Light Truck (LT-Metric) Tire:A tire used on light duty trucks
and some multipurpose
passenger vehicles.
Load Index
:An assigned
number ranging from 1 to 279
that corresponds to the load
carrying capacity of a tire.
Maximum In ation Pressure
:The maximum air pressure to
which a cold tire can be in ated.
The maximum air pressure is
molded onto the sidewall.
Maximum Load Rating
:The
load rating for a tire at the
maximum permissible in ation
pressure for that tire.
Maximum Loaded Vehicle
Weight
:The sum of curb
weight, accessory weight,
vehicle capacity weight, and
production options weight.Normal Occupant Weight
:The
number of occupants a vehicle
is designed to seat multiplied by
150 lbs (68 kg). SeeLoading
the Vehicle on page 4-16.
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 in ation pressure as
shown on the tire placard. See
Inflation - Tire Pressure on
page 5-42andLoading
the Vehicle on page 4-16.
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.
Service and Appearance Care 5-41
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. See
When It Is Time for New Tires on
page 5-50.
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 5-52.Vehicle Capacity Weight
:The
number of designated seating
positions multiplied by 150 lbs
(68 kg) plus the rated cargo
load. SeeLoading the Vehicle
on page 4-16.
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 in ation pressure.
See “Tire and Loading
Information Label” under
Loading the Vehicle on
page 4-16.
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
5-42 Service and Appearance Care