Occupant Distribution:Designated seating positions.
Outward Facing Sidewall:The side of an
asymmetrical tire that has a particular side that faces
outward when mounted on a vehicle. The side of the tire
that contains a whitewall, bears white lettering, or
bears manufacturer, brand, and/or model name molding
that is higher or deeper than the same moldings on
the other sidewall of the tire.
Passenger (P-Metric) Tire:A tire used on passenger
cars and some light duty trucks and multipurpose
vehicles.
Recommended In ation Pressure:Vehicle
manufacturer’s recommended tire inflation pressure as
shown on the tire placard. SeeInflation - Tire Pressure on
page 5-51andLoading Your Vehicle on page 4-27.
Radial Ply Tire:A pneumatic tire in which the ply cords
that extend to the beads are laid at 90 degrees to the
centerline of the tread.
Rim:A metal support for a tire and upon which the tire
beads are seated.
Sidewall:The portion of a tire between the tread and
the bead.
Speed Rating:An alphanumeric code assigned to a
tire indicating the maximum speed at which a tire
can operate.Traction:The friction between the tire and the road
surface. The amount of grip provided.
Tread:The portion of a tire that comes into contact
with the road.
Treadwear Indicators:Narrow bands, sometimes
called wear bars, that show across the tread of a tire
when only 1/16 inch (1.6 mm) of tread remains.
SeeWhen It Is Time for New Tires on page 5-53.
UTQGS (Uniform Tire Quality Grading Standards):
A tire information system that provides consumers
with ratings for a tire’s traction, temperature, and
treadwear. Ratings are determined by tire manufacturers
using government testing procedures. The ratings are
molded into the sidewall of the tire. SeeUniform
Tire Quality Grading on page 5-55.
Vehicle Capacity Weight:The number of designated
seating positions multiplied by 150 lbs (68 kg) plus
the rated cargo load. SeeLoading Your Vehicle
on page 4-27.
Vehicle Maximum Load on the Tire:Load on an
individual tire due to curb weight, accessory weight,
occupant weight, and cargo weight.
Vehicle Placard:A label permanently attached to a
vehicle showing the vehicle’s capacity weight and
the original equipment tire size and recommended
inflation pressure. See “Tire and Loading Information
Label” underLoading Your Vehicle on page 4-27.
5-50
In ation - Tire Pressure
Tires need the correct amount of air pressure to operate
effectively.
Notice:Do not let anyone tell you that
under-in ation or over-in ation is all right. It is not.
If your tires do not have enough air (under-in ation),
you can get the following:
Too much exing
Too much heat
Tire overloading
Premature or irregular wear
Poor handling
Reduced fuel economy
If your tires have too much air (over-in ation), you
can get the following:
Unusual wear
Poor handling
Rough ride
Needless damage from road hazards
A Tire and Loading Information label is attached to the
vehicle’s center pillar (B-pillar), below the driver’s
door latch. This label shows your vehicle’s original
equipment tires and the correct inflation pressures for
your tires when they are cold.The recommended cold tire inflation pressure, shown on
the label, is the minimum amount of air pressure
needed to support your vehicle’s maximum load carrying
capacity.
For additional information regarding how much weight
your vehicle can carry, and an example of the tire
and loading information label, seeLoading Your Vehicle
on page 4-27. How you load your vehicle affects
vehicle handling and ride comfort, never load your
vehicle with more weight than it was designed to carry.
When to Check
Check your tires once a month or more. Do not forget to
check the compact spare tire, it should be at 60 psi
(420 kPa). For additional information regarding
the compact spare tire, seeCompact Spare Tire on
page 5-66.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You cannot tell if your tires are properly inflated
simply by looking at them. Radial tires may look properly
inflated even when they are under-inflated. Check the
tire’s inflation pressure when the tires are cold. Cold
means your vehicle has been sitting for at least
three hours or driven no more than 1 mile (1.6 km).
5-51
