If the shop puts it in for free I'm good but I'm not paying for nitrogen.

Our air already had 79% in it. The extra 21% isn't that big of a deal on passenger cars. I would be more worried about water or water vapor getting in from a crappy compressor system.

I'm lucky I normally have a SCUBA tank laying around with air in it. So I have very dry air on hand to fill my tires if I need to top them up.

quote:

Originally posted by Yellow Jacket:
Here we go again. Let's talk about the best oil while we're at it.

I'm going to make some popcorn. LOL

Four quarts Marvel Mystery Oil and one quart Anti Seize..

quote:

Originally posted by Krazeehorse:

We use a 78% mix.

Yup. 78% Nitrogen blend works very well.

quote:

Originally posted by V-Tail:

quote:

Originally posted by Krazeehorse:

We use a 78% mix.

Yup. 78% Nitrogen blend works very well.

How do you get it mixed?

quote:

Originally posted by David Lee:

quote:

Originally posted by V-Tail:

quote:

Originally posted by Krazeehorse:

We use a 78% mix.

Yup. 78% Nitrogen blend works very well.

How do you get it mixed?

Normal atmospheric air is ~78% nitrogen, ~21% oxygen, and a little tiny bit of argon, neon, helium, methane, krypton, hydrogen, nitrous oxide, and xenon. Hence the 78% blend is just compressed air.

Passenger car tires not much but a big deal in facing tires. We ran late models back in the early 90s. Used bleeder Valves to keep the pressure consistent. Straight air would expand so much that the bleeders would let so much out that they would be almost flat when the cooled down during a lengthy caution. Nitrogen was a lot more stable. It would still expand and bleed but not as much as an air filled tire.

quote:

Originally posted by smithnsig:
Passenger car tires not much but a big deal in facing tires. We ran late models back in the early 90s. Used bleeder Valves to keep the pressure consistent. Straight air would expand so much that the bleeders would let so much out that they would be almost flat when the cooled down during a lengthy caution. Nitrogen was a lot more stable. It would still expand and bleed but not as much as an air filled tire.

I would guess that was due more to the presence of water vapor, as the gases themselves all behave according to the ideal gas law.

I have nitrogen in my personal truck tires, regular air in my patrol car tires.

Both vehicles have a tire pressure monitor system than detects more than a 10% pressure change.

When I drive my personal truck out of the warm garage into the Colorado winter, the TPMS doesn’t alert.

When I drive the patrol car out it does, usually an hour or so into shift. If I fill the tires in severe cold, below zero, they will be over full by the next morning having sat in the heated garage all night.

Interesting tank. I will at least look at the cost of filling the new tires. If its too big a fee, skibbit.

I had it in my last vehicle. The tires lost the same amount of PSI every month, I didn't notice an advantage of anything with it and got tired of going to the tire store to have it topped off and after 25k miles, I said screw it and just topped them off with air from my compressor.

I find it hard to believe that someone would fall for that scam today and that is what it is.
How about the hand painted pin stripe for $300.

If you buy your tires from Costco, they'll refill them with nitrogen for free for the lifetime of the tire(s).

There's a few theories which make it through the mechanic world

1. Well since military aircraft only use dry nitrogen...
2. Doesn't have moisture, wheels won't rust and tires won't dry rot
3. Molecules won't slip out as easily (yes, heard that one)
4. Won't expand as much as regular air when it gets hot (ie., more consistent tire pressure because you know, NASCAR, drafting, etc)
5. Because that's what they come with from the factory and it preserves your warranty

A primary reason that nitrogen is used in race tires is that the gas/tire pressure does not change with tire temperature fluctuation.

Not worth paying for but nice to have if it is free....

If my tire is low at home, I fill it with my compressor. I don't have a nitrogen tank at home. It would be a PITA to drive to the tire shop if yo u just need air.

Mostly right answers, some not.

For your day to day driver, nitrogen is expensive and doesn't offer a lot of advantage.

Nitrogen is used as the air charge in aircraft in tires, pneumatic struts, and the pressurized side of hydraulic accumulators because it's dry, it's got a more linear relationship with pressure and temperature than an atmospheric mixture, because it doesn't contribute to oxidation and deterioration of wheels, seals and struts (and moisture doesn't condensate out of a pure nitrogen environment), and most importantly, it's inert. It doesn't contribute to tire explosions.

In your family cruiser, neither the tire pressures nor speeds will ever approach a top fuel racer or an aircraft, but aircraft tires are often rated up to 204 knots (about 230 mph), and temperatures can reach much higher values.

In a heavy airplane, simply taxiing a long distance is enough to heat the tires and brakes simply from the tire flex; it heats them up so much that available brake energy is reduced for takeoff and may prohibit a takeoff (used to get it at Amsterdam, during max weight taxiing). The result is a hot tire, and as those tires flex they also contribute to a combustible mixture in the tire atmosphere. With simple compressed air, there's enough oxygen in the air to contribute to combustion and an explosion, especially as tire pressure rapidly climbs with a temperature increase.

By putting nitrogen in the tire, the mixture is made inert. Some aircraft like the C-17 use this feature to reduce the potential for a fuel tank explosion by inerting the atmosphere in the fuel tank using nitrogen injection.

Your car tire isn't nearly so critical, and isn't subject to the same kinds of inflation pressures, tire temperatures, or brake temperatures. The use of nitrogen isn't as critical. If you can get it and use it (cylinders from a welding shop work fine), it won't hurt, but you won't see that much benefit in your family car.

It may help a shop to reduce their duty (liability) in the event of a tire explosion, if the shop can show they put an inert mixture in the tire. That's a benefit to the shop, not much to you, and when you use nitrogen, you'll be paying for it.

Here’s the easy(& cheap) answer to the debate, check tire psi routinely.


Checking psi on a routing basis ‘trumps’ whether you go with regular air or somewhat pure nitrogen.

Never pay extra for nitrogen. Waste of money unless you’re going to race your car.

It's in the tires from Costco, part of the deal, and refilled for free, if it helps wear and life, great.

I've run it on the motorcycle, which doesn't get ridden every day, although thats a goal, and have noticed since the bike has air pressure monitoring, that with the nitrogen the fluctuation in pressure has reduced, and that it loses less PSI over time if it sits for a couple of weeks than when it's got air from the tire compressor only or when we get severe temp drops from like 80 to 50 a couple of days a year

Nitrogen offers no advantage in normally driven road cars. Don't take it unless it is free, don't pay extra for it. The tire/repair shop I work for doesn't even have it. At some point before you got the car, somebody, somewhere may have put nitrogen in the tires (not necessarily the ones currently on it, either), hence the green caps.