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). See Vehicle
Load Limits on page 8-12.
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. See Tire
Pressure on page 9-49 and
Vehicle Load Limits on
page 8-12.
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.
See When It Is Time for New
Tires on page 9-56.
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. See Uniform Tire Quality
Grading on page 9-58.
9-48 Vehicle Care
Vehicle Capacity Weight:The
number of designated seating
positions multiplied by 150 lbs
(68 kg) plus the rated cargo load.
See Vehicle Load Limits on
page 8-12.
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” under Vehicle
Load Limits on page 8-12 .
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 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
Vehicle
Load Limits on page 8-12 .
How you load your vehicle
affects vehicle handling and
ride comfort. Never load your
vehicle with more weight than
it was designed to carry.
Vehicle Care 9-49
Wheel Alignment and
Tire Balance
The tires and wheels on the vehicle
were aligned and balanced carefully
at the factory to give the longest tire
life and best overall performance.
Adjustments to wheel alignment and
tire balancing will not be necessary
on a regular basis. However, if there
is unusual tire wear or the vehicle
pulls to one side or the other, the
alignment should be checked. If the
vehicle vibrates when driving on a
smooth road, the tires and wheels
might need to be rebalanced.
See your dealer/retailer for proper
diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts
should be replaced. If the wheel
leaks air, replace it (except some
aluminum wheels, which can
sometimes be repaired). See your
dealer/retailer if any of these
conditions exist.
Your dealer/retailer will know the
kind of wheel you need.
Each new wheel should have
the same load-carrying capacity,
diameter, width, offset and be
mounted the same way as the
one it replaces.
If you need to replace any of the
wheels, wheel bolts or wheel nuts,
replace them only with new GM
original equipment parts. This way,
you will be sure to have the right
wheel, wheel bolts and wheel nuts
for the vehicle.{CAUTION
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts on your vehicle can be
dangerous. It could affect the
braking and handling of your
vehicle, make your tires lose
air and make you lose control.
You could have a collision in
which you or others could be
injured. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
Notice: The wrong wheel can
also cause problems with bearing
life, brake cooling, speedometer
or odometer calibration, headlamp
aim, bumper height, vehicle
ground clearance, and tire or tire
chain clearance to the body and
chassis.
See If a Tire Goes Flat on page 9-62
for more information.
9-60 Vehicle Care
