width GMC ACADIA 2009 Owner's Manual

Page 26 of 420

Q:What is wrong with this?
A:The belt is behind the body.
{CAUTION
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.
{CAUTION
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/retailer to x it.
1-22 Seats and Restraint System

Page 312 of 420

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.
(A) Tire Size
:The tire size
is a combination of letters and
numbers used to dene aparticular 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
Specication)
:Original
equipment tires designed to
GM’s specic tire performance
criteria have a TPC specication
code molded onto the sidewall.
GM’s TPC specications 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 Identication Number
(TIN)
:The letters and numbers
following DOT (Department
of Transportation) code is the
Tire Identication 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
seeUniform Tire Quality Grading
on page 5-51. Passenger (P-Metric) Tire
Example
5-36 Service and Appearance Care

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(G) Maximum Cold Ination
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 aregular road tire has lost air and
gone at. If your vehicle has a
compact spare tire, seeCompact
Spare Tire on page 5-81andIf a
Tire Goes Flat on page 5-55.
(B) Tire Ply Material
:The type
of cord and number of plies in the
sidewall and under the tread.
(C) Tire Identication Number
(TIN)
:The letters and numbers
following the DOT (Department
of Transportation) code is the
Tire Identication 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 Ination
Load Limit
:Maximum load
that can be carried and
the maximum pressure needed
to support that load.(E) Tire Ination
:The
temporary use tire or compact
spare tire should be inated
to 60 psi (420 kPa). For
more information on tire
pressure and ination see
Inflation - Tire Pressure on
page 5-41.
(F) Tire Size
:A combination
of letters and numbers dene a
tire’s width, height, aspect ratio,
construction type, and service
description. The letter T as the
rst character in the tire size
means the tire is for temporary
use only.
(G) TPC Spec (Tire
Performance Criteria
Specication)
:Original
equipment tires designed to
GM’s specic tire performance
criteria have a TPC specication
code molded onto the sidewall.
GM’s TPC specications
meet or exceed all federal
safety guidelines. Compact Spare Tire Example
Service and Appearance Care 5-37

Page 314 of 420

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 rst 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
range and speed rating of the
tire. The load index represents
the load carry capacity a tire is
certied to carry. The load index
can range from 1 to 279. The
speed rating is the maximum
speed a tire is certied to carry
a load. Speed ratings range
fromAtoZ.
Tire Terminology and
Denitions
Air 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.
5-38 Service and Appearance Care

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Additionally, if your vehicle has
electronic systems such as anti-lock
brakes, rollover airbags, traction
control, and electronic stability
control, the performance of these
systems can be affected.
{CAUTION
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
specic wheel and tire systems
developed for your vehicle, and
have them properly installed by
a GM certied technician.
SeeBuying New Tires on page 5-49
andAccessories and Modifications
on page 5-3for 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. This
applies only to vehicles sold in
the United States. The grades
are molded on the sidewalls of
most passenger car tires. The
Uniform Tire Quality Grading
(UTQG) system does not apply
to deep tread, winter-type snow
tires, space-saver, or temporary
use spare tires, tires with nominalrim diameters of 10 to 12 inches
(25 to 30 cm), or to some
limited-production tires.
While the tires available on
General Motors passenger cars
and light trucks may vary with
respect to these grades, they
must also conform to federal
safety requirements and
additional General Motors Tire
Performance Criteria (TPC)
standards.
Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on
a specied government test
course. For example, a tire
graded 150 would wear one
and a half (1.5) times as well
on the government course as a
tire graded 100. The relative
performance of tires depends
upon the actual conditions of
their use, however, and may
depart signicantly from the
Service and Appearance Care 5-51

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Wheel Alignment and
Tire Balance
The tires and wheels on your vehicle
were aligned and balanced carefully
at the factory to give you 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 you
notice unusual tire wear or your
vehicle pulling to one side or the
other, the alignment might need to be
checked. If you notice your vehicle
vibrating 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 your
wheels, wheel bolts, wheel nuts,
or Tire Pressure Monitor System
(TPMS) sensors, replace them only
with new GM original equipment
parts. This way, you will be sure to
have the right wheel, wheel bolts,
wheel nuts, and TPMS sensors for
your 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.
SeeChanging a Flat Tire on
page 5-69for more information.
Service and Appearance Care 5-53