I'm gunna fill mine with Helium 
Hmm, won't even need the snorkel if I can get it to float
Hmm, won't even need the snorkel if I can get it to float
Gas Mileage (Improved with Nitrogen filled tires??)
- Thread starter Pioneer
- Start date
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Nobody gets 21mpg consistently. IMHO, no mileage is worth reporting unless you get it consistently (i.e. a trend over time, many tanks). Anything less is just an unusual or specific set of circumstances that you wouldn't expect to encounter in routine driving, not to mention the likelihood of some error in either miles traveled or gallons consumed - especially in one-off situations.
Another reason nitrogen is used is because the pressure in them doesn't change as much as air when the temperature changes. However, as long as you keep your tire pressure set correctly, there should be no mileage difference. Tires filled with 40 PSI of air = tires with 40PSI of nitrogen as far as mileage is concerned.
We have a tyre sales company here in OZ, that likes to promote nitrogen in tyres. You tend to see a lot of women driving cars with red valve caps here, as well as guys that are easily talked into sales gimmicks.
One motoring organisation here has made it public that putting nitrogen in your tyres is a waste of time. It's no good putting the stuff in 4WD tyres if you're regularly changing tyre pressures.
Also, I often see comments about 'We don't buy these vehicles for their economy'. When I bought my two landcruisers I made sure that I bought diesels because they were more fuel efficient (off road, open road towing, and around town) than petrol versions. I use higher tyre pressures on open road trips for better economy, and I avoid using the a/c unless I get too uncomfortable. What I'm trying to say is that economy is always on my mind and just because these vehicles aren't as economical as a modern day Peugeot Turbo diesel (or whatever) doesn't mean that you completely disregard fuel usage.
I'm happy to say that my 12H-T powered 60 series cruiser gets better fuel economy than my 6 cylinder petrol powered ford falcon (very popular family and commercial car here). My 80 series 1HZ diesel (5 speed manual) got over 20 mpg (imperial gallons) with our around town daily driving dropping/picking up kids from school. Unfortunately this economy dropped after fitting the aftermarket turbo.
One motoring organisation here has made it public that putting nitrogen in your tyres is a waste of time. It's no good putting the stuff in 4WD tyres if you're regularly changing tyre pressures.
Also, I often see comments about 'We don't buy these vehicles for their economy'. When I bought my two landcruisers I made sure that I bought diesels because they were more fuel efficient (off road, open road towing, and around town) than petrol versions. I use higher tyre pressures on open road trips for better economy, and I avoid using the a/c unless I get too uncomfortable. What I'm trying to say is that economy is always on my mind and just because these vehicles aren't as economical as a modern day Peugeot Turbo diesel (or whatever) doesn't mean that you completely disregard fuel usage.
I'm happy to say that my 12H-T powered 60 series cruiser gets better fuel economy than my 6 cylinder petrol powered ford falcon (very popular family and commercial car here). My 80 series 1HZ diesel (5 speed manual) got over 20 mpg (imperial gallons) with our around town daily driving dropping/picking up kids from school. Unfortunately this economy dropped after fitting the aftermarket turbo.
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alia176
SILVER Star
Pioneer,
That's awesome mileage. Just for giggles, I'd be curious to see what your mileage would be if you went back to Flagstaff!! In any case, you may have a very efficient vehicle. Maybe it's the FRAM filter that we all love so much
That's awesome mileage. Just for giggles, I'd be curious to see what your mileage would be if you went back to Flagstaff!! In any case, you may have a very efficient vehicle. Maybe it's the FRAM filter that we all love so much
I'm curious what Pioneers short term and long term fuel trims are. Also, if his timing is at stock.......Just thinking out loud.
This reminds me of another way to purify the N2...
On an episode of Trucks, Stacy David was talking up the benefits of nitrogen in tires. He was saying that the smaller O2 molecules slip past the bead more easily.
So, according to him, if you just continue to fill your tires with regular compressed air, the O2 will seep out, leaving the N2 behind.
Jonald
I cant remember the number of gallons used, or the miles driven but I was there see the 20mpg
I was real happy my sweetheart got 13.8
very proud.
I was real happy my sweetheart got 13.8
very proud.
Nitrogen allows you to run at the full rated Psi of a given tire without the risk of overinflation due to heat.
Nitrogen is used in most race tires to keep the tires uniform.
Nitrogen is used in Indy cars because they measure the diameter of the tire to determine wear.
Road and track has also reported about the molecules not slipping past.
Nitrogen is used in most race tires to keep the tires uniform.
Nitrogen is used in Indy cars because they measure the diameter of the tire to determine wear.
Road and track has also reported about the molecules not slipping past.
I got 8.8 - 9mpg on 90%freeway, 6 miles to work & back over the last two months. I just installed my Dan o rama 02's & had my injectors cleaned. I'll report the change when I fill up in 2 weeks. (I'll be eccstatic with 15)
Cruiserdrew
On the way there
Phil-I'm sorry but this just isn't right. The amount of thermal expansion with nitrogen vs air (which is 80 % nitrogen) at these temps and pressures is the same. I think it's Boyle's Law that would say the expansion would be the same, since they are acting as ideal gasses at these temps and pressures.
The best argument for nitrogen, and the only one that has any bearing to passenger car tires, is the absence of water. I can buy that. The rest of it is hype. If you are operating at the margin, on the outer edge of the envelope, maybe this trace amount of water becomes important. I'll keep that in mind the next time I take my 80 series to 200 mph.
CO2 is something different. It must be more soluble in rubber, because even though it is a bigger molecule, it leaks out faster.
Andrew I will be the 1st to admit I know nothing about Boyle's law or any other. I speak from experience of using compressed air out of a compressor vs Nitrogen.
On long trips in a loaded Cruiser using compressed air with no filter I would find psi to rise after several hours on the road and an increase in altitude. It was not the case when using nitrogen. It was explained to me that it was the moisture in the compressors air that caused the increase.
Ideal gas or not. At highway speeds the tires pressure will increase. Reducing the rolling resistance of the tire (smaller contact patch). Even if N2 was able to stay more stable at the temps observed there is no basis for a tire to roll "better" at a lower psi.
I heard a 150 mile estimate. How much fuel did you go through??
I once got 20 mpg out of my old FJ40 with the stock 2F. It was between Tonopah and Hawthorne. There was about 6 to 12" of snow on the ground and I was in and out of 4wd.. That was once..
I heard a 150 mile estimate. How much fuel did you go through??
I once got 20 mpg out of my old FJ40 with the stock 2F. It was between Tonopah and Hawthorne. There was about 6 to 12" of snow on the ground and I was in and out of 4wd.. That was once..
Nitrogen changes pressure with heat more uniformly. It is not an issue of the nitrogen, so much as it is an issue of the water vapor that is not present in nitrogen. The problem with the water in air isn't that it is going to rust stuff, it's that at some temperatures (below the dew point), it will be a liquid, whereas at warmer temperatures it will be a gas and increase the pressure much more than the increase in pressure due the to heating of the gases alone.
This is a big reason why aircraft use it. You put air in your tires, which is warm and above the dew point, take off, fly up to where the dew point is below the temperature (where clouds are forming) and air in your tires will start to have the water vapor condense. It might freeze, it might just lower the pressure in your tires a bunch, but regardless it's not something that the FAA is willing to allow commercial planes to risk.
Race cars have similar concerns. You fill air in one tire one day at such and such humidity and then fill air up another tire on another day with different humidity, and as the tires warm up, the temperatures will change at different rates. Having tires off by a couple PSI can probably be an issue at 200mph.
Does any of this matter for a Landcruiser doing 70 mph with 285 mud-terrains? Nope.
This is a big reason why aircraft use it. You put air in your tires, which is warm and above the dew point, take off, fly up to where the dew point is below the temperature (where clouds are forming) and air in your tires will start to have the water vapor condense. It might freeze, it might just lower the pressure in your tires a bunch, but regardless it's not something that the FAA is willing to allow commercial planes to risk.
Race cars have similar concerns. You fill air in one tire one day at such and such humidity and then fill air up another tire on another day with different humidity, and as the tires warm up, the temperatures will change at different rates. Having tires off by a couple PSI can probably be an issue at 200mph.
Does any of this matter for a Landcruiser doing 70 mph with 285 mud-terrains? Nope.
Grench
SILVER Star
There is some half-truth to the compressed air & water thing. It certainly doesn't apply to the air coming out of the air chuck in the tire shop.
If you have liquid water turning into gas in the tire, I could see a rapid expansion. If you are using a compressor going directly into the tire, maybe, if you do it over many many cycles you might get enough water to make a difference.
Now, if you are bringing the air to 100psi in a compressor with a tank, the majority of the water in the air will fall out in the tank as condensate. This is the water you drain out of the tank at the end of the day. The air that you release from the tank into your tire is then drier than the air in the atmosphere that it started from.
Chemistry & Chemical Engineering were a long long time ago for me. However, IIRC, water in air is always at a balance of three states, solid liquid and gas. It is the proportion of the three that changes as relation to temperature and pressure. If the pressure increases while the temperature stays the same, the amount of moisture that the air can hold lowers. The other way to think about this would be like a pressure cooker. The higher the pressure, the higher the boiling point of the water in the cooker.
So, as the pressure in the tank is higher than atmospheric (considerably so) the ability of the air in the tank to hold water vapor decreases and the water falls out in the tank. Conversely, when the pressure is released as it enters the tire, it cools.
PV=nRT
Pressure * Volume = number of moles * Constant R * Temperature
As the pressure decreases the volume increases and/or the temperature decreases. This is why when you point the compressed air at something and blast it, condensate can form. The air you're blasting is likely drier than the air in the room, it is just colder.
The water that drains out of the compressor is the proof.
Now we get to the half truths. At the tire store or any other professional shop for that matter, the compressors will be large AND they will have a drier on the air supply. They do this to protect their investment in impact wrenches.
The air the tire store puts in your tire is some of the driest you'll find.
The air coming out of your household air compressor with a tank and without a drier is likely dry enough. It is especially dry if the air outside is cold.
If you connect an air compressor directly to the tire and pump it up, you are likely putting some water into it. How much depends on the humidity when & where you do this.
Like I said, Chemistry was a number of years ago. If anyone wants to slap me down on the above, step right up. The above is as I recall and may not be wholly accurate.
YMMV
If you have liquid water turning into gas in the tire, I could see a rapid expansion. If you are using a compressor going directly into the tire, maybe, if you do it over many many cycles you might get enough water to make a difference.
Now, if you are bringing the air to 100psi in a compressor with a tank, the majority of the water in the air will fall out in the tank as condensate. This is the water you drain out of the tank at the end of the day. The air that you release from the tank into your tire is then drier than the air in the atmosphere that it started from.
Chemistry & Chemical Engineering were a long long time ago for me. However, IIRC, water in air is always at a balance of three states, solid liquid and gas. It is the proportion of the three that changes as relation to temperature and pressure. If the pressure increases while the temperature stays the same, the amount of moisture that the air can hold lowers. The other way to think about this would be like a pressure cooker. The higher the pressure, the higher the boiling point of the water in the cooker.
So, as the pressure in the tank is higher than atmospheric (considerably so) the ability of the air in the tank to hold water vapor decreases and the water falls out in the tank. Conversely, when the pressure is released as it enters the tire, it cools.
PV=nRT
Pressure * Volume = number of moles * Constant R * Temperature
As the pressure decreases the volume increases and/or the temperature decreases. This is why when you point the compressed air at something and blast it, condensate can form. The air you're blasting is likely drier than the air in the room, it is just colder.
The water that drains out of the compressor is the proof.
Now we get to the half truths. At the tire store or any other professional shop for that matter, the compressors will be large AND they will have a drier on the air supply. They do this to protect their investment in impact wrenches.
The air the tire store puts in your tire is some of the driest you'll find.
The air coming out of your household air compressor with a tank and without a drier is likely dry enough. It is especially dry if the air outside is cold.
If you connect an air compressor directly to the tire and pump it up, you are likely putting some water into it. How much depends on the humidity when & where you do this.
Like I said, Chemistry was a number of years ago. If anyone wants to slap me down on the above, step right up. The above is as I recall and may not be wholly accurate.
YMMV
I gotta tell you guys you seem to missing a critical aspect to all this N2 stuff. Its not a matter of chemistry, and it does not matter whether it helps mileage or not, it does however help costco sell tires.
A large proportion of folks dont even know what N2 is, and when you try to explain it to them they get all glazed over and just start buying into what they are being told. Ask a costco fella what about the ideal gas law and see what kinda response you get. I bet hes thinking i eat beans i get gas its ideal.
N2 does contract and expand less than plain old air, but for the rigs we drive and the conditions we drive under can the observed advantage be sufficiently large enough to overcome all the other parasitic drag forces in a cruiser and yield better fuel mileage? I for one doubt that it does.
Karl
A large proportion of folks dont even know what N2 is, and when you try to explain it to them they get all glazed over and just start buying into what they are being told. Ask a costco fella what about the ideal gas law and see what kinda response you get. I bet hes thinking i eat beans i get gas its ideal.
N2 does contract and expand less than plain old air, but for the rigs we drive and the conditions we drive under can the observed advantage be sufficiently large enough to overcome all the other parasitic drag forces in a cruiser and yield better fuel mileage? I for one doubt that it does.
Karl
I personally love the added gas mileage I get from having nitrogen filled tires. Its almost as good as the savings I get from putting acetone in my fuel tank 
I've studiously avoided this thread, but it's late and I'm waiting for the Ambien to kick in.
No way is an 80 Series going to get 20mpg at 75-80 as the speed is given. I have put 160,000 miles on my 1FZ and log stuff as it's my business to be anal. Even when the truck was new, broken in, well broken in, and now properly broken in it just cannot do it. I once got 18 on a rural highway descending gently into a valley with a tailwind and still remember it. Was a 100 mile stretch or something with synthetic oil, synthetic gear oil in the diffs, stock tires at 10psi over and no load.
Somewhere I have a curve showing the HP at each speed for an 80. I've forgotten what the power output was, but do recall the curve got steep around 65 and was heading skyward by 80. Tires are going to make a contribution, but at those speeds it's all about aerodynamic efficiency and the 80 body designers said "meh" to it, instead warmly embracing a big, functional beast that would do whatever you asked of it. You decide your burn rate with your right foot. At 60, that big Straight 6 will ease along and get you 17-18 mpg.
What I do like about its economy is what I'll call its "working economy". Most SUV mpg drops into the single digits when towing a big trailer. Ours gets a pretty consistent 12-13mpg pulling a 3 ton boat at 60-65 and I get the idea they spent a little time playing with final drive ratios, rich cylinder operation, etc so these gals would be reasonable for working types to use. My friends get horrible mpg towing their boats on the same trip - single digits - and their boats are smaller. So I can live with it - especially since I just filled up for $1.99/g here at Chevron!! Whoo hooo! The global warming myth has been discovered - go out and celebrate....
DougM
No way is an 80 Series going to get 20mpg at 75-80 as the speed is given. I have put 160,000 miles on my 1FZ and log stuff as it's my business to be anal. Even when the truck was new, broken in, well broken in, and now properly broken in it just cannot do it. I once got 18 on a rural highway descending gently into a valley with a tailwind and still remember it. Was a 100 mile stretch or something with synthetic oil, synthetic gear oil in the diffs, stock tires at 10psi over and no load.
Somewhere I have a curve showing the HP at each speed for an 80. I've forgotten what the power output was, but do recall the curve got steep around 65 and was heading skyward by 80. Tires are going to make a contribution, but at those speeds it's all about aerodynamic efficiency and the 80 body designers said "meh" to it, instead warmly embracing a big, functional beast that would do whatever you asked of it. You decide your burn rate with your right foot. At 60, that big Straight 6 will ease along and get you 17-18 mpg.
What I do like about its economy is what I'll call its "working economy". Most SUV mpg drops into the single digits when towing a big trailer. Ours gets a pretty consistent 12-13mpg pulling a 3 ton boat at 60-65 and I get the idea they spent a little time playing with final drive ratios, rich cylinder operation, etc so these gals would be reasonable for working types to use. My friends get horrible mpg towing their boats on the same trip - single digits - and their boats are smaller. So I can live with it - especially since I just filled up for $1.99/g here at Chevron!! Whoo hooo! The global warming myth has been discovered - go out and celebrate....
DougM
Nitrogen? Better fuel mileage because of?
I'm with you oh wise OLD one.
Now what do I get for agreeing with the Shaman.....................
agomez
Frijoles
I personally love the added gas mileage I get from having nitrogen filled tires. Its almost as good as the savings I get from putting acetone in my fuel tank
if we install the tornado/vortec thingy you should see an additional increase in mileage as well......
