Nitrogen-inflated tires: Cool!By Aida Sevilla Mendoza
Philippine Daily Inquirer
My car’s tires are cool—not because they shod expensive aftermarket rims, but because they are inflated with pure nitrogen. Filling nitrogen in tires helps to keep the insides of the tires cool, even at high speeds. Thus the valve caps of my tires are green, indicating cool, eco-friendly nitrogen content that enhances fuel efficiency.
I first learned about inflating tires with nitrogen the last time I brought my car to the dealership’s service center for preventive maintenance checkup. Deflating my tires of oxygen and replacing the air with nitro cost P50 per tire, but it was reassuring to know that I am now in the company of race cars, aircraft and emergency vehicles, all of which run on nitro-inflated tires.
The pros of nitrogen-inflated tires outnumber the cons. Nitrogen gas has no water, unlike oxygen which contains water or at least vapor that reacts with the insides of the car tire, with the rubber as well as the metal rim. This can gradually lead to oxidation that causes the formation of rust, adversely affecting the tire’s longevity. Nitro does not react with the tire insides or with the rim, thus prolonging the life of the tire and the rim.
MOLECULES. Since nitrogen molecules are larger than oxygen molecules, nitrogen gas is less likely to leak or escape through the tire valves, thereby maintaining air pressure much better and for a slightly longer period of time. The rubber used for tires and linings in tubeless tires is not impermeable which means air pressure loss can be expected over short or long periods of time. Nitrogen has an extremely lower rate of pressure loss and will reduce the need to frequently add air pressure in tires. Fuel efficiency is indirectly improved since insufficient air pressure in tires increases fuel consumption.
Nitrogen stays cooler so your tires achieve much cooler running temperatures. The cooler temperature could mean the difference between a blow out and just getting a flat. Reduced temperatures mean fewer incidents arising from the excessive expansion of rubber caused by higher levels of heat.
Because of cooler temperatures and less likely deflation, the tire treads will wear out less. A tire that is running low won’t be properly covering the road surface and with lower air pressure, more friction occurs across the surface of the tire. This causes unbalanced wear, which can eventually lead to mild steering problems or the likelihood of developing a leak.
SAFER. Nitrogen is a gas that does not support combustion. In case of an extremely overheated tire catching fire, nitro is safer than regular air which contains oxygen that supports combustion. Running tires at higher temperatures causes pressure to build up inside. When tires reach almost melting-point temperatures, as what happens on the race track or the drag strip, nitro is less likely to increase in temperature compared to oxygen.
That’s why race cars, airplanes and emergency vehicles use nitrogen-inflated tires and also why the average car owner doesn’t need it, says Sam Liuson, managing director of Concept One Wheel Gallery. Liuson points out that nitrogen is not only expensive compared to air, which is free, it is also unavailable at gasoline stations. Only tire dealers and car service centers have it. “Unless you have access to a nitrogen outlet everyday,” he says, “you’ll tend to neglect checking the air pressure in your tires.”
MARGINAL. Liuson added that if nitrogen were that effective, all car companies would recommend it. “Not many people would spend extra to inflate their tires with nitrogen if the benefits are marginal. What’s important is to maintain proper inflation of all your tires, regularly inspect for punctures or cracks and repair punctures immediately to prevent water from entering and causing rust or more damage.”
Most tire problems originate from under-inflation, improper alignment and/or old age, Liuson stressed. If you don’t maintain proper tire pressure, the whole sidewall is collapsing while running. When a soft or underinflated tire hits a pothole, a ply inside is more likely to get torn, eventually resulting in a lump on the sidewall. He advises checking the tire pressure as often as you fill up gas or once every two weeks. Correct improper alignment since it will cause premature and uneven wear. Replace worn-out or bald tires immediately to avoid the risk of hydroplaning, under-steer and dangerously longer braking distances.
OBLONG. Liuson also advises knowing the age of the tire by checking the production date stamped on the outside of the tire before you buy it. Tires that are five to seven years old are less flexible and may become “oblong” or out of round if kept in storage or left on a vehicle that is stored unused for a long period of time.
As for those of you who like to drive fast, Liuson recommends high-performance tires. Factory-installed tires are merely adequate, he says, although with proper inflation and maintenance they may last some 20,000 kilometers.
In the meantime, while my car’s mileage is only a little over 10,000 km, I’ll be cool, figuratively speaking, by inflating my tires with nitrogen.