OK campers, let's do some math. Oxygen and water vapor are 22% or air. These folks who want to sell you something have a tire, er, tyre at 30 PSI. The oxygen and water vapor leak outs leaving 15 PSI. Too funny.

 

I am a Heavy Jet Tech like a c ouple of the previous people posting on this subject, and they are corret. For normal everyday driving it is not worth the extra trouble.

 

I was just at Discount tire this week, and the sales guy had a newspaper article on the desk. It was about a person that hit a pothole with a tire that was filled nitrogen, and the hole caused the tire to pretty much explode. The only thing that was left of the tire was bits and pieces of tread. The side wall had been totally disintergrated. I don't think I'll be using nitrogen any time soon. Besides, I'm pretty good at keeping my tire pressure up to par.

 

At reasonable temperatures and pressures, nitrogen is relatively inert. I doubt it could cause a blowout.

The only smart thing that has been said about this topic is to keep your tire pressure up to what it should be.

Also, most tires are mounted by pot-hazed, high shool drop outs at your local tire store. They are not concerned with how clean a seal there is between your wheel and the tire or how well the stem is seated. A high end place will charge you more, but they will ensure that the wheel and tire contact area is clean, that the seal is good, and that the wheel and tire are properly balanced on a 3D, road-force machine. I had a wheel on a 300zx that went through four tires in four years because it leaked about 3 PSI every two weeks which caused premature wear. When I switched over to having my race tire guy do my street tires, that same wheel now looses less than 3 PSI every six months. (Yes, it uses just plain old American air as God intended.)

 

The loss of 3lbs or so of air per month is the result of cheap valves. Your tire guy probably put some better valves on the rims. You can get the same results with the cheaper valves by buying some metal caps with rubber seals in the caps. Same results, only have to air up 3 or 4 lbs every 6 months.

 

Let me get this straight?

You race car guys use nitrogen to keep the tire pressure from INCREASING.
Daily drivers should be using nitrogen to keep our tire pressure from DECREASING.

My only explaination is that these tire stores are blowing HOT air and also putting HOT air in our tires...no charge!