257
Car care
Inflation - Tire Pressure
The Tire-Loading Information label shows
the correct inflation pressures for your tires
when they’re cold. “Cold” means your vehi-
cle has been sitting for at least three hours
or driven no more than 1 mile (1.6 km).
Notice: Don’t let anyone tell you that
underinflation or overinflation is all
right. It’s not. If your tires don’t have
enough air (underinflation), you can get
the following:
• Too much flexing
• Too much heat
• Tire overloading
• Bad wear
• Bad handling
• Bad fuel economy
If your tires have too much air (overinfla-
tion), you can get the following:
• Unusual wear
• Bad handling
• Rough ride
• Needless damage from road hazards
Adjust the tire pressure to match the current
load and speed of the car (see page 306).
The stated tire pressures apply to cold tires,
i.e. tires that are the same temperature as
the outside air temperature. Tire pressure
increases as the tires become warm (e.g.
during highway driving) by approximately
4 psi (28 kPa). When the temperature of the
tires changes by 50°F (10°C), the tire pres-
sure will change 2 psi (14 kPa).
Never reduce the pressure of a hot tire. If the
tires are hot when you check them, only
increase the pressure, if necessary.
High speed operation
WARNING
Driving at high speeds, 100 mph
(160 km/h) or higher, puts an additional
strain on tires.
Sustained high-speed driving causes
excessive heat build up and can cause
sudden tire failure. You could have a
crash and you or others could be killed.
Some high-speed rated tires require infla-
tion pressure adjustment for high speed
operation. When speed limits and road
conditions are such that a vehicle can be
driven at high speeds, make sure the tires
are rated for high speed operation, in
excellent condition, and set to the correct
cold tire inflation pressure for the vehicle
load.
93U SM 06.book Page 257 Friday, February 18, 2005 1:15 PM