The practice really came from the trucking industry who feels that nitrogen eliminates oxidation and provides a longer carcass life for re-treads. It's been popularized by some of the racing teams for its ability to lower air loss and being non-flammable. Now a few car amnufacturers are delivering cars with nitrogen-filled tires.
For all intents and purposes - conventional vehicles will gain little from the practice, but if it makes you feel better, then it is better, right?
Always remember the words of Ricardo Montabalm; :It is always better to look good than to feel good."
our dealer is doing it for free for service customers who bought their cars there. My son got it in his Impala today and swears that the car rides much smoother. The service manager said it should help with tread wear and mileage.
I hope everyone realizes that the atmosphere around us (the air) is already composed of 78% Nitrogen. The balance is 21% Oxygen and 1% of a combination of 14 other low level gases. So all of us using air for tire inflation are already heavy Nitrogen users.
I ran it in the tires of one of my crotch rockets for a set of tires and it did seem to hold pressue better and the tires got a bit better life riding in the Arizona heat at speeds. Not sure it would benefit a passenger car unless you did a lot of extended high speed runs. I can't imagine how it would help improve the ride.
Most of those who use nitrogen do it to eliminate water vapor. The pressure difference between a hot tire and a cold one is much less and more predictible with no water vapor. Important for racing... not much for daily driving.
At my buisness,Discount tire co. we provide it free to everyone,the best attribute is its ability to lessen air loss,hence providing constant air pressure,which in turn improves gas mileage,at $3.00 a gallon its a good idea. currently I am getting 17.9 to 19 miles to a gallon on my 2004 xlr, unless of course I put my foot into it.