Nitro filled tires.

[roanmountaincampers]

Our trailer has nitro filled tires. When I picked it up the tech that did the PDI stated that they had just been gauged to the correct pressure. When I checked them today I found they had 60 psi instead of the 50 recommended on the sticker. I'm checking with a dail type tire gauge. Do I need a special gauge to check these? If not should I lower them to 50? First time with Nitro filled on any vehicle.

[rockport]

Mine came the same way. When I put my tpms on I realized they were over inflated and reduced them to 50psi cold. I will be curious what others have to say. I did notice on last trip the pressure readings went from 50 psi at beginning of trip to almost 60psi after warming up.

[rattleNsmoke]

As far as I know, no special gauge is necessary. Make sure to check the tires COLD to get an accurate reading. suspect you have 'D' rated tires due to the low(er) pressure. If 50PSI is your max, keep it at that. Relieve pressure if necessary. There has been lots of discussion on nitro filled tires...here on FRF along with various sports car message boards. I think nitro filled tires trickled down from the aviation community where altitude would freeze water molecules in the tires and that's not a good thing for high speed balance. The general consensus is that nitrogen for land based vehicles is good for it's 'dry' component(lack of H2O)in the fill, but totally a sham. Good ol' air from your gas station will be sufficient. Good luck with the new unit!

[OldCoot]

Originally Posted by kb4srn

Our trailer has nitro filled tires. When I picked it up the tech that did the PDI stated that they had just been gauged to the correct pressure. When I checked them today I found they had 60 psi instead of the 50 recommended on the sticker. I'm checking with a dail type tire gauge. Do I need a special gauge to check these? If not should I lower them to 50? First time with Nitro filled on any vehicle.

Just don't hit any holes with nitro in your tires. They will go BANG!

[Oaklevel]

As you know air is about 80% nitrogen just removes the oxygen & misc.... No differences if you want to keep just nitrogen you have to find a tire or car dealer that has the "machine" otherwise just add regular air as needed......... The word is it is supposed to give better gas mileage & have the tires last longer..... Our Subaru had nitro-fill tires.... that set lasted 32K now we just use regular old air & have 45K so far on these tires & the gas mileage is the same........... You use the same tire gauge & treat the tires the same way you normally do..........

[Oakman]

The only advantage I can see to nitrogen filled tires is they don't seem to lose air pressure. Mine have been at 80 psi for over a year now and that includes sitting on the storage lot for 4 1/2 months during the winter.

[roanmountaincampers]

I'll let them down to 50 psi tomorrow. Meanwhile, Old Coot, I'll make sure not to jar them. Thanks for the advice.

[rockport]

Originally Posted by OldCoot

Just don't hit any holes with nitro in your tires. They will go BANG!

That's it. I'm going to bubble wrap my tires now.

[mogman]

Nitrogen in tires is a big dealer upsell. Will cost upwards of $30 to check and fill a camper rig.

[OldCoot]

Originally Posted by rockport

That's it. I'm going to bubble wrap my tires now.

If they have nitrogen in them, save the bubble wrap, but if they're filled with nitro like the OP originally posted, I would just stay away from them or only pull the trailer on VERY smooth roads.

[NCRadioman]

Nitrogen has a lower expansion ratio than air. So as the tires warm up, the pressure does not increase as much as air filled tires will.

As far as your tire pressure goes, if you know your trailer weight, compare it to the tire weight rating marked on the side of the tire. If you approach this "max weight", then use this pressure posted on the sidewall to give you the "max rating" of the tire.

What I find hard to believe is the cost of N2 for this application! I work in a place that pretty much just throws it away, daily, as it is used in our processes.

Continue to have fun!

[Himcules]

unless you had your tires vacuumed all of the air out prior to the nitrogen being filled, then it's useless.

i used to race gt class, open wheel FA and FC cars on nitrogen. properly vacuumed and and then filled with nitrogen. the benefit here is heat control and more consistent pressure between cold and hot.

on street vehicles, it's a gimmick. no where have i seen a vacuum rig to properly deplete the mounted tire of its ambient air and then filled with pure nitrogen. as previously posted, ambient air has about 78-80% nitrogen already. its the balance that has all the moisture that affects pressure once heated.

you do not need a special gauge or tool to measure air pressure with n2 filled tires. but be aware that no two gauge will measure the same unless they are calibrated to each other. i only use my own gauges that i have calibrated once a year. your gauge and the mechanic/tire shops' will be different.

[jadatis]

You should first check the pressure advices given , if they are right , by filling the needed data into my camperRV-tirepressure-calculator.
Then you know wich pressure is save for the tires.

For that I need the GAWR's of your car and from the tires the maximum load and referencepressure( Pr). This Pr is a bit tricky. Its the yyy in "maximum load xxxx lbs AT yyy psi ( cold) and is lower then the maximum pressure of the tire.
In America Loadratings are given in form of letters or ply-rating( C-load/6 ply to H-load/16ply)and then I can get the Pr from that rating.
If you weighed per axle, or better per tire, with load you use the car with, those loads can be used better.

But now about the nitrogen filling. Every ideal gas ( Nitrogen ( N2) and oxigen(O2) are about, and water (H2O) is not) expands the same with rising of the temperature. Water is also expanding the same when it is a gas, but goes over to liquid at a temperature that happen in dayly use. N2 is only done because , by the production of it, it does not contain water, wich can give unpredictable pressurechanches.

Don fuss with trying to get 100% N2 in the tires, in the long while there will be O2 in the tires coming from the outside trough the rubber into the tire, against the high pressure . Has to do with partial pressure witch then is higher for O2 outside the tire then inside . Thought it is called the law of Pascal.

N2 holds more heat energy then O2 , so for short time inside-tire temperature can be lower , but in the long run the inside-tire reaches the same temperature, and the same pressure belonging to that.

[Himcules]

Originally Posted by jadatis

You should first check the pressure advices given , if they are right , by filling the needed data into my camperRV-tirepressure-calculator.
Then you know wich pressure is save for the tires.

For that I need the GAWR's of your car and from the tires the maximum load and referencepressure( Pr). This Pr is a bit tricky. Its the yyy in "maximum load xxxx lbs AT yyy psi ( cold) and is lower then the maximum pressure of the tire.
In America Loadratings are given in form of letters or ply-rating( C-load/6 ply to H-load/16ply)and then I can get the Pr from that rating.
If you weighed per axle, or better per tire, with load you use the car with, those loads can be used better.

But now about the nitrogen filling. Every ideal gas ( Nitrogen ( N2) and oxigen(O2) are about, and water (H2O) is not) expands the same with rising of the temperature. Water is also expanding the same when it is a gas, but goes over to liquid at a temperature that happen in dayly use. N2 is only done because , by the production of it, it does not contain water, wich can give unpredictable pressurechanches.

Don fuss with trying to get 100% N2 in the tires, in the long while there will be O2 in the tires coming from the outside trough the rubber into the tire, against the high pressure . Has to do with partial pressure witch then is higher for O2 outside the tire then inside . Thought it is called the law of Pascal.

N2 holds more heat energy then O2 , so for short time inside-tire temperature can be lower , but in the long run the inside-tire reaches the same temperature, and the same pressure belonging to that.

yes, that is another good point about N2. no one with a street vehicle will routinely cycle the gas in their tires to keep it pure N2 (fully deplete gas by vacuum and then refill with N2). without routine maintenance to ensure the gas is pure N2, O2 will mix in.

again, for street use, N2 is a gimmick and just a waste of money if you are being charged for it.

[F and E Damp]

The only tires that NEED nitrogen are those on jet airplanes. When I was at Boeing, I researched landing gear tire bursts. In the early 1960s there were several accidents that resulted from in-flight bursts of retracted tires, one with 70 fatalities.

The research showed that, if an airplane took off after taxying a long way with a dragging brake, there was a risk of either an over-pressure burst or a tire explosion in the first hour of the flight. We had a 727 case where the tire exploded from gases being released from the rubber compound and then spontaneous combustion. Analysis of the failed tire bead steel cords indicated a pressure of about 12,000 psi!

If your rig can do 150 mph for a couple of miles (with a dragging brake) and then retract the wheels, by all means spend the extra.

[roanmountaincampers]

I agree that nitro in your tires is a waste of money. IT was already in the tire when I bought the unit. I plan to just top them off with my compressor when they need it so eventually I guess I'll just have good old air in there.

[KyDan]

Consumer Reports mag says nitrogen is mostly a gimmick by dealers. They found
no real advantage. As others have said plain old atmosphere is 80% nitrogen
already!
Oh, by the way-- do any of you change the air in your tires when you do
oil changes??

I'M JUST KIDDING!!!

[Lynkage]

Originally Posted by OldCoot

Just don't hit any holes with nitro in your tires. They will go BANG!

You will be able to go faster too!!

[lswartz]

I see a couple posts here that say you don't need a special gauge, maybe they meant for measuring the nitrogen pressure vs. air. You do need a special gauge for each, an accurate one. Most are not, especially at gas stations.

[whj77372]

Am I missing something, my D rated tires run with 65 psi?