Tire Pressures

 There was an article in the "Heloise" newspaper column about over inflating tires.  This is wrong and here is the response I sent in.

Tire Pressure

Tires have two pressures, the maximum safe pressure that the tire will hold, and the pressure that the car manufacturer recommends for the weight and performance of the car it is installed on. The car manufacturers are very conscious of gas mileage and run higher pressures than they did years ago when comfort was the goal.  There might be other recommendations when carrying a heavy load or for towing, so read the owners manual for the correct pressures.

Putting more pressure in can result in decreased braking and handling, along with a rougher ride.  The slight increase in gas mileage will result in faster wear as all of the tire is not in contact with the road. Also, tires heat up after driving for a while, so if set to the maximum pressure, they might be even higher after a trip. 

As a race car driver, we often inflate the tire higher to balance the car and help with the rigors of racing - but our tire life is measured in hours, not miles.

With modern tires it is difficult to tell if they are low just by looking at them.  Every driver should be taught how to use a tire gauge, and tires checked every few weeks before driving.  With many modern cars the tire pressure can be checked through the dash display, but not all cars show the exact pressure of each tire; many will just show if a tire is low.  For every 10 degree drop in temperature, a tire loses about one pound.  So tires especially need to be checked for pressure during Fall and again in the Spring. 

Tires today are very good at holding their pressure.  If your tire loses more than 2 pounds in a week with a stable temperature, consider there may be a nail or similar object in the tire and have it checked out before more damage occurs.