The U.S.
Department of Energy estimates that gas mileage can be lowered
by 0.4% for every 1 PSI (pound per square inch) drop in the pressure of
all four tires.
The Rubber Manufacturers Association states that 85 percent of drivers
surveyed do not check their tire pressure properly, and many don't even
know where to find the recommended proper tire inflation for their
vehicle.
*Calculations based on US Department of Energy gas consumption estimates
and assumption that underinflation value persists unchanged throughout
the year.
