Tire Inflation Pressure and Performance

You probably already know that a tire's air pressure can have significant affects on its performance. This article will discuss some of the performance factors that are affected by air pressure.

First, it can be very difficult to tell if a tire is under-inflated or over-inflated by simply looking at it. The only way to truly assess the tire's air pressure is to correctly measure it with a proper quality tire gauge. Always check your tires' air pressures at least once a month, and prior to taking any highway trips. If necessary, adjust your air pressures according to the vehicle's owners manual or as indicated on the vehicle tire placard in the door frame.

Second, the tire's load capacity is determined by tire size and inflation pressure. Smaller tires have lower load capacities than larger tires, just as tires with low air pressure have lower load capacities than tires with high air pressure. Again, make sure your tires are inflated to the proper inflation pressure for the load you're carrying. Also, be sure not to overload your vehicle and exceed the load rating of your tires.

Third, when a tire is under-inflated or over-inflated, the tire can (and probably will) wear unevenly. Proper air pressure in the tire will provide an even distribution of load across the tread pattern and will optimize the stability of the tire's structure. Under-inflated tires will tend to wear faster on the outside edges of the tread pattern, whereas over-inflated tires will tend to wear faster down the middle of the tread pattern. Under-inflated tires will also experience higher rolling resistance and decreased durability.

Finally, under-inflated tires will provide less stability for the vehicle. This is because the tire will flex more when cornering and stopping due to it having less air pressure than needed. Under-inflated tires will not respond as quickly as they would when properly inflated, thus negating the performance that was originally designed by the tire manufacturer.