transmission GMC ENVOY DENALI 2009 Owner's Manual

This light should come on
when the ignition is on, but
the engine is not running,
as a check to show it
working. If it does not,
have the vehicle serviced
by your dealer/retailer.
If the check engine light comes on and stays on, while
the engine is running, this indicates that there is an
OBD II problem and service is required.
Malfunctions often are indicated by the system before
any problem is apparent. Being aware of the light
can prevent more serious damage to the vehicle.
This system assists the service technician in correctly
diagnosing any malfunction.Notice:If the vehicle is continually driven with
this light on, after a while, the emission controls
might not work as well, the vehicle’s fuel economy
might not be as good, and the engine might not
run as smoothly. This could lead to costly repairs
that might not be covered by the vehicle warranty.
Notice:Modications made to the engine,
transmission, exhaust, intake, or fuel system of
the vehicle or the replacement of the original tires
with other than those of the same Tire Performance
Criteria (TPC) can affect the vehicle’s emission
controls and can cause this light to come on.
Modications to these systems could lead to
costly repairs not covered by the vehicle warranty.
This could also result in a failure to pass a
required Emission Inspection/Maintenance test.
SeeAccessories and Modifications on page 5-3.
3-39

SERVICE TIRE MONITOR
On vehicles with the Tire Pressure Monitor System
(TPMS), this message displays if a part on the TPMS is
not working properly. The tire pressure light also ashes
and then remains on during the same ignition cycle. See
Tire Pressure Light on page 3-38. Several conditions may
cause this message to appear. SeeTire Pressure Monitor
Operation on page 5-64for more information. If the
warning comes on and stays on, there may be a problem
with the TPMS. See your dealer/retailer.
STABILITRAK ACTIVE
This message displays anytime the StabiliTrak system
activates to maintain vehicle stability. Any combination
of engine speed management, brake traction control,
and stability control displays this message.
STABILITRAK NOT READY
This message may display if driving conditions delay
StabiliTrak system initialization. This is normal. Once the
system initializes, this message will no longer be
displayed on the DIC.
STABILITRAK OFF
This message displays when you press the StabiliTrak
button for more than ve seconds or when stability
control has been automatically disabled. The StabiliTrak
button is located on the transmission shift handle.
To limit wheel spin and realize the full benets of the
stability enhancement system, you should normally
leave StabiliTrak on. However, you should turn
StabiliTrak off if your vehicle gets stuck in sand, mud,
ice, or snow and you want to rock your vehicle to
attempt to free it, or if you are driving in extreme off-road
conditions and require more wheel spin. SeeIf Your
Vehicle is Stuck in Sand, Mud, Ice, or Snow on
page 4-30. To turn the StabiliTrak system back on,
press the StabiliTrak button again.
There are several conditions that can cause this
message to appear.
The message may display if the brake system
warning light is on. SeeBrake System Warning
Light on page 3-35.
The message displays if the vehicle is shifted
into 4LO.
The message turns off as soon as the conditions that
caused the message to be displayed are no longer
present.
3-55

TIGHTEN FUEL CAP
This message may display and a chime may sound if
the vehicle’s fuel cap is not tightened properly. Fully
reinstall the fuel cap. SeeFilling the Tank on page 5-8.
The diagnostic system can determine if the fuel cap
has been left off or improperly installed. A loose
or missing fuel cap allows fuel to evaporate into the
atmosphere. This message remains on until it is
manually cleared from the DIC display. The DIC
message is also cancelled if the ignition is turned off.
The DIC message and the Service Engine Soon light
may come on again during a second trip if the fuel cap is
still not tightened properly. SeeMalfunction Indicator
Lamp on page 3-38for more information.
TRACTION CONTROL OFF
This message displays when you momentarily press
the StabiliTrak button located on the transmission
shift handle. In this mode, stability control and the
brake-traction control are functional. Engine speed
management will be modied and the driven wheels can
spin more freely. For more details on this mode, see
StabiliTrak
®System on page 4-6.
TURN SIGNAL ON
This message displays and a chime sounds if a turn
signal is left on for 3/4 of a mile (1.2 km). Move the turn
signal/multifunction lever to the off position.
DIC Vehicle Customization
Your vehicle may have customization capabilities that
allow you to program some features to one setting
based on your preference. All of the customizable
options listed may not be available on your vehicle.
Only the options available display on the Driver
Information Center (DIC).
The default settings for the customization features were
set when your vehicle left the factory, but may have
been changed from their default state since then.
To change feature preferences, make sure the ignition
is on and the vehicle is in P (Park). To avoid excessive
drain on the battery, it is recommended that the
headlamps are turned off.
Press
4to scroll through the available customizable
options.
After pressing
4, VEHICLE SETTINGS momentarily
displays before going to a customization option.
3-56

When the StabiliTrak
system is both on and
actively controlling the
stability of the vehicle, the
StabiliTrak light will blink for
the duration of the event.
The system may be heard or felt while it is working.
This is normal.
The StabiliTrak disable
button is located on the
transmission shift handle.
The StabiliTrak system is automatically disabled in
4LO mode and cannot be turned on until the vehicle is
switched to 2HI, 4HI, or 4AWD.
The StabiliTrak system has three modes of operation:
STABILITRAK ON, TRACTION CONTROL OFF, and
STABILITRAK OFF.
STABILITRAK ON — The vehicle will default to
STABILITRAK ON every time the driver starts the
vehicle. The StabiliTrak light will be off and no DIC
messages will be displayed.TRACTION CONTROL OFF — The driver can modify
the engine speed management system by momentarily
pressing the StabiliTrak button on the transmission shift
handle. The StabiliTrak light will come on and TRACTION
CONTROL OFF will be displayed. For vehicles without
a DIC, the StabiliTrak indicator light will come on.
Momentarily pressing the StabiliTrak button again will
return the system to the STABILITRAK ON mode.
STABILITRAK OFF — The driver can turn off
StabiliTrak by pressing the StabiliTrak button for more
than ve seconds. The StabiliTrak light will come on
and STABILITRAK OFF will be displayed. For vehicles
without a DIC, the StabiliTrak indicator light will
come on. Momentarily pressing the StabiliTrak button
again will return the system to the STABILITRAK
ON mode. See StabiliTrak Off below for more
information.
Traction Control Off
In this mode, stability control and brake-traction control
are functional. Engine speed management will be
modied and the driven wheels can spin more freely.
This can cause the brake-traction control to activate
more frequently. If the controller detects excessive wheel
spin in this mode, the StabiliTrak indicator light may
blink and the STABILITRAK ACTIVE message may be
displayed to warn the driver that damage may occur
to the transfer case.
4-7

Vehicles with a DIC Vehicles without a DIC Event
Blinking StabiliTrak Active Blinking OffStabiliTrak system activates using
engine speed management, brake
traction control, and/or stability
control.
SolidService
StabiliTrakSolid SolidStabiliTrak system is disabled due to
a system fault.
SolidStabiliTrak Not
ReadySolid OffStabiliTrak system is disabled due to
a failure to initialize.
Notice:If the StabiliTrak
®light comes on due to
heavy braking and/or because the traction control
system has been continuously active, do not allow
the wheel(s) of one axle to spin excessively. This
could lead to damage to the transfer case and costly
repairs not covered by the vehicle warranty.
Notice:If the wheel(s) of one axle is allowed to spin
excessively while the StabiliTrak, ABS and brake
warning lights and any relevant DIC messages are
displayed, the transfer case could be damaged. The
repairs would not be covered by the vehicle warranty.
Reduce engine power and do not spin the wheel(s)
excessively while these lights and messages are
displayed.StabiliTrak may activate on dry or rough roads or under
conditions such as heavy acceleration while turning
or abrupt upshifts/downshifts of the transmission. When
this happens, a reduction in acceleration may be noticed,
or a noise or vibration may be heard. This is normal.
If cruise control is being used when the system activates,
the StabiliTrak light will ash and cruise control will
automatically disengage. Cruise control may be
reengaged when road conditions allow. SeeCruise
Control on page 3-10.
4-9

Attach a ag to the vehicle to be more visible to
approaching traffic on trails or hills.
Sound the horn as you approach the top of the hill
to let opposing traffic know you are there.
Use headlamps even during the day to make the
vehicle more visible to oncoming traffic.
{CAUTION:
Driving to the top (crest) of a hill at full speed can
cause an accident. There could be a drop-off,
embankment, cliff, or even another vehicle. You
could be seriously injured or killed. As you near
the top of a hill, slow down and stay alert.If the vehicle stalls, or is about to stall, and you cannot
make it up the hill:
Push the brake pedal to stop the vehicle and keep it
from rolling backwards and apply the parking brake.
If the engine is still running, shift the transmission to
R (Reverse), release the parking brake, and slowly
back down the hill in R (Reverse).
If the engine has stopped running, you need to
restart it. With the brake pedal pressed and the
parking brake still applied, shift the transmission
to P (Park) and restart the engine. Then, shift to
R (Reverse), release the parking brake, and slowly
back down the hill as straight as possible in
R (Reverse).
While backing down the hill, put your left hand on the
steering wheel at the 12 o’clock position so you can
tell if the wheels are straight and can maneuver as
you back down. It is best to back down the hill with
the wheels straight rather than in the left or right
direction. Turning the wheel too far to the left or right
will increase the possibility of a rollover.
4-19

Things not to do if the vehicle stalls, or is about to stall,
when going up a hill:
Never attempt to prevent a stall by shifting into
N (Neutral) to rev-up the engine and regain forward
momentum. This will not work. The vehicle can roll
backward very quickly and could go out of control.
Never try to turn around if about to stall when going
up a hill. If the hill is steep enough to stall the vehicle,
it is steep enough to cause it to roll over. If you
cannot make it up the hill, back straight down the hill.
If, after stalling, you try to back down the hill and decide
you just cannot do it, set the parking brake, put your
transmission in P (Park), and turn off the engine. Leave
the vehicle and go get some help. Exit on the uphill side
and stay clear of the path the vehicle would take if it rolled
downhill. Do not shift the transfer case to Neutral when
you leave the vehicle. Leave it in some gear.
{CAUTION:
Shifting the transfer case to Neutral can cause your
vehicle to roll even if the transmission is in P (Park).
This is because the Neutral position on the transfer
case overrides the transmission. You or someone
else could be injured. If you are going to leave
your vehicle, set the parking brake and shift the
transmission to P (Park). But do not shift the
transfer case to Neutral.
4-20

Driving Downhill
When off-roading takes you downhill, consider:
How steep is the downhill? Will I be able to maintain
vehicle control?
What is the surface like? Smooth? Rough?
Slippery? Hard-packed dirt? Gravel?
Are there hidden surface obstacles? Ruts? Logs?
Boulders?
What is at the bottom of the hill? Is there a hidden
creek bank or even a river bottom with large rocks?
If you decide you can go down a hill safely, try to keep
the vehicle headed straight down. Use a low gear
so engine drag can help the brakes so they do not have
to do all the work. Descend slowly, keeping the
vehicle under control at all times.
{CAUTION:
Heavy braking when going down a hill can cause
your brakes to overheat and fade. This could cause
loss of control and a serious accident. Apply the
brakes lightly when descending a hill and use a low
gear to keep vehicle speed under control.Things not to do when driving down a hill:
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too
steep to drive down might be too steep to drive
across. The vehicle could roll over.
Never go downhill with the transmission in
N (Neutral), called free-wheeling. The brakes
will have to do all the work and could overheat
and fade.
Vehicles are much more likely to stall when going uphill,
but if it happens when going downhill:
1. Stop the vehicle by applying the regular brakes and
apply the parking brake.
2. Shift to P (Park) and, while still braking, restart the
engine.
3. Shift back to a low gear, release the parking brake,
and drive straight down.
4. If the engine will not start, get out and get help.
4-21

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.
4-27

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