light GMC ENVOY 2008 Owners Manual

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. If you
do, you may be causing damage to the transfer case.
This could lead to costly repairs not covered by your
warranty.
Notice:If you allow the wheel(s) of one axle to spin
excessively while the StabiliTrak
®, ABS and brake
warning lights and the SERVICE STABILITRAK
message are displayed, you could damage the
transfer case. The repairs would not be covered by
your warranty. Reduce engine power and do not spin
the wheel(s) excessively while these lights and this
message 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, you may notice a reduction in
acceleration, or may hear a noise or vibration.
This is normal.If your vehicle is in cruise control when the system
activates, the StabiliTrak
®light will blink, and the
cruise control will automatically disengage. When
road conditions allow, you may re-engage the cruise
control. SeeCruise Control on page 3-11.
StabiliTrak
®will turn off automatically if a problem is
detected in the system. The StabiliTrak®light will come
on and SERVICE STABILITRAK will be displayed on
the DIC. For vehicles without a DIC, the StabiliTrak
®
light and the StabiliTrak®service light will both come on.
If the SERVICE STABILITRAK message (or StabiliTrak®
service light) does not clear itself after restarting the
vehicle, you should see your dealer for service.
Adding non-GM accessories can affect your vehicle’s
performance. SeeAccessories and Modifications
on page 5-3for more information.
4-9

Off-Road Recovery
You may nd that your right wheels have dropped off
the edge of a road onto the shoulder while you are
driving.
If the level of the shoulder is only slightly below the
pavement, recovery should be fairly easy. Ease off the
accelerator and then, if there is nothing in the way, steer
so that your vehicle straddles the edge of the pavement.
You can turn the steering wheel up to one-quarter turn
until the right front tire contacts the pavement edge. Then
turn the steering wheel to go straight down the roadway.
Passing
Passing another vehicle on a two-lane road can be
dangerous. To reduce the risk of danger while passing,
we suggest the following tips:
Look down the road, to the sides, and to crossroads
for situations that might affect a successful pass.
If in doubt, wait.
Watch for traffic signs, pavement markings, and
lines that could indicate a turn or an intersection.
Never cross a solid or double-solid line on your
side of the lane.
Do not get too close to the vehicle you want to
pass. Doing so can reduce your visibility.
Wait your turn to pass a slow vehicle.
When you are being passed, ease to the right.
Loss of Control
Let us review what driving experts say about what
happens when the three control systems — brakes,
steering, and acceleration — do not have enough friction
where the tires meet the road to do what the driver has
asked.
In any emergency, do not give up. Keep trying to steer
and constantly seek an escape route or area of less
danger.
4-12

Surface Obstacles:Unseen or hidden obstacles can
be hazardous. A rock, log, hole, rut, or bump can startle
you if you are not prepared for them. Often these
obstacles are hidden by grass, bushes, snow, or even
the rise and fall of the terrain itself. Here are some things
to consider:
Is the path ahead clear?
Will the surface texture change abruptly up ahead?
Does the travel take you uphill or downhill? There is
more discussion of these subjects later.
Will you have to stop suddenly or change direction
quickly?
When you drive over obstacles or rough terrain, keep a
rm grip on the steering wheel. Ruts, troughs, or other
surface features can jerk the wheel out of your hands if
you are not prepared.
When you drive over bumps, rocks, or other obstacles,
the wheels can leave the ground. If this happens,
even with one or two wheels, you cannot control the
vehicle as well or at all.Because you will be on an unpaved surface, it is
especially important to avoid sudden acceleration,
sudden turns, or sudden braking.
In a way, off-road driving requires a different kind of
alertness from driving on paved roads and highways.
There are no road signs, posted speed limits, or signal
lights. You have to use your own good judgment
about what is safe and what is not.
Drinking and driving can be very dangerous on any
road. And this is certainly true for off-road driving.
At the very time you need special alertness and driving
skills, your reexes, perceptions, and judgment can be
affected by even a small amount of alcohol. You could
have a serious — or even fatal — accident if you drink
and drive or ride with a driver who has been drinking.
SeeDrunk Driving on page 4-2.
4-17

Driving Downhill
When off-roading takes you downhill, you will want to
consider a number of things:
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, then try
to keep your vehicle headed straight down, and use a
low gear. This way, engine drag can help the brakes and
they will not have to do all the work. Descend slowly,
keeping your 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.There some things not to do when driving down a hill.
These are important because, if you ignore them,
you could lose control and have a serious accident:
When driving downhill, avoid turns that take you
across the incline of the hill. A hill that is not too steep
to drive down may be too steep to drive across. You
could roll over if you do not drive straight down.
Never go downhill with the transmission in
NEUTRAL (N). This is called “free-wheeling.”
The brakes will have to do all the work and could
overheat and fade.
Your vehicle is much more likely to stall when going
uphill. But if it happens when going downhill:
1. Stop your vehicle by applying the regular brakes.
Apply the parking brake.
2. Shift to PARK (P) 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

Driving at Night
Night driving is more dangerous than day driving
because some drivers are likely to be impaired — by
alcohol or drugs, with night vision problems, or by
fatigue.
Night driving tips include:
Drive defensively.
Do not drink and drive.
Reduce headlamp glare by adjusting the inside
rearview mirror.
Slow down and keep more space between you and
other vehicles because your headlamps can only
light up so much road ahead.
Watch for animals.
When tired, pull off the road.
Do not wear sunglasses.
Avoid staring directly into approaching headlamps.
Keep the windshield and all glass on your vehicle
clean — inside and out.
Keep your eyes moving, especially during turns or
curves.
No one can see as well at night as in the daytime.
But, as we get older, these differences increase.
A 50-year-old driver might need at least twice as much
light to see the same thing at night as a 20-year-old.
4-26

Driving in Rain and on Wet Roads
Rain and wet roads can reduce vehicle traction
and affect your ability to stop and accelerate. Always
drive slower in these types of driving conditions
and avoid driving through large puddles and
deep-standing or owing water.
{CAUTION:
Wet brakes can cause crashes. They might not
work as well in a quick stop and could cause
pulling to one side. You could lose control of
the vehicle.
After driving through a large puddle of water
or a car/vehicle wash, lightly apply the brake
pedal until the brakes work normally.
Flowing or rushing water creates strong
forces. Driving through owing water could
cause your vehicle to be carried away. If this
happens, you and other vehicle occupants
could drown. Do not ignore police warnings
and be very cautious about trying to drive
through owing water.
Hydroplaning
Hydroplaning is dangerous. Water can build up under
your vehicle’s tires so they actually ride on the water. This
can happen if the road is wet enough and you are going
fast enough. When your vehicle is hydroplaning, it has
little or no contact with the road.
There is no hard and fast rule about hydroplaning.
The best advice is to slow down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather driving tips
include:
Allow extra following distance.
Pass with caution.
Keep windshield wiping equipment in good shape.
Keep the windshield washer uid reservoir lled.
Have good tires with proper tread depth. SeeTires
on page 5-57.
4-27

Winter Driving
Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You might want to put winter emergency supplies in
your vehicle.
Include an ice scraper, a small brush or broom, a supply
of windshield washer uid, a rag, some winter outer
clothing, a small shovel, a ashlight, a red cloth, and
reective warning triangles. And, if you will be driving
under severe conditions, include a small bag of sand,
a piece of old carpet, or a couple of burlap bags to help
provide traction. Be sure you properly secure these
items in your vehicle.
Also seeTires on page 5-57.
Driving on Snow or Ice
Most of the time, those places where the tires meet the
road probably have good traction.
However, if there is snow or ice between the tires
and the road, you can have a very slippery situation.
You have a lot less traction, or grip, and need to be
very careful.What is the worst time for this? Wet ice. Very cold snow
or ice can be slick and hard to drive on. But wet ice can
be even more trouble because it can offer the least
traction of all. You can get wet ice when it is about
freezing, 32°F (0°C), and freezing rain begins to fall.
Try to avoid driving on wet ice until salt and sand crews
can get there.
Whatever the condition — smooth ice, packed, blowing,
or loose snow — drive with caution.
4-30

Run your engine only as long as you must. This saves
fuel. When you run the engine, make it go a little faster
than just idle. That is, push the accelerator slightly. This
uses less fuel for the heat that you get and it keeps the
battery charged. You will need a well-charged battery to
restart the vehicle, and possibly for signaling later on with
the headlamps. Let the heater run for a while.
Then, shut the engine off and close the window almost
all the way to preserve the heat. Start the engine again
and repeat this only when you feel really uncomfortable
from the cold. But do it as little as possible. Preserve the
fuel as long as you can. To help keep warm, you can get
out of the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
Slowly and cautiously spin the wheels to free your
vehicle when stuck in sand, mud, ice, or snow.
SeeRocking Your Vehicle to Get It Out on page 4-34.If your vehicle has a traction system, it can often help
to free a stuck vehicle. Refer to your vehicle’s traction
system in the Index. If the stuck condition is too
severe 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 your vehicle,
seeTire Chains on page 5-80.
4-33

Rocking Your Vehicle to Get It Out
First, 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. SeeStabiliTrak
®System on page 4-6.
Then shift back and forth between REVERSE (R) 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 you shift, and press lightly on the accelerator
pedal when the transmission is in gear. By slowly
spinning the wheels in the forward and reverse directions,
you will cause a rocking motion that could free your
vehicle. If that does not get your vehicle out after a few
tries, it might need to be towed out. If your vehicle does
need to be towed out, seeTowing Your Vehicle on
page 4-40.
Loading Your 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 your 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 your 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 your vehicle.
4-34

4. Follow the dolly manufacturer’s instructions to
attach and secure the vehicle being towed to
the dolly and then the loaded dolly to the tow
vehicle. Use an adequate clamping device to ensure
that the front wheels are locked into the straight
position.
5. Release the parking brake only after the vehicle
being towed is rmly attached to the towing
vehicle.
6. Turn the ignition to LOCK.
If the tow vehicle will not be started or driven for
six weeks or more, remove the battery cable
from the negative terminal (post) of the battery.
Electronically Controlled Air
Suspension System
Your vehicle may be equipped with an electronically
controlled air suspension system that automatically
keeps your vehicle level as you load and unload.
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. During this time, the
indicator light on the air inator switch will be ashing.
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.
You may hear the compressor operating when you load
your vehicle, 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.
4-44