all over the site in dribs and drabs. It also makes it a lot easier for folks to find the ONE concentration of data on any particular subject, instead of having to look at 20 to find the ONE they want.)

Tomas

HeathenBrewing

:: insert blushing icon here ::

Ok…after some more research, I have to say that if I could fill my tires with N for a quarter or two, I would do it. Probably not going to get any significant increase in MPG and the extended tire life is also debatable since most tires lose the tread or blow out (due to under inflation or damage) before they rot from O2 and moisture exposure.

To be honest, I never heard of inflating w/ N until maybe a week ago, when I saw the advert banner hanging from my dealer. I never researched it until I came across this thread. I was excited to find a way to increase MPG, regardless of how small. Thats why I switched to synthetic oil….not because of the possible horsepower gain, but I will use 50% less oil (6K/6month OCI) plus get a slight increase in MPG (a percentage or 2) for just a little bit more cost than dino oil.

I should have known I was on the wrong path by the initial reply from Tomas.

I did my research and now I know.

I still stand by decreasing oil/fuel consumption, even if only by fractions. But N filled tires are not the way to do it.

1anonymous1

OH f***! For $40, you'd better fill'em with nitrous! as least that way you can enjoy the money you're wasting! A friend of mine once said... "it's time to pull over and change the air in your tires'.

Tomas

If a large increase in MPG was as simple and cheap as ANY of the "Increase MPG!!!" products, there would be at least ONE manufacturer, getting fined yearly for not meeting their CAFE requirements, who would do it to at least SOME of their vehicles...

It's not that none of them work, it's just that most of 'em create some other odd problem, OR don't make enough reliable difference to be worth the cost and hassle.

(Off topic... Wayyyyyy back in the dark ages, when I was a tech at a TV station, we used to have large tanks of anhydrous nitrogen sitting around to pressurize the coax feed to the antenna - to keep moisture out - you don't want moisture in a long run of 4" rigid coax hauling nearly half a million watts).

Even in the phone company, we used to sometimes dry out wet cables by forcing dry nitrogen through them. It sometimes even worked.

And of course in the USAF we kept the aircraft tire guts dry with it.)

Tomas

NC_Pinz

Exactly.

And anyone who believes that nitrogen doesn't expand when heated is a bonehead. Nitrogen as with any other compressed gas will expand when heated. A basic chemistry book will tell you how much based on the temperature increase.

Its just another money making scheme. N2 won't hurt but does nothing to help a passenger car.

Tomas

A little OT, but...

Hey! We think we have neat, odd vehicles - the guy just above me here has a 6X6 Pinzgauer. :D

That's one of the few vehicles I would concede to with my old Land Cruisers. One tough little unit!!!

Tomas

NC_Pinz

Still OT...yep that would be it. Its the third Pinz I've had in addition to a Unimog. It goes with the whole slab-siding xB theme.

OneBadBox

Here's a link to an engineereing forum. Lots of very knowledgable folks over there.
http://www.eng-tips.com/viewthread.cfm?qid=120996

My user name is JDana over there. I posted a link in the above linked thread to another nitrogen thread on TheCarLounge. i also mentioned whom I trust for getting the real technical information.

Nitrogen? Bah!

GrantR

When people talk about saving weight when using Nitrogen... well, I just about laughed out loud Tossing some math at the problem gives you this:

Approximate weight of the air in four 185/60r15 tires (xA factory spec) at about 30psi is: 17.3 ounces. For nitrogen: 16.8 ounces. Weight savings? 17.3 - 16.8 = half an ounce. Woohoo!

The only dubious gain to using nitrogen as others here have said is that it may help the tires keep air pressure for longer. But relying on nitrogen to maintain air pressure is pretty stupid - tires leak air to varying degrees anyway. You always want to keep an eye on air pressure no matter what you're using to fill them. At which point if you're checking your air pressures regularly you don't have any need to use nitrogen in the first place.

Fuel mileage gains occur simply because the tires were just filled to the correct (or higher) pressure from a probably lower pressure because people weren't keeping the air pressures right.

Davestoaster

As an aircraft mechanic, the reasons Tomas sites for using nitrogen in aircraft tires is correct. The number 1 reason is pressure stability at different temperatures. This is the benefit for automobile tires.

A heavy jet tire goes from a sub zero temperature and 0 mph, from crusing at 32,000 feet for a few hours, to a few hundred degrees temperature and almost 200 mph in less than a second, on landing. This would cause a major pressure rise if that tire was filled with just air. So much so, that the tire would most likely explode. Filled with nitrogen, the tire pessure rises only about 10% to 15%. Sometimes a little more on hot summer days.

The benefit for our cars is that when the temperature changes from summer to winter, the pressure in your tires stays almost the same. Lots of people cruise around on low tires here in the northeast because they forget to fill thier tires when the weather turns cold. And just the opposite when the weather turns warm in the summer.

Also on a long trip or high speed with air in your tires, your tire pressure rises. Sometimes a lot. So, if they are already over inflated.........BOOM !!! Not so with nitrogen.

As a note, COSTCO fills all their new tires up with nitrogen free when you are a member there.

brambling

What % nitrogen do these tire stations claim? Ingersoll-Rand doesn't claim any that I could find.

Oh wait I found it. 95% with unknown margin of error.

http://www.alltiresupply.com/prochur...ill_rates.html

Air is 78%, so you're paying for 17% more N2! In maybe 100g of air. It's got to be insignficant.

TRDBox

^^^^^^ very correct

the reason it has become so big is because of the pressure monitoring system that alot of new cars have

imagine if our cars had that and you test drove your car and everything is fine and then you close the deal and drive your box home and on the way your light comes on that says low pressure
a bit upsetting considering its a new car

this is happening way too much and is 1 of the many reasons its getting bigger

also i didnt see it pointed out that oxygen is reactive at high temps and will eat away at the inside of tires and aluminum

all that money we spend on wheels and tires 30-40 bucks isnt going to kill me

that .75 cent you spend to check your tires is most likely putting oil and water from that hose in your tires adding to the problem

nitrogen is dry and clean

TRDBox

most do 95%

TRDBox

most of the membranes gives out 99.9% nitrogen but the machines dont use a vacumm so they will not get all of the oxygen out
usually they will deflate and inflate the tires twice and it will read about 95-97% n2

brambling

You're more likely to lose pressure to a faulty valve or a hole in the tire. If you check your tires weekly, I can't see how 17% more N2 would make a difference.

That thing about oxygen in the air eating away at the tires and alloy wheels is just baloney. There are other factors like potholes or road salt more likely to harm your wheels. Your tires are gonna wear away from use before oxygen or UV would any noticeable affect.

scionetics

And if by chance your nitrogen filled tires need to be topped
off after some time. What a pain to be restricted to taking your
car to only a few places that have nitrogen.

EVILDAVE

Oh ya by the way if anyone needs any I have a quart of AAA blinker fluid for sale!

13edge

^^^
Which has to rank up there with the Flowbee for the dumbest creations of all time. I'm ____ed a light comes on for maintenance. I'd beat the car with a bat if a light kept coming on for tire pressure because it changed from a hot day to a cool night. It's almost as dumb as those talking cars from the 80's... - "Your door is ajar." Well golly gee... good thing you can talk or who knows what would have happened!

For airplanes? Great idea... because we use nitrogen in plane tires. For cars, where air is the most common? Terrible idea, because pressure will change and you don't need a light coming on to scare the crap out of you, as long as you check pressure bi-weekly.

brambling

I was thinking unless you mount your tires in a pure nitrogen environment, the majority of air in the tire will always be atmospheric or 78% N2. You can't suck all the air out through the valve stem, then fill it all back with pure nitrogen. You're at most going to displace at most, what, 50% of the air? With a 17% higher concentration of N2? It doesn't seem you could increase the % of N2 by more than a few degrees this way.