2010 CHEVROLET IMPALA Owners Manual

TiresYour new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your vehicle Warranty
booklet for details. For additional information refer
to the tire manufacturer.
{
WARNING:
Poorly maintained and improperly used tires
are dangerous.
•
Overloading your vehicle’s tires can
cause overheating as a result of too
much flexing. You could have an air-out
and a serious accident. SeeLoading the
Vehicle on page 5-20.
WARNING: (Continued)
WARNING: (Continued)
•
Underinflated tires pose the same danger
as overloaded tires. The resulting
accident could cause serious injury.
Check all tires frequently to maintain the
recommended pressure. Tire pressure
should be checked when your vehicle’s
tires are cold. SeeInflation - Tire
Pressure on page 6-59.
•
Overinflated tires are more likely to be
cut, punctured, or broken by a sudden
impact — such as when you hit a
pothole. Keep tires at the recommended
pressure.
•
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or if your
vehicle’s tires have been damaged,
replace them.
6-51

Tire Sidewall LabelingUseful information about a tire is molded into its
sidewall. The examples below show a typical
passenger vehicle tire and a compact spare tire
sidewall.(A) Tire Size
:
The tire size is a combination of
letters and numbers used to define a particular
tire’s width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail.
(B) TPC Spec (Tire Performance Criteria
Specification):
Original equipment tires designed
to GM’s specific tire performance criteria have
a TPC specification code molded onto the sidewall.
GM’s TPC specifications meet or exceed all
federal safety guidelines.
(C) DOT (Department of Transportation)
:
The Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.
(D) Tire Identification Number (TIN)
:
The letters
and numbers following DOT (Department of
Transportation) code is the Tire Identification
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides
of the tire, although only one side may have the
date of manufacture. Passenger (P-Metric) Tire Example
6-52

(E) Tire Ply Material
:
The type of cord and
number of plies in the sidewall and under
the tread.
(F) Uniform Tire Quality Grading (UTQG)
:
Tire manufacturers are required to grade
tires based on three performance factors:
treadwear, traction, and temperature resistance.
For more information seeUniform Tire Quality
Grading on page 6-70.
(G) Maximum Cold Inflation Load Limit
:
Maximum load that can be carried and the
maximum pressure needed to support that load.
(A) Temporary Use Only
:
The compact spare
tire or temporary use tire has a tread life of
approximately 3,000 miles (5 000 km) and should
not be driven at speeds over 65 mph (105 km/h).
The compact spare tire is for emergency use when
a regular road tire has lost air and gone flat. If your
vehicle has a compact spare tire, seeCompact
Spare Tire on page 6-86andIf a Tire Goes Flat on
page 6-74. Compact Spare Tire Example
6-53

(B) Tire Ply Material
:
The type of cord and
number of plies in the sidewall and under
the tread.
(C) Tire Identification Number (TIN)
:
The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identification
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire was
manufactured. The TIN is molded onto both sides
of the tire, although only one side may have the
date of manufacture.
(D) Maximum Cold Inflation Load Limit
:
Maximum load that can be carried and the
maximum pressure needed to support that load.(E) Tire Inflation
:
The temporary use tire or
compact spare tire should be inflated to 60 psi
(420 kPa). For more information on tire pressure
and inflation seeInflation - Tire Pressure on
page 6-59.
(F) Tire Size
:
A combination of letters and
numbers define a tire’s width, height, aspect
ratio, construction type, and service description.
The letter T as the first character in the tire
size means the tire is for temporary use only.
(G) TPC Spec (Tire Performance Criteria
Specification):
Original equipment tires designed
to GM’s specific tire performance criteria have
a TPC specification code molded onto the sidewall.
GM’s TPC specifications meet or exceed all
federal safety guidelines.
6-54

Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
(A) Passenger (P-Metric) Tire
:
The United States
version of a metric tire sizing system. The letter P
as the first character in the tire size means a
passenger vehicle tire engineered to standards
set by the U.S. Tire and Rim Association.
(B) Tire Width
:
The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.(C) Aspect Ratio
:
A two-digit number that
indicates the tire height-to-width measurements.
For example, if the tire size aspect ratio is 60, as
shown in item C of the illustration, it would mean
that the tire’s sidewall is 60 percent as high as
it is wide.
(D) Construction Code
:
A letter code is used
to indicate the type of ply construction in the tire.
The letter R means radial ply construction; the
letter D means diagonal or bias ply construction;
and the letter B means belted-bias ply construction.
(E) Rim Diameter
:
Diameter of the wheel in
inches.
(F) Service Description
:
These characters
represent the load index and speed rating of the
tire. The load index represents the load carry
capacity a tire is certified to carry. The speed
rating is the maximum speed a tire is certified to
carry a load.
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Tire Terminology and DefinitionsAir Pressure
:
The amount of air inside the
tire pressing outward on each square inch of the
tire. Air pressure is expressed in pounds per
square inch (psi) or kilopascal (kPa).
Accessory Weight
:
This means the combined
weight of optional accessories. Some examples of
optional accessories are, automatic transmission,
power steering, power brakes, power windows,
power seats, and air conditioning.
Aspect Ratio
:
The relationship of a tire’s height
to its width.
Belt
:
A rubber coated layer of cords that is
located between the plies and the tread. Cords
may be made from steel or other reinforcing
materials.
Bead:
The tire bead contains steel wires wrapped
by steel cords that hold the tire onto the rim.
Bias Ply Tire
:
A pneumatic tire in which the plies
are laid at alternate angles less than 90 degrees
to the centerline of the tread.Cold Tire Pressure
:
The amount of air pressure
in a tire, measured in pounds per square inch
(psi) or kilopascals (kPa) before a tire has built up
heat from driving. SeeInflation - Tire Pressure
on page 6-59.
Curb Weight
:
The weight of a motor vehicle with
standard and optional equipment including the
maximum capacity of fuel, oil, and coolant,
but without passengers and cargo.
DOT Markings:
A code molded into the sidewall
of a tire signifying that the tire is in compliance
with the U.S. Department of Transportation (DOT)
motor vehicle safety standards. The DOT code
includes the Tire Identification Number (TIN),
an alphanumeric designator which can also identify
the tire manufacturer, production plant, brand,
and date of production.
GVWR
:
Gross Vehicle Weight Rating.
SeeLoading the Vehicle on page 5-20.
GAWR FRT
:
Gross Axle Weight Rating for the
front axle. SeeLoading the Vehicle on page 5-20.
6-56

GAWR RR
:
Gross Axle Weight Rating for the rear
axle. SeeLoading the Vehicle on page 5-20.
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 Vehicle on
page 5-20.
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. SeeInflation - Tire
Pressure on page 6-59andLoading the Vehicle
on page 5-20.
6-57

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 6-67.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 6-70.
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 5-20.
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
Vehicle on page 5-20.
6-58