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Intended Outboard Sidewall:The side of an
asymmetrical tire, that must always face outward
when mounted on a vehicle.
Kilopascal (kPa):The metric unit for air
pressure.
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 Inflation Pressure:The maximum air
pressure to which a cold tire can be inflated. The
maximum air pressure is molded onto the
sidewall.
Maximum Load Rating:The load rating for a tire
at the maximum permissible inflation 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 Vehicleon
page 6!32.
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 Inflation Pressure:Vehicle
manufacturer's recommended tire inflation
pressure as shown on the tire placard. See
Inflation - Tire Pressureon page 7!65andLoading
the Vehicleon page 6!32.
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.
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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 Tireson
page 7!73.
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 Gradingon page 7!76.
Vehicle Capacity Weight:The number of
designated seating positions multiplied by 150 lbs
(68 kg) plus the rated cargo load. SeeLoading the
Vehicleon page 6!32.
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 the
Vehicleon page 6!32.
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Inflation - Tire Pressure
If your vehicle is a Two-mode Hybrid, see the
Two-mode Hybrid manual for more information.
Tires need the correct amount of air pressure to
operate effectively.
Notice:Do not let anyone tell you that
under!inflation or over!inflation is all right.
It is not. If your tires do not have enough air
(under!inflation), you can get the following:
.Too much flexing
.Too much heat
.Tire overloading
.Premature or irregular wear
.Poor handling
.Reduced fuel economy
If your tires have too much air (over!inflation),
you can get the following:
.Unusual wear
.Poor handling
.Rough ride
.Needless damage from road hazards
A vehicle specific Tire and Loading Information
label is attached to your vehicle. 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, see
Loading the Vehicleon page 6!32. 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 pressure of the spare
tire. SeeSpare Tireon page 7!98for additional
information.
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Temperature–A, B, C
The temperature grades are A (the highest),
B, and C, representing the tire's resistance to the
generation of heat and its ability to dissipate heat
when tested under controlled conditions on a
specified indoor laboratory test wheel. Sustained
high temperature can cause the material of the
tire to degenerate and reduce tire life, and
excessive temperature can lead to sudden tire
failure. The grade C corresponds to a level of
performance which all passenger car tires must
meet under the Federal Motor Vehicle Safety
Standard No. 109. Grades B and A represent
higher levels of performance on the laboratory test
wheel than the minimum required by law. It should
be noted that the temperature grade for this tire is
established for a tire that is properly inflated and
not overloaded. Excessive speed, underinflation,
or excessive loading, either separately or in
combination, can cause heat buildup and possible
tire failure.
Wheel Alignment and Tire Balance
The tires and wheels on your vehicle were aligned andbalanced carefully at the factory to give you the longesttire life and best overall performance. Adjustments towheel alignment and tire balancing will not benecessary on a regular basis. However, if you noticeunusual tire wear or your vehicle pulling to one side orthe other, the alignment might need to be checked.If you notice your vehicle vibrating when driving on asmooth road, the tires and wheels might need to berebalanced. See your dealer/retailer for properdiagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked, or badlyrusted or corroded. If wheel nuts keep coming loose,the wheel, wheel bolts, and wheel nuts should bereplaced. If the wheel leaks air, replace it (except somealuminum wheels, which can sometimes be repaired).See your dealer/retailer if any of these conditions exist.
Your dealer/retailer will know the kind of wheelyou need.
Each new wheel should have the same load-carryingcapacity, diameter, width, offset, and be mounted thesame way as the one it replaces.
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