Got Nitrogen?

I went to a tire service center to get a routine tire change when this salesman offers me what they called “nitrogen fill.”  He explained to me the process of filling my new tires with nitrogen and the benefits behind it.  He goes on stressing  the keys points-that Nitrogen will help you save on gas and will make your tires last longer.

All he said actually made sense though I was more astonished with how he seemed to have narrated and memorized  the full process , in textbook english at that.

In theory, it’s true.  The  most beneficial characteristic of nitrogen is that it is an “inert” gas, which means it is a property-free, non-reactive substance. Purified nitrogen is more stable and less corrosive than a compressed version of the “normal” air or the air we breathe. Nitrogen has larger molecules, about 400% larger than that of oxygen found in regular air. Hence, while air filled tires typically lose around 2psi every month through normal permeation, nitrogen filled tires will lose no pressure .   Even better, it’s not oxygen, which is the root of oxidation, which eats rubber just like steel, just not as dramatically or visibly.

So why did the studious salesman tell me I was going to save on gas if I filled my tires with nitrogen? Obviously the correctly inflated tires provide less rolling resistance and would therefore lead to greater fuel economy.  Nitrogen keeps tire pressures constant thus in the long run saves gas.

What about the prolonged life of my tires?

The absence of oxygen and other tire degrading contaminants in Nitrogen will help tires last longer. Its non-reactive properties will help keep consistent pressure in the tire thus letting it operate in cooler temperatures, again in theory.

Yes but - in reality, most of us drivers are going to wear out our tires long before the rubber will decay enough to lower tire performance or safety. Whether driven a lot or little, internal tire degradation caused by using normal air won’t be an issue.

The key issue in ensuring longer lasting tires is proper inflation and periodic check-ups. Of course, under-inflated tires reduce gas mileage. They flatten out, creating more surface area and thus adding friction, which makes the engine work harder. The extra friction, and resulting heat, also increases the chance of a blowout. A properly inflated tire is always safer and more efficient than under-inflated one.  Checking your tire pressure once a month does the same thing. This also helps you get close to the rubber for a chance of seeing something else that might be going wrong like irregular wear or cracks and chips. Nitrogen filled tires being a “fill and leave” option makes for a dangerous proposition.

Without a doubt, “nitrogen filling” has its benefits.  Yes  tire pressures will remain more constant, saving you a relatively small amount in fuel and tire-maintenance costs. There will be less moisture inside your tires, meaning less corrosion on your wheels. You won’t  be able to feel any difference in the ride or handling or braking, unless your tire pressures were seriously out of spec and changing to nitrogen brought them back to the proper numbers.  But throw in a few hundreds of pesos  for it and the benefits simply leaks through the rubber.