Roger then talked about over inflation and under inflation: RS: If a tire is maintained properly it will wear evenly across what is known as the tread face. When the centre bar is worn down, the tire has been run over inflated. Instead of the contact patch being flat on the ground, the tire is pushed up (it reduces surface area between the tire and the road). You have less stopping traction, less steering traction, and a less stable tire, not to mention that it wears out faster.
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| When the centre bar is worn down, the tire has been run over inflated, and that means you have less stopping traction, less steering traction, and a less stable tire.(Photo: Uniroyal) |
AS: How do we end up with over inflation?
RS: There is too much air in the tire. The issue with that is that a lot of drivers don't understand what the correct air pressure is for their vehicle. They don't know where to find it so they make mistakes.
AS: Where do you find the correct tire pressure?
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| Even more sinister than over inflation, under inflation of even 4 PSI is enough to degrade the quality of the tire and tremendous heat can build up and cause your tire to literally blow out. (Photo: Uniroyal) |
RS: The correct tire pressure is on the tire information sticker. It is usually on the door jam, in the glove box, in the trunk, or on the fuel door, and always in the owner's manual. The myth that we would like to debunk, if you will, is that many drivers think that the correct tire pressure is what is branded on the side of the tire, that's incorrect. That is the maximum air pressure, the do not exceed air pressure for that tire.
AS: What happens when a tire is under inflated?
RS: There is irregular or uneven wear and both shoulders are worn off. Under inflation is more sinister than over inflation. It's more sinister because first of all, most drivers can't tell by just looking at their tires, that they are under inflated. A 4 PSI (pounds per square inch) reduction is enough to degrade the quality of the tire. Tremendous heat can build up, and your tire can literally blow out.