Thursday, February 4, 2010

Nitrogen in Tires Hoax

I saw a report on Action News last night about using nitrogen to inflate the tires on your car. They made it sound like it was really keen by mentioning the fact that nitrogen is used for race cars and the space shuttle. They also claimed that the tire would retain it's pressure longer with nitrogen than with air.

They also interviewed a manager of a COSTCO tire shop who claimed that based on the studies he had read, nitrogen in the tires makes your car handle better, get better gas mileage and makes your tires last longer.

First of all, it is true that nitrogen is used in race car tires, but it is used to minimize uneven tire expansion due to large, uneven changes in the temperature of the tires. When the tire expands it becomes taller and if the tires do not grow the same, there is a slight change in the weight distribution of the vehicle. This change causes the handling of the race car to change.

One of the reasons pure nitrogen expands less is because it is lacking the moisture that is naturally present in the air. It is also lacking the moisture that is built up inside the tanks of air compressors.

The tires on your street car do not heat up as much as race car tires and they heat up evenly. Also, It does not matter if their is slight weight distribution change on your car because it is designed to handle poorly from the factory. Your car is not designed with an optimum weight distribution and it is designed to understeer for safety.

Unless the tire shop purged the static air out of the tire before filling it with nitrogen, it would not have a pure mixture of nitrogen within it. Also, if you did have a pure mixture, any time you stop to fill it at a air source, you are diluting the nitrogen and you are most likely adding moisture to the tire. You would need to ensure that you only topped off your tires with pure nitrogen to keep any slight benefit you gained from the tire shop. Air is 78% nitrogen.

You can see how much trouble this would be, not to mention expensive if you can't get free nitrogen.

The reason they use nitrogen in the tires on the Space Shuttle is because it does not support combustion.

Proper inflation of your tires promotes good fuel economy and tire life, but the fact that you have nitrogen in your tire has nothing to do with it.

This is just marketing hype, if you get free nitrogen at your tire shop, fine, but don't waste money paying for it.

No comments:

Post a Comment