Posts Tagged ‘Tire Pressure’

This Wednesday Aidan Saves the World

Wednesday, March 9th, 2011

As usual on Wednesday afternoon I am struggling to come up with something simple we can all do to impact the world in a positive way. Aidan had an idea. he told it me it would effect the environment, personal economy, health and safety and world peace. Damn over-achiever.

Here is how he proposes you accomplish all that today. Properly inflate your tires. Yup, that’s it. Properly inflated tires will last longer – saving you money and reducing your drain on the environment. They will increase your fuel efficiency – again saving you a few bucks and saving the environment. And they will respond and handle better – keeping you safer and healthier. And that world peace thing? If we use less fuel we’ll fight fewer battles for oil.

You see, an under-inflated tire can’t maintain its shape and becomes flatter than intended while in contact with the road, the sidewalls bulge a little, internal heat builds up. It’s all bad. Your tires get worn, they don’t handle well, Yup, that’s you, on the side of the road waiting on AAA… or worse in a crash.

The Rubber Association of Canada did a recent study estimating 23% of vehicles in Canada had at least one tire under inflated. Goodyear conducted research aimed at truckers demonstrating that under normal speeds, for prolonged periods a tire 20% under inflated experienced a 16% loss of tire life. That’s a lot!

That same Goodyear study showed a 2.5% reduction in fuel efficiency under the same conditions. Does 20% under-inflated seem like a lot? Its only 6 psi on the average car. And for cars, rather than big trucks, the US Department of Energy says under-inflated tires can lower gas mileage by 0.3 percent for every 1 psi drop in pressure of all four tires. FYI, the proper tire pressure for your vehicle is usually found on a sticker in the driver’s side door jamb and in your owner’s manual. Do not use the maximum pressure printed on the tire’s sidewall.

Tire Rack conducted a Performance Test Track Drive, comparing properly inflated tires to purposely under-inflated tires. They used 2003 BMW 330Ci coupes. The tires installed on one test car were inflated as recommended (29 psi front, 33 psi rear), while the other car had its tires inflated 30% lower (20 psi in the front and 23 psi in the rear). 30% under-inflation is the percentage established by the US DOT at which passive pressure monitoring systems should warn the driver of low inflation pressure .

The under-inflated tires required more steering input to maneuver, steer, corner and were slower to respond. The rear tires’ reactions lagged behind the front tires, resulting in a detached sensation being transmitted to the drivers. It proved to be over 2 seconds slower around our test course (2 seconds represents about a 7% loss of handling performance).
The tires’ ability to move water, i.e. drive in the rain was also seriously compromised.

So that’s it. Go to your favorite neighborhood gas station, check your air pressure, inflate properly, save the world.