We’ve hashed this out here before, but I thought it was interesting the today’s (at least it was today’s here) newspaper column drew the same conclusion. These columns are also posted elsewhere on the Car Talk website. That’s where the link came from.
Same here. And lots more folks read the column than drop by here, so I’m happy it’s getting wide exposure.
Racers use N2 because 1) it is dry air, no water vapor and 2) because they carry N2 tanks to air up the tires and run their air tools. N2 is cheap at the gas supply. That doesn’t mean everyone needs to use nitrogen. Just a well maintained compressor with a water separator. If you are really OCD about moisture in the tire, use a small dryer ball like painters use on the hose end right before the tire fill valve.
I’ve never seen dry rot on the inside of a tire; ever. Granted, the column gets more exposure and will deter some but the nitrogen campaign is so widespread and pushed so hard I don’t think it will go away anytime soon.
Carfax is pretty much a load of cxxp also and in spite of forums and even a segment on 20/20 about them they march on.
The CarMD ads seemed to have slacked off some though… 
Pneumatic tools can use compressed air just as well as nitrogen. There must be another reason racers use nitrogen instead of air. Maybe it is a safety issue, and compressed air might fan the fire if it starts, while nitrogen would tend to suppress it.
Racecars use nitrogen in their tires because, it’s more stable/predictable than the prevailing atmosphere. When you’re dialing in a racecar for the very best performance a difference of 2psi can be the difference between winning and coming in 5th. When calculating how much tire pressure will raise during a race, it’s easier to make a judgment with nitrogen where the engineers know exactly how it’s going to respond to the higher tire temps when a car is at speed than it is to do with air.
For an ordinary car on the road, there’s very little benefit though. My take on it is that if it’s free, go ahead, Costco includes a nitrogen fill when you buy tires from them. But if an outfit is charging for the service, then decline it.
I just checked out the comments at the end of the newspaper column. I especially liked the one about the “bottom air” being the problem with tires.
Yeah “centripetal force” ? So much for that comment.
I guess my idea of tires having two valve stems ( one for regular air and one for nitrogen ) is not worth pursuing.
I wouldn’t dismiss the idea of 2 valve stems. People have made money over far less innovative ideas.
Besides, it would make for a better balanced wheel assembly…
A thought on racing and tires.
A nitrogen tank is a whole lot easier and safer to store and transport than an air compressor and the engine and fuel to run it.
Regardless, nitrogen sounds so much more exotic. You can’t beat the brag factor.
Ding ding ding, +1 to @CapriRacer on why racers use nitrogen. And nitrogen doesn’t make any noise when in use, a gas compressor does.
Another tid-bit, you can jack the line pressure waaaaay up with an N2 regulator and run your impact wrenches waaaay faster. If you are ever in a NASCAR pit box, check the regulator pressure, it is not 90 psi! Club racers don’t really need that, but its fun anyway.
Marketeers saw it in the racer’s pits, put it in tire stores and it is NOT coming out!