2008 GMC ENVOY DENALI change time

XM™ Satellite Radio Service
XM™ Satellite Radio Service gives digital radio
reception from coast-to-coast in the 48 contiguous
United States, and in Canada. Just as with FM,
tall buildings or hills can interfere with satellite radio
signals, causing the sound to fade in and out. In
addition, traveling or standing under heavy foliage,
bridges, garages, or tunnels may cause loss of the XM™
signal for a period of time. The radio may display NO
SIGNAL to indicate interference.
Fixed Mast Antenna
The xed mast antenna can withstand most car washes
without being damaged. If the mast should ever become
slightly bent, straighten it out by hand. If the mast is badly
bent, replace it.
Check occasionally to make sure the mast is still
tightened to its base. If tightening is required, tighten
by hand, then with a wrench one quarter turn.
XM™ Satellite Radio Antenna
System
The XM™ Satellite Radio antenna is located on the roof
of your vehicle. Keep this antenna clear of snow and
ice build up for clear radio reception.
If your vehicle has a sunroof, the performance of the
XM™ system may be affected if the sunroof is open.
Loading items onto the roof of your vehicle can interfere
with the performance of the XM™ system. Make sure
the XM™ Satellite Radio antenna is not obstructed.
Chime Level Adjustment
The radio is used to adjust the vehicle’s chime level.
To change the volume level of the chime, press and hold
pushbutton 6 with the ignition on and the radio power off.
The volume level will change from the normal level to
loud, and LOUD CHIME will appear on the radio display.
To change back to the default or normal setting, press
and hold pushbutton 6 again. The volume level will
change from the loud level to normal, and NORMAL
CHIME will appear on the radio display. Removing the
radio and not replacing it with a factory radio or chime
module will disable vehicle chimes.
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Let us say the road is wet and you are driving safely.
Suddenly, an animal jumps out in front of you. You slam
on the brakes and continue braking. Here is what
happens with ABS:
A computer senses that wheels are slowing down.
If one of the wheels is about to stop rolling, the computer
will separately work the brakes at each front wheel
and at both rear wheels.
ABS can change the brake pressure faster than any
driver could. The computer is programmed to make
the most of available tire and road conditions. This
can help you steer around the obstacle while
braking hard.
As you brake, the computer keeps receiving updates on
wheel speed and controls braking pressure accordingly.
Remember: ABS does not change the time you need to
get your foot up to the brake pedal or always decrease
stopping distance. If you get too close to the vehicle in
front of you, you will not have time to apply the brakes
if that vehicle suddenly slows or stops. Always leave
enough room up ahead to stop, even though you
have ABS.Using ABS
Do not pump the brakes. Just hold the brake pedal
down rmly and let antilock work for you. You might
feel the brakes vibrate or notice some noise, but this
is normal.
Braking in Emergencies
With ABS, you can steer and brake at the same time.
In many emergencies, steering can help you more than
even the very best braking.
Locking Rear Axle
If your vehicle has this feature, your locking rear axle
can give you additional traction on snow, mud, ice,
sand or gravel. It works like a standard axle most of the
time, but when one of the rear wheels has no traction
and the other does, this feature will allow the wheel with
traction to move the vehicle.
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Getting Familiar with Off-Road Driving
It is a good idea to practice in an area that is safe
and close to home before you go into the wilderness.
Off-road driving does require some new and different
skills. Here is what we mean.
Tune your senses to different kinds of signals. Your
eyes, for example, need to constantly sweep the terrain
for unexpected obstacles. Your ears need to listen
for unusual tire or engine sounds. With your arms,
hands, feet, and body, you will need to respond to
vibrations and vehicle bounce.
Controlling your vehicle is the key to successful off-road
driving. One of the best ways to control your vehicle
is to control your speed. Here are some things to keep
in mind. At higher speeds:
You approach things faster and you have less time
to scan the terrain for obstacles.
You have less time to react.
You have more vehicle bounce when you drive over
obstacles.
You will need more distance for braking, especially
since you are on an unpaved surface.
{CAUTION:
When you are driving off-road, bouncing and
quick changes in direction can easily throw
you out of position. This could cause you to
lose control and crash. So, whether you are
driving on or off the road, you and your
passengers should wear safety belts.
Scanning the Terrain
Off-road driving can take you over many different kinds
of terrain. You need to be familiar with the terrain and its
many different features. Here are some things to
consider.
Surface Conditions:Off-roading can take you over
hard-packed dirt, gravel, rocks, grass, sand, mud, snow,
or ice. Each of these surfaces affects the steering,
acceleration, and braking of your vehicle in different
ways. Depending upon the kind of surface you are on,
you may experience slipping, sliding, wheel spinning,
delayed acceleration, poor traction, and longer braking
distances.
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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.
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Trailering is different than just driving your vehicle by
itself. Trailering means changes in acceleration, braking,
handling, durability and fuel economy. Successful,
safe trailering takes correct equipment, and it has to
be used properly.
That’s the reason for this part. In it are many
time-tested, important trailering tips and safety rules.
Many of these are important for your safety and that of
your passengers. So please read this section carefully
before you pull a trailer.
If You Do Decide To Pull A Trailer
If you do, here are some important points:
There are many different laws, including speed limit
restrictions, having to do with trailering. Make sure
your rig will be legal, not only where you live but also
where you’ll be driving. A good source for this
information can be state or provincial police.
Consider using a sway control. See “Hitches” later in
this section.
Don’t tow a trailer at all during the rst 500 miles
(800 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
Then, during the rst 500 miles (800 km) that you tow
a trailer, don’t drive over 50 mph (80 km/h) and don’t
make starts at full throttle. This helps your engine
and other parts of your vehicle wear in at the heavier
loads.
You can tow in DRIVE (D). You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often
(e.g., under heavy loads and/or hilly conditions).
Three important considerations have to do with weight:
the weight of the trailer,
the weight of the trailer tongue
and the weight on your vehicle’s tires.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig. For example,
speed, altitude, road grades, outside temperature and
how much your vehicle is used to pull a trailer are all
important. It can also depend on any special equipment
that you have on your vehicle, and the amount of tongue
weight the vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.
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Look for this information on the oil container, and
use only those oils that are identied as meeting
GM Standard GM6094M and have the starburst
symbol on the front of the oil container.
Notice:Use only engine oil identied as meeting
GM Standard GM6094M and showing the American
Petroleum Institute Certied For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both provide easier
cold starting and better protection for the engine at
extremely low temperatures.
Engine Oil Additives
Do not add anything to the oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all you need for good performance
and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and lter. This is based
on engine revolutions and engine temperature, and not
on mileage. Based on driving conditions, the mileage
at which an oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is necessary.
A change engine oil light will come on, and, if your vehicle
has a Driver Information Center (DIC), a CHANGE
ENGINE OIL message will come on. See the oil as soon
as possible within the next 600 miles (1 000 km).
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It is possible that, if you are driving under the best
conditions, the oil life system might not indicate that an oil
change is necessary for over a year. However, the engine
oil and lter must be changed at least once a year and at
this time the system must be reset. Your dealer/retailer
has trained people who will perform this work using
genuine parts and reset the system. It is also important to
check the oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must
change the oil at 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system whenever
the oil is changed.
How to Reset the Engine Oil Life
System
The Engine Oil Life System calculates when to change
the engine oil and lter based on vehicle use.
Whenever the oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change the oil prior
to a change engine oil light or CHANGE ENGINE OIL
message being turned on, reset the system.To reset the Engine Oil Life System:
1. Turn the ignition key to ON/RUN with the
engine off.
2. Fully press and release the accelerator pedal slowly
three times within ve seconds.
The change engine oil light will ash while the
system is resetting.
3. When the light stops ashing, turn the key to
LOCK/OFF.
If the light/message comes back on when you start the
vehicle, the engine oil life system has not reset.
Repeat the procedure.
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Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
A good time to check your automatic transmission uid
level is when the engine oil is changed.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the transmission uid listed inRecommended
Fluids and Lubricants on page 6-12.
How to Check Automatic Transmission
Fluid
Because this operation can be a little difficult, you may
choose to have this done at the dealer/retailer service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
parts or exhaust system parts, starting a re. Too
little uid could cause the transmission to overheat.
Be sure to get an accurate reading if you check your
transmission uid.Wait at least 30 minutes before checking the
transmission uid level if you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic — especially in hot weather.
While pulling a trailer.
To get the right reading, the uid should be at normal
operating temperature, which is 180°F to 200°F
(82°C to 93°C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it is colder than 50°F (10°C), drive the vehicle
in THIRD (3) until the engine temperature gage moves
and then remains steady for 10 minutes.
A cold uid check can be made after the vehicle has
been sitting for eight hours or more with the engine off,
but this is used only as a reference. Let the engine
run at idle for ve minutes if outside temperatures are
50°F (10°C) or more. If it is colder than 50°F (10°C), you
may have to idle the engine longer. Should the uid
level be low during this cold check, you must check the
uid hot before adding uid. Checking the uid hot will
give you a more accurate reading of the uid level.
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