GMC ENVOY 2009 Owner's Manual

Hill and Mountain Roads
Driving on steep hills or through mountains is different
than driving on at or rolling terrain. Tips for driving
in these conditions include:
Keep the vehicle serviced and in good shape.
Check all uid levels and brakes, tires, cooling
system, and transmission.
Going down steep or long hills, shift to a
lower gear.
{CAUTION:
If you do not shift down, the brakes could get so
hot that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Shift down to let the engine
assist the brakes on a steep downhill slope.
{CAUTION:
Coasting downhill in N (Neutral) or with the ignition
off is dangerous. The brakes will have to do all the
work of slowing down and they could get so hot
that they would not work well. You would then
have poor braking or even none going down a hill.
You could crash. Always have the engine running
and the vehicle in gear when going downhill.
Stay in your own lane. Do not swing wide or cut
across the center of the road. Drive at speeds
that let you stay in your own lane.
Top of hills: Be alert — something could be in your
lane (stalled car, accident).
Pay attention to special road signs (falling rocks
area, winding roads, long grades, passing or
no-passing zones) and take appropriate action.
SeeOff-Road Driving on page 4-13for information
about driving off-road.
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Winter Driving
Driving on Snow or Ice
Drive carefully when there is snow or ice between the
tires and the road, creating less traction or grip. Wet ice
can occur at about 32°F (0°C) when freezing rain
begins to fall, resulting in even less traction. Avoid
driving on wet ice or in freezing rain until roads can be
treated with salt or sand.
Drive with caution, whatever the condition. Accelerate
gently so traction is not lost. Accelerating too quickly
causes the wheels to spin and makes the surface under
the tires slick, so there is even less traction.
Try not to break the fragile traction. If you accelerate too
fast, the drive wheels will spin and polish the surface
under the tires even more.
TheAntilock Brake System (ABS) on page 4-5improves
vehicle stability during hard stops on a slippery roads, but
apply the brakes sooner than when on dry pavement.
Allow greater following distance on any slippery road
and watch for slippery spots. Icy patches can occur on
otherwise clear roads in shaded areas. The surface
of a curve or an overpass can remain icy when the
surrounding roads are clear. Avoid sudden steering
maneuvers and braking while on ice.
Turn off cruise control, if equipped, on slippery surfaces.
Blizzard Conditions
Being stuck in snow can be in a serious situation. Stay
with the vehicle unless there is help nearby. If possible,
use theRoadside Assistance Program on page 7-7.
To get help and keep everyone in the vehicle safe:
Turn on theHazard Warning Flashers on page 3-6.
Tie a red cloth to an outside mirror.
{CAUTION:
Snow can trap engine exhaust under the vehicle.
This may cause exhaust gases to get inside.
Engine exhaust contains carbon monoxide (CO)
which cannot be seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in the snow:
Clear away snow from around the base of
your vehicle, especially any that is blocking
the exhaust pipe.
Check again from time to time to be sure
snow does not collect there.
CAUTION: (Continued)
4-28

CAUTION: (Continued)

Open a window about two inches (5 cm) on
the side of the vehicle that is away from the
wind to bring in fresh air.
Fully open the air outlets on or under the
instrument panel.
Adjust the Climate Control system to a setting
that circulates the air inside the vehicle and
set the fan speed to the highest setting. See
Climate Control System in the Index.
For more information about carbon monoxide, see
Engine Exhaust on page 2-37.
Snow can trap exhaust gases under your vehicle.
This can cause deadly CO (carbon monoxide) gas
to get inside. CO could overcome you and kill you.
You cannot see it or smell it, so you might not
know it is in your vehicle. Clear away snow from
around the base of your vehicle, especially any
that is blocking the exhaust.Run the engine for short periods only as needed to
keep warm, but be careful.
To save fuel, run the engine for only short periods as
needed to warm the vehicle and then shut the engine
off and close the window most of the way to save heat.
Repeat this until help arrives but only when you feel
really uncomfortable from the cold. Moving about
to keep warm also helps.
If it takes some time for help to arrive, now and then when
you run the engine, push the accelerator pedal slightly so
the engine runs faster than the idle speed. This keeps the
battery charged to restart the vehicle and to signal for
help with the headlamps. Do this as little as possible to
save fuel.
4-29

If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
Slowly and cautiously spin the wheels to free the
vehicle when stuck in sand, mud, ice, or snow. See
Rocking Your Vehicle to Get It Out on page 4-31.
If the vehicle has a traction system, it can often help
to free a stuck vehicle. Refer to the vehicle’s traction
system in the Index. If stuck too severely for the traction
system to free the vehicle, turn the traction system off
and use the rocking method.
{CAUTION:
If you let your vehicle’s tires spin at high speed,
they can explode, and you or others could be
injured. The vehicle can overheat, causing an
engine compartment re or other damage. Spin the
wheels as little as possible and avoid going above
35 mph (55 km/h) as shown on the speedometer.
For information about using tire chains on the vehicle,
seeTire Chains on page 5-76.
4-30

Rocking Your Vehicle to Get It Out
Turn the steering wheel left and right to clear the
area around the front wheels. For four-wheel-drive
vehicles, shift into Four-Wheel High. Turn off any
traction or stability system. Shift back and forth between
R (Reverse) and a forward gear, spinning the wheels as
little as possible. To prevent transmission wear, wait until
the wheels stop spinning before shifting gears. Release
the accelerator pedal while shifting, and press lightly on
the accelerator pedal when the transmission is in gear.
Slowly spinning the wheels in the forward and reverse
directions causes a rocking motion that could free the
vehicle. If that does not get the vehicle out after a few
tries, it might need to be towed out. If the vehicle does
need to be towed out, seeTowing Your Vehicle on
page 4-38.
Loading the Vehicle
It is very important to know how much weight your
vehicle can carry. This weight is called the vehicle
capacity weight and includes the weight of all
occupants, cargo, and all nonfactory-installed
options. Two labels on your vehicle show how much
weight it was designed to carry, the Tire and
Loading Information label and the Certication/Tire
label.
{CAUTION:
Do not load the vehicle any heavier than the
Gross Vehicle Weight Rating (GVWR), or
either the maximum front or rear Gross Axle
Weight Rating (GAWR). If you do, parts on the
vehicle can break, and it can change the way
your vehicle handles. These could cause you
to lose control and crash. Also, overloading
can shorten the life of the vehicle.
4-31

Tire and Loading Information Label
A vehicle specic Tire and Loading Information
label is attached to the center pillar (B-pillar).
With the driver’s door open, you will nd the
label attached below the door lock post (striker).The Tire and Loading Information label shows the
number of occupant seating positions (A), and the
maximum vehicle capacity weight (B) in kilograms
and pounds.
The Tire and Loading Information label also shows
the size of the original equipment tires (C) and
the recommended cold tire ination pressures (D).
For more information on tires and ination see
Tires on page 5-53andInflation - Tire Pressure on
page 5-60.
There is also important loading information on the
vehicle Certication/Tire label. It tells you the
Gross Vehicle Weight Rating (GVWR) and
the Gross Axle Weight Rating (GAWR) for the
front and rear axle. See “Certication/Tire Label”
later in this section.
Label Example
4-32

Steps for Determining Correct Load Limit
1.Locate the statement “The combined weight
of occupants and cargo should never exceed
XXX kg or XXX lbs” on your vehicle’s placard.
2.Determine the combined weight of the driver
and passengers that will be riding in your
vehicle.
3.Subtract the combined weight of the driver
and passengers from XXX kg or XXX lbs.
4.The resulting gure equals the available
amount of cargo and luggage load capacity.
For example, if the “XXX” amount equals
1400 lbs and there will be ve 150 lb
passengers in your vehicle, the amount of
available cargo and luggage load capacity is
650 lbs (1400−750 (5 x 150) = 650 lbs).
5.Determine the combined weight of luggage
and cargo being loaded on the vehicle. That
weight may not safely exceed the available
cargo and luggage load capacity calculated
in Step 4.
6.If your vehicle will be towing a trailer, the load
from your trailer will be transferred to your
vehicle. Consult this manual to determine how
this reduces the available cargo and luggage
load capacity of your vehicle. SeeTowing
a Trailer on page 4-46for important
information on towing a trailer, towing safety
rules and trailering tips.
4-33

Item Description Total
AVehicle Capacity
Weight for
Example 1=1,000 lbs
(453 kg)
BSubtract Occupant
Weight 150 lbs
(68 kg)×2=300 lbs (136 kg)
CAvailable Occupant
and Cargo Weight=700 lbs (317 kg)Item Description Total
AVehicle Capacity
Weight for
Example 2=1,000 lbs
(453 kg)
BSubtract Occupant
Weight 150 lbs
(68 kg)×5=750 lbs (136 kg)
CAvailable Cargo
Weight=250 lbs (113 kg)
Example 1Example 2
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Item Description Total
AVehicle Capacity
Weight for
Example 3=1,000 lbs
(453 kg)
BSubtract Occupant
Weight 200 lbs
(91 kg)×5=1,000 lbs
(453 kg)
CAvailable Cargo
Weight=0 lbs (0 kg)Refer to your vehicle’s Tire and Loading
Information label for specic information about
your vehicle’s capacity weight and seating
positions. The combined weight of the driver,
passengers, and cargo should never exceed your
vehicle’s capacity weight.
Your vehicle may have an electronically controlled
air suspension system that automatically keeps
your vehicle level as you load and unload your
vehicle. SeeElectronically Controlled Air
Suspension System on page 4-45for additional
information.
Example 3
4-35

Certication/Tire Label
A vehicle specic Certication/Tire label is found on
the rear edge of the driver’s door. The label shows
the size of your vehicle’s original tires and the
ination pressures needed to obtain the gross
weight capacity of your vehicle. This is called Gross
Vehicle Weight Rating (GVWR). The GVWR
includes the weight of the vehicle, all occupants,
fuel, cargo, and trailer tongue weight, if pulling a
trailer.The Certication/Tire label also tells you the
maximum weights for the front and rear axles,
called Gross Axle Weight Rating (GAWR). To nd
out the actual loads on your front and rear axles,
you need to go to a weigh station and weigh your
vehicle. Your dealer can help you with this. Be sure
to spread out your load equally on both sides of the
centerline.
Never exceed the GVWR for your vehicle, or the
GAWR for either the front or rear axle.
And, if you do have a heavy load, you should
spread it out.
Similar appearing vehicles may have different
GVWRs and capacity weights. Please note your
vehicle’s Certication/Tire label or consult
your dealer for additional details.
4-36