Black plate (18,1)Chevrolet Impala Owner Manual - 2011
3-18 Seats and Restraints
Q: What is wrong with this?
A:The belt is behind the body.
{WARNING
You can be seriously injured by
not wearing the lap-shoulder belt
properly. In a crash, you would
not be restrained by the shoulder
belt. Your body could move too
far forward increasing the chance
of head and neck injury. You
might also slide under the lap
belt. The belt force would then be
applied right on the abdomen.
That could cause serious or fatal
injuries. The shoulder belt should
go over the shoulder and across
the chest. Q: What is wrong with this?
A:
The belt is twisted across
the body.
{WARNING
You can be seriously injured by a
twisted belt. In a crash, you would
not have the full width of the belt
to spread impact forces. If a belt
is twisted, make it straight so it
can work properly, or ask your
dealer to fix it.
Black plate (39,1)Chevrolet Impala Owner Manual - 2011
Vehicle Care 10-39
Tire Sidewall Labeling
Useful information about a tire is
molded into its sidewall. The
examples below show a typical
passenger vehicle tire and a
compact spare tire sidewall.
Passenger (P‐Metric) Tire Example
(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 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.
(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
see Uniform Tire Quality
Grading on page 10‑55.
(G) Maximum Cold Inflation
Load Limit
:Maximum load that
can be carried and the
maximum pressure needed to
support that load.
Black plate (40,1)Chevrolet Impala Owner Manual - 2011
10-40 Vehicle Care
Compact Spare Tire Example
(A) Tire Ply Material:The type
of cord and number of plies in
the sidewall and under the tread.
(B) Temporary Use Only
:The
compact spare tire or temporary
use tire has a tread life of
approximately 5 000 km
(3,000 miles) and should not be
driven at speeds over 105 km/h
(65 mph). 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, see
Compact Spare Tire on
page 10‑68
andIf a Tire Goes
Flat on page 10‑59.
(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
420 kPa (60 psi). For more
information on tire pressure and
inflation see Tire Pressure on
page 10‑44.
(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.
Black plate (41,1)Chevrolet Impala Owner Manual - 2011
Vehicle Care 10-41
Tire Designations
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 carrying capacity a tire is certified to carry. The speed
rating is the maximum speed a
tire is certified to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in psi (pounds per
square inch) or kPa (kilopascal).
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.
Black plate (55,1)Chevrolet Impala Owner Manual - 2011
Vehicle Care 10-55
Non‐TPC Spec rated tires may
give a low‐pressure warning
that is higher or lower than the
proper warning level you would
get with TPC Spec rated tires.
SeeTire Pressure Monitor
System on page 10‑46.
Your vehicle's original
equipment tires are listed on the
Tire and Loading Information
label. See Vehicle Load Limits
on page 9‑12 for more
information about the Tire and
Loading Information label and its
location on your vehicle.
Different Size Tires and
Wheels
If you add wheels or tires that are a
different size than your original
equipment wheels and tires, this
could affect the way your vehicle
performs, including its braking, ride
and handling characteristics,
stability, and resistance to rollover. Additionally, if your vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, and electronic stability
control, the performance of these
systems can be affected.
{WARNING
If you add different sized wheels,
your vehicle may not provide
an acceptable level of
performance and safety if tires
not recommended for those
wheels are selected. You may
increase the chance that you will
crash and suffer serious injury.
Only use GM specific wheel and
tire systems developed for your
vehicle, and have them properly
installed by a GM certified
technician.
See Buying New Tires on
page 10‑53 andAccessories and
Modifications on page 10‑3 for
additional information.
Uniform Tire Quality
Grading
Quality grades can be found
where applicable on the tire
sidewall between tread shoulder
and maximum section width.
For example:
Treadwear 200 Traction AA
Temperature A
The following information
relates to the system developed
by the United States National
Highway Traffic Safety
Administration (NHTSA),
which grades tires
by treadwear, traction,
and temperature performance.
Black plate (57,1)Chevrolet Impala Owner Manual - 2011
Vehicle Care 10-57
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 Safety
Standard No. 109. Grades B and
A represent higher levels of
performance on the laboratory
test wheel than the minimum
required by law. Warning: 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 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 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 if any of these
conditions exist.
Your dealer 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.