Do you use Nitrogen in your tires?

[dennis thompson]

I was at the car dealer and picked a notice about nitrogen in your tires, it says:
increase tire life by up to 30%
improve fuel economy
reduce chance of tire failure up to 50%
improve braking and handling

it goes on with many other benefits
what do you think, is this correct?
do you use nitrogen in your tire?
thanks

[Stephen Cherry]

I usually just buy tires from tire rack and mount them myself, using air- which is mostly nitrogen.

Nitrogen leaks a little less than oxygen, but, from what I have read, good tires have extra rubber of a certain type that keeps the air in. Cheap tires skimp out on this. The big thing to avoid is the water in the tires- if this is condensing and evaporating with temperature, it will cause larger changes in pressure.

In any case, I just use air, and my tires last OK.

[Jason Roehl]

Nitrogen is used in airliner tires and racing tires. For a typical civilian vehicle, nitrogen has one, and only one, purpose: to separate the civilian from more of their dollars.

[Dave Richards]

As Stephen alluded, what is in your tires now is already 78% nitrogen. I expect you'd be just as well off to find someone who has a dryer on their compressor so you don't get water in your tires when you fill them.

[Eric DeSilva]

Just out of curiosity, anyone know why they don't use CO2? I used to use CO2 cylinders to fill flats on my bike--as a gas, it is nice and compressible. I've also seen some off-road fix-a-flat kind of cans that seemed like pure CO2. Too expensive?

[Curt Harms]

Nitrogen is used in airliner tires and racing tires. For a typical civilian vehicle, nitrogen has one, and only one, purpose: to separate the civilian from more of their dollars.

At least for aviation use, the absence of moisture is the reason for nitrogen, or so I was told. I wonder if it'd also be less corrosive without the 21% oxygen.

[Jason Roehl]

At least for aviation use, the absence of moisture is the reason for nitrogen, or so I was told. I wonder if it'd also be less corrosive without the 21% oxygen.

I believe it's also for the fire-reduction benefits--those tires get very hot, and if there's a fire, then there's not compressed air containing oxygen to contribute. If a nitrogen-filled tire blows on landing due to a fire, it just might put the fire out by starving it of oxygen briefly (kind of like oil well fires are put out with dynamite).

[dennis thompson]

At least for aviation use, the absence of moisture is the reason for nitrogen, or so I was told. I wonder if it'd also be less corrosive without the 21% oxygen.

One of the suggested benefits I didn't mention in my original post was " reduce wheel corrosion", although I have been driving for many years and have never had a problem with wheel corrosion

[mike holden]

I was at the car dealer and picked a notice about nitrogen in your tires, it says:
increase tire life by up to 30%
improve fuel economy
reduce chance of tire failure up to 50%
improve braking and handling

it goes on with many other benefits
what do you think, is this correct?
do you use nitrogen in your tire?
thanks

The answer to this is in the third line: "improve fuel economy". If it did, then the car manufacturers would be specifying nitrogen as the proper inflation gas. They are searching for the slightest increase in fuel economy to meet federal mandates.
They do not specify nitrogen, so at least one of those claims is debunked.

The place where I buy tires, fills them with nitrogen, places a little green ring on the filler cap to remind me. I just top up the tires from my own compressor (air) or if on the road, the local gas station (air).

I would not go out of my way at all for nitrogen.

Mike (M.Sc. in Chemistry; retired from Chrysler)

[Steve Schlumpf]

Dennis, my wife has nitrogen in the tires on her SUV and I have air in the ones on my truck. The nitrogen have held their pressure for over 3 years (35,000 miles) and I have to check and refill my truck tires every couple of weeks! I notice a difference in handling because of the tires... the nitrogen are firmer and do not seem to be subject to weather changes. My truck tires get flat spots from sitting in the garage overnight - especially in the wintertime - her's do not. Next time I get tires... I will get the nitrogen.

[Dan Hintz]

One of the suggested benefits I didn't mention in my original post was " reduce wheel corrosion", although I have been driving for many years and have never had a problem with wheel corrosion

This is the biggest thing (using your brain, not the corrosion thing). For all of the benefits they claim for Nitrogen and all of the horrors they claim for shop air, all one has ot do is look to the past. How many wheels have you ever heard of that corroded because they used shop air? Zero. How do you increase tire life by 30% when the damage to a tire is the reduction in tread thickness due to road wear? You can't. How can you claim to reduce tire failure by 50% when you don't specify what the failure mode you're reducing is? You can't. Not to mention if you could improve failure rates by such a high degree, the NTSB would all but demand it be used.

When I go to the oil change shops, they give me all kinds of useless figures for how each changed component will improve my gas mileage. One day they were going all out, so I added up the percentages in my head... they were essentially promising to improve my gas mileage by 50-60% more than a car right off of the assembly line. Obviously impossible, but they didn't stop to think before speaking.

[Jason Roehl]

One more on the nitrogen thing.

Let's say you fill your tires to 40 psi (I know, high for cars, low for trucks, but the number is a little easier for the following math) with shop air (remember: 78% nitrogen, 21% oxygen, 1% other stuff)

Over the course of a few weeks, your tire drops to 32 psi--because it lost all the oxygen, but not the nitrogen (just using the pro-nitro sales folks logic here). So you top it off with shop air again to 40 psi. Now the pressure over a few weeks drops due to losing oxygen (but not nitrogen!), but to what? well, 32psi is ~80% of 40 psi, then we added 8 psi of 80% nitrogen, so now the nitrogen is about 38.4 psi of the 40 psi. One more cycle and you're up to 39.7 psi due to nitrogen, very little oxygen, and would read 40psi on most gauges commonly available.

Okay, I also have one more: what procedure do these tire shops use to fill tires with nitrogen? Do they simply hook up the nitrogen tank and push in the nitrogen? Because there's still ambient air inside the tire from when it was mounted. They certainly can't pull a vacuum first, as that would collapse the tire, breaking the bead's seal. Do they then deflate the tire and re-fill with nitrogen several times?

Either way, it's snake oil.

Steve, I suspect you just need to have your truck tires re-mounted and bead sealant used. It doesn't take much contamination for a bead to allow a very small leak. I've had truck tires that went years without needing air. As for whether tires get me 30,000 (partial life due to uneven wear) or 40,000 miles (full life due to consistent tire pressure), I don't really care--once the tires are in their last 1/4 of tread life, they're just about worthless in water, snow or mud anyway.

[David Weaver]

Do they charge to put nitrogen in the tires, or are they looking to sell nitrogen as a benefit of getting your tires done there?

I've never had nitrogen in a tire, and I've never had tires that needed air more than once every 6 months unless they've had a nail/wire/screw hidden in them somewhere. Never seen wheel corrosion issues, either. I keep my tires at 40 psi cold.

If the tires are at the same pressure with air and nitrogen, I find the fuel economy claims *very* suspect, and it gets a little irritating to see everyone trying to sell fuel economy with every device, elixir or service that goes on with a vehicle. Those of us who keep after our cars aren't going to find better fuel economy without getting a different car. Those who don't...should learn to keep an eye on the basic things in their cars.

[Matt Meiser]

I noticed Costco, and I think Belle Tire which is one of the major regional players around here use nitrogen at no charge. I've heard some of the others advertising it. Costco appears to have a machine that "makes" nitorogen" which would I suppose would be the exact opposite of a medical oxygen concentrator. Remove the 20% oxygen from the air and you are left with mostly nitrogen.

[Steve Schlumpf]

Jason, my truck is a 97 Chev S-10 and the reason - or so I have been told - that the valve stems leak is because of using aluminum wheels. I replace the stems every couple of years and things work great... until they don't and the process starts all over again.

The dealership we go to does not charge for nitrogen. Course, that could be to get everyone to try it, then charge for the service at some point in the future.