The NHTSA, the Transportation Department agency responsible for vehicle safety, estimates that monitoring tire pressure could prevent over 10,000 injuries and countless deaths.
The government has proposed a new rule mandating that all vehicles made after November 2003 have systems to warn drivers about low tire pressure. This is in response to the recall of 6.5 million Firestone tires that occurred in August of 2000.
Department of Transportation (DOT) studies have shown that 27 percent of cars and 33 percent of sport utility vehicles and light trucks have at least one under-inflated tire by eight pounds per square inch or more. Under- inflated tires have a greater rolling resistance than properly inflated tires and, therefore, consume more fuel. The DOT estimates that under-inflated tires cause consumers to unnecessarily purchase up to 4 million gallons of gasoline per day. By warning drivers when their tires are under inflated, tire pressure monitors(TPM) will save consumers' money by improving their fuel economy, as well as emitting less CO2 emissions into the atmosphere.
Please visit the website at http://www.nhtsa.gov/
There are something, you should do:
(1) Check tire pressure at least once a month and before going on long trips. Since temperature affects tire pressure, it is best to check tires when they are cold, i.e. have not been driven on for at least three hours.
(2) Fill your tires with the pressure recommended on the tire label, located on the driver's door frame, sill or edge.
(3) If you have any questions about your tires or maintenance, check your owner's manual or consult your dealer.
The following information is from: http://www.safercar.gov/
Q: Why is proper tire inflation important?
A: Proper tire inflation is essential for safe and efficient vehicle operation. Safety experts estimate that 25 percent of passenger vehicles are operated with tires that are under inflated. Vehicles with properly inflated tires experience optimum ride and handling characteristics, shorter braking distances, longer tire life, and improved fuel economy.
Q: Why does tire pressure change?
A: Many factors affect tire pressure including ambient temperature changes and tire damage such as punctures. Tire pressure drops about 1 psi for every 10 degrees F drop in ambient temperature. Additionally, tires lose as much as 1.5 psi per month as air escapes the tire and rim naturally.
Q: Is low tire pressure easily detected by eye?
A: Under inflated tires are visually difficult to detect. It is recommended that tires are inspected and checked monthly with an accurate gauge. The TPMS is not intended to be a substitute for regular tire maintenance. Drivers should consult the owner's manual for information on replacement tires and use of the spare tire.
Q: What are the economic and environmental benefits of proper tire inflation?
A: Vehicles with properly inflated tires consume less fuel, have longer tire life, and emit less carbon dioxide than vehicles with under inflated tires.
Truck Tire Tread Wear Loss Calculation -- Firestone Tire and Rubber Company
10% under inflation = 7% Tread Wear Loss
25% under inflation = 40% Tread Wear Loss
40% under inflation = 65% Tread Wear Loss
Truck Tire Under Inflation Amounts and Results -- The Rubber Manufactures Association & American Society for Testing Materials
3 psi: Tire runs 9% hotter, looses 5% tread life, and costs 1.9% more fuel
5 psi: Tire runs 16% hotter, looses 22% tread life, and costs 3.1% more fuel
10 psi: Tire runs 31% hotter, looses 37% tread life, and costs 6.25% more fuel
Field tests on trucking fleets have shown under-inflation to be as much as 20-30%. This means tires are running 20-30 PSI under-inflated. By advancing the above calculations, this would lead to tires running 40-50% hotter, a loss of tread life of approximately 46-50%, and an increase in fuel consumption of approximately 8-10%.