2009 GMC ENVOY height

Head Restraints
Adjust the head restraint so that the top of the restraint
is at the same height as the top of the occupant’s
head. This position reduces the chance of a neck injury
in a crash.Pull the head restraint up
to raise it.
To lower the head restraint, press the button, located
on the top of the seatback, and push the head
restraint down.
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The manufacturer’s instructions that come with the
booster seat state the weight and height limitations for
that booster. Use a booster seat with a lap-shoulder belt
until the child passes the below t test:
Sit all the way back on the seat. Do the knees bend
at the seat edge? If yes, continue. If no, return to
the booster seat.
Buckle the lap-shoulder belt. Does the shoulder belt
rest on the shoulder? If yes, continue. If no, try
using the rear safety belt comfort guide. See “Rear
Safety Belt Comfort Guides” underLap-Shoulder
Belt on page 1-27for more information. If the
shoulder belt still does not rest on the shoulder,
then return to the booster seat.
Does the lap belt t low and snug on the hips,
touching the thighs? If yes, continue. If no, return to
the booster seat.
Can proper safety belt t be maintained for the
length of the trip? If yes, continue. If no, return
to the booster seat.
If you have the choice, a child should sit in a
position with a lap-shoulder belt and get the
additional restraint a shoulder belt can provide.
Q:What is the proper way to wear safety belts?
A:An older child should wear a lap-shoulder belt and
get the additional restraint a shoulder belt can
provide. The shoulder belt should not cross the face
or neck. The lap belt should t snugly below the
hips, just touching the top of the thighs. This applies
belt force to the child’s pelvic bones in a crash. It
should never be worn over the abdomen, which
could cause severe or even fatal internal injuries in
a crash.
Also see “Rear Safety Belt Comfort Guides” under
Lap-Shoulder Belt on page 1-27.
According to accident statistics, children and infants are
safer when properly restrained in a child restraint
system or infant restraint system secured in a rear
seating position.
In a crash, children who are not buckled up can strike
other people who are buckled up, or can be thrown
out of the vehicle. Older children need to use safety
belts properly.
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Q:What are the different types of add-on child
restraints?
A:Add-on child restraints, which are purchased by the
vehicle’s owner, are available in four basic types.
Selection of a particular restraint should take
into consideration not only the child’s weight, height,
and age but also whether or not the restraint will
be compatible with the motor vehicle in which it will
be used.
For most basic types of child restraints, there are
many different models available. When purchasing a
child restraint, be sure it is designed to be used
in a motor vehicle. If it is, the restraint will have a
label saying that it meets federal motor vehicle
safety standards.
The restraint manufacturer’s instructions that come
with the restraint state the weight and height
limitations for a particular child restraint. In addition,
there are many kinds of restraints available for
children with special needs.
{CAUTION:
To reduce the risk of neck and head injury during
a crash, infants need complete support. This is
because an infant’s neck is not fully developed
and its head weighs so much compared with the
rest of its body. In a crash, an infant in a
rear-facing child restraint settles into the restraint,
so the crash forces can be distributed across the
strongest part of an infant’s body, the back and
shoulders. Infants should always be secured in
rear-facing child restraints.
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Adding Equipment to Your
Airbag-Equipped Vehicle
Q:Is there anything I might add to or change
about the vehicle that could keep the airbags
from working properly?
A:Yes. If you add things that change your vehicle’s
frame, bumper system, height, front end or side
sheet metal, they may keep the airbag system from
working properly. Changing or moving any parts of
the front seats, safety belts, the airbag sensing and
diagnostic module, steering wheel, instrument panel,
roof-rail airbag modules, ceiling headliner or pillar
garnish trim, rearview mirror, front sensors, rollover
sensor module, or airbag wiring can affect the
operation of the airbag system.
In addition, your vehicle has a passenger sensing
system for the right front passenger’s position, which
includes sensors that are part of the passenger’s
seat. The passenger sensing system may not
operate properly if the original seat trim is replaced
with non-GM covers, upholstery or trim, or with GM
covers, upholstery or trim designed for a different
vehicle. Any object, such as an aftermarket seat
heater or a comfort enhancing pad or device,
installed under or on top of the seat fabric, could alsointerfere with the operation of the passenger sensing
system. This could either prevent proper deployment
of the passenger airbag(s) or prevent the passenger
sensing system from properly turning off the
passenger airbag(s). SeePassenger Sensing
System on page 1-64.
If you have any questions about this, you should
contact Customer Assistance before you modify
your vehicle. The phone numbers and addresses for
Customer Assistance are in Step Two of the
Customer Satisfaction Procedure in this manual.
SeeCustomer Satisfaction Procedure on page 7-2.
If your vehicle has rollover roof-rail airbags, see
Different Size Tires and Wheels on page 5-72
for additional important information.
Q:Because I have a disability, I have to get my
vehicle modied. How can I nd out whether this
will affect my airbag system?
A:If you have questions, call Customer Assistance.
The phone numbers and addresses for Customer
Assistance are in Step Two of the Customer
Satisfaction Procedure in this manual. SeeCustomer
Satisfaction Procedure on page 7-2.
In addition, your dealer/retailer and the service manual
have information about the location of the airbag sensors,
sensing and diagnostic module and airbag wiring.
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Electronically Controlled Air
Suspension System
With this feature, an electronically controlled air
suspension system automatically keeps the vehicle level
as it is loaded and unloaded. The system includes a
compressor, two height sensors and two air springs
supporting the rear axle.
The system also has an internal clock to prevent
overheating if the inator is used for prolonged periods.
If the system overheats, all leveling function stops
until the system cools down.
The ignition has to be on for the system to inate, in
order to raise the vehicle to the standard ride height after
loading. The system can lower the vehicle to the standard
ride height after unloading with the ignition on and also for
up to 30 minutes after the ignition has been turned off.
The compressor may be heard while it is operating when
the vehicle is being loaded, and periodically as the
system adjusts the vehicle to the standard ride height.
Load leveling will not function normally with the
inator hose attached to the inator outlet. Remove the
inator hose from the outlet during loading and
unloading.
If the vehicle is parked for an extended period of time,
some bleed down of the suspension is normal. Upon
starting the vehicle, proper height will be achieved.
Overload Protection
The air suspension system is equipped with overload
protection. Overload protection is designed to protect
the air suspension system, and it is an indicator to the
driver that the vehicle is overloaded. When the overload
protection mode is on, it will not allow damage to the
air compressor. However, do not overload the vehicle.
SeeLoading the Vehicle on page 4-31.
If the suspension remains at a low height, the rear
axle load has exceeded GAWR (Gross Axle Weight
Rating). When the overload protection mode is activated,
the compressor operates for about 30 seconds to one
minute without raising the vehicle depending on the
amount of overload. This will continue each time
the ignition is turned on until the rear axle load is
reduced below GAWR.
Indicator Light
The indicator light on the inator switch in the rear
passenger compartment also serves as an indicator for
internal system error. If the indicator light is ashing
without the load leveling function or the inator being
active, turn off the ignition. The next day turn on
the ignition and check the indicator light. The vehicle
can be driven with the light ashing, but if it is, the
vehicle should be serviced as soon as possible.
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Brake Wear
This vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads
are needed. The sound can come and go or be heard all
the time the vehicle is moving, except when applying
the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that soon
the brakes will not work well. That could lead to an
accident. When the brake wear warning sound is
heard, have the vehicle serviced.
Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly applied.
This does not mean something is wrong with the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specications in
Capacities and Specifications on page 5-120.
Brake linings should always be replaced as complete
axle sets.Brake Pedal Travel
See your dealer/retailer if the brake pedal does not
return to normal height, or if there is a rapid increase in
pedal travel. This could be a sign that brake service
might be required.
Brake Adjustment
Every brake stop, the disc brakes adjust for wear.
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Low-Prole Performance Tire
If your vehicle has P255/50R20 size tires, they
are classied as low-prole performance tires.
These tires are designed for very responsive
driving on wet or dry pavement. You may
also notice more road noise with low-prole
performance tires and that they tend to wear
faster.
Notice:If the vehicle has low-prole tires,
they are more susceptible to damage from road
hazards or curb impact than standard prole
tires. Tire and/or wheel assembly damage
can occur when coming into contact with
road hazards like, potholes, or sharp edged
objects, or when sliding into a curb. The
vehicle warranty does not cover this type of
damage. Keep tires set to the correct ination
pressure and, when possible avoid contact
with curbs, potholes, and other road hazards.
Tire Sidewall Labeling
Useful information about a tire is molded into the
sidewall. The following illustration is an example
of a typical P-Metric tire sidewall.
(A) Tire Size
:The tire size code is a combination
of letters and numbers used to dene 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.
Passenger (P-Metric) Tire
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Tire Size
The following examples show the different parts of
a 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 75, as
shown in item C of the passenger (P-Metric) tire
illustration, it would mean that the tire’s sidewall is
75 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
:The service description
indicates the load range and speed rating of a
tire. The load index can range from 1 to 279.
Speed ratings range from A to Z.
Passenger (P-Metric) Tire
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