That's exactly what I was going to check for. Deflate the tire and see if it spits out water like it normally does.
Fortunately I can do this on my truck which by default has nitrogen.

Eliminating water would have a huge benefit for the likes of me.
No way can I put decent amount of miles on any of my cars now, so tires are only replaced every 5 years or longer.
In those five years I have to-top off the tires many times. In process what's happening is that air escaping, but air and water is being put back- or compounding water.

 

That is not what the topic title suggests. There is no 'could' there.

Sorry, can't see the similarity there, at all.

As already commented, not by _that_ much and air _is_ 80% nitrogen anyway.

I agree - seems to me that there is likely do be more difference made by using tyre stations connected to poorly maintained compressors than the air/nitrogen difference. It occurs to me that there may be a likelihood of less moisture and oils from a modern nitrogen compressor than an old air compressor but perhaps not when compared to a new well maintained air compressor.

Yes, and I am providing information for your benefit as in a factual data point and my opinion is as valid as any other here, take or leave that as you please.

 

All you have said is that you saw no difference- snake oil- and you are unanimous in that.
If you want to actually provide data, start by telling us what difference it is that you are talking about, were expecting or promised.

I assumed that you were referring to no difference in fuel consumption, since you mentioned mileage. And certainly one of the promises of nitrogen.
Realize that TPMS itself was invented to get better gas mileage, lower emissions, but if you are good about maintaining inflation, you wont see any difference whatsoever.

 

I think you'll find a significant spike in TPMS issues during El Niño years.

The wife gets irrationally concerned when she sees any tire warning. Here in humid south Tejas we do get some wide temperature swings and I always get a call from her on those occasions that the "computer says something is wrong with the tires!" I'm usually able to talk her down by telling her to get some air at the gas station or drive it home and I'll fill it up from my compressor in the garage. Well, predictably, when the weather cooled off this year, there was a TPMS warning and we were scheduled for our last CPO appointment the next day. I made sure to have the dealer look at the tires and the TPMS. When we came to pick up the car, my wife completely bought in to the service rep's explanation that filling the tires with nitrogen would most likely prevent further low pressure warnings. There were no other problems with the car--even though there was $7,400 worth of "Recommended" repairs. Under pressure from my bride, I skeptically opted for only the $41 nitrogen fill.

A month later I noticed the good old low pressure warning on my way to work. After work, I made a detour to the dealer where I thought I would give them an earful about their nitrogen theory! They apologetically assured me they would check it out and top off all the tires. The technician came back before I had finished my first cookie to say the problem was a screw in the tire. This was surprising since I was the last to drive it and the car had not left the garage in several days--but it turns out my wife had taken a quick trip to the store the night before... The tech said the screw was too near the sidewall to repair. I went back into the bay to have a look and it was a good two inches away from the edge of the sidewall. I said it looked like there was more than enough distance from the sidewall for a repair to made. He sheepishly said they could plug it for $40, but couldn't guarantee it would hold. Since it was getting late, I told them to do it and then went back to the waiting room for another cookie. Forty-five minutes later, with the evening's plans, beyond sitting at the dealership, in jeopardy, I went to find out what the hold up was. The service rep said they would be finished in 15 minutes but when I decided to get a jump on my departure by paying the bill, she said--to my complete astonishment--"Why don't we call it even?" I told her I refused to argue the point with her!

The plug is still holding after three weeks, but I have to side with the snake oil crowd as far as the nitrogen is concerned.

 

$40 to plug a tire!!
Somebody blow the rape whistle.

FYI the plug and the nitrogen is free at Costco

 

Expectations and promises are not data, just anecdotal information and aspirations.

Yes, and no noticeable difference in handling, ride quality or road noise i.e. _no_ difference.

Thank you - I do realise that. I also realise that TPMS stands for Tyre Pressure _Monitoring_ System with the emphasis on monitoring. Nothing gets any better unless you do something about it such as inflate tyre, have screw removed and tyre repaired. I am very careful about my tyre pressures which may be why I see no difference. As with all things, if you _think_ something is an improvement (as in the better octane fuel discussions) it will probably appear to be however I can't help but surmise that many of the magical improvements promised by nitrogen fills are actually a result of the exercise e.g. actually getting the correct pressure in the tyre to within the TPMS limits, a valve seat cleared with dry gas curing a slow leak or perhaps keeping inflation within TPMS limits for seven months instead of six months if you only check your tyres every six and a half months.

 

Believe me when I say I was reaching for the whistle when I ask the service rep how much they would charge for the plug when I could have it done for under $20 at any service station. I reluctantly consented only because it was late, I was already there, and we had important plans for the evening. I think that after trying to carve me for a new tire and taking so long with the repair the rep was a little chagrined and that's why I made it out the door for free. Thanks for the tip about Costco--they're closer to me anyway!

 

Will let you know this time next year if I saw the only difference I am looking for- no change in air pressure as the weather changes from hot to cold.

Supposedly, nitrogen has a much slower leak rate and holds less moisture. Thus tolerant of temp swings.

I can report from 4 years of experience in my climate, when the weather changes there is queue of folks with TPMS warnings.

 

The lack of an ulterior motive at Costco is a game-changer.
Also top pay and thus devoted employees means no pimple faced kid is stripping your lugs.
Believe me it matter if you ever have to change a tire on the side of the road after a kid used the wrong socket and torque.

 

I would ask what the plug procedure was. If it was and internal plug where they remove the tire and plug/patch the tire on the inside then mount and balance it I can see the price. If an external plug then $10-$20 is max.