2008 CHEVROLET TAHOE key

If the shift stabilization feature determines that a current
vehicle speed cannot be maintained, the transmission
does not upshift and instead holds the current gear.
In some cases, this could appear to be a delayed shift,
however the transmission is operating normally.
Your vehicle’s transmission uses adaptive shift controls.
Adaptive shift controls continually compares key shift
parameters to pre-programmed ideal shifts stored in the
transmissions computer. The transmission constantly
makes adjustments to improve vehicle performance
according to how the vehicle is being used, such as
with a heavy load or when temperature changes.
During this adaptive shift control process, shifting
might feel different as the transmission determines
the best settings.
When temperatures are very cold, the Allison
Transmission
®and Hydra-Matic®6-Speed
transmission’s gear shifting could be delayed providing
more stable shifts until the engine warms up. Shifts
could be more noticeable with a cold transmission.
This difference in shifting is normal.MANUAL MODE (M):This position, is available on
vehicles with the Allison Transmission
®or Hydra-Matic®
6-Speed transmission. It lets drivers select the range
of gears appropriate for current driving conditions. If your
vehicle has this feature, see Range Select Mode
(Allison Transmission
®or Hydra-Matic®6-Speed
transmission) later in this section.
THIRD (3):This position is also used for normal driving.
It reduces vehicle speed more than DRIVE (D) without
using the brakes. You might choose THIRD (3)
instead of DRIVE (D) when driving on hilly, winding
roads, when towing a trailer, so there is less shifting
between gears and when going down a steep hill.
SECOND (2):This position reduces vehicle speed even
more than THIRD (3) without using your brakes. You can
use SECOND (2) on hills. It can help control your speed
as you go down steep mountain roads, but then you
would also want to use the brakes off and on.
If you manually select SECOND (2) in an automatic
transmission, the transmission will start in second gear.
You can use this feature for reducing the speed of the
rear wheels when you are trying to start your vehicle from
a stop on slippery road surfaces.
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Shifting Into Park
{CAUTION:
It can be dangerous to get out of your vehicle
if the shift lever is not fully in PARK (P) with
the parking brake rmly set. Your vehicle can
roll. If you have left the engine running, the
vehicle can move suddenly. You or others
could be injured. To be sure your vehicle will
not move, even when you are on fairly level
ground, use the steps that follow. With
four-wheel drive, if your transfer case is in
NEUTRAL, your vehicle will be free to roll,
even if your shift lever is in PARK (P). So, be
sure the transfer case is in a drive gear — not
in NEUTRAL. If you are pulling a trailer, see
Towing a Trailer on page 4-49.
1. Hold the brake pedal down with your right foot and
set the parking brake.
SeeParking Brake on page 2-42for more
information.2. Move the shift lever into the PARK (P) position by
pulling the shift lever toward you and moving it up
as far as it will go.
3. Be sure the transfer case is in a drive gear — not
in NEUTRAL (N).
4. Turn the ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can
leave your vehicle with the ignition key in your
hand, your vehicle is in PARK (P).
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Shifting Out of Park
This vehicle is equipped with an electronic shift lock
release system. The shift lock release is designed to:
Prevent ignition key removal unless the shift
lever is in PARK (P) with the shift lever button
fully released, and
Prevent movement of the shift lever out of
PARK (P), unless the ignition is in ON/RUN or
ACC/ACCESSORY and the regular brake pedal
is applied.
The shift lock release is always functional except
in the case of an uncharged or low voltage (less
than 9 volt) battery.
If your vehicle has an uncharged battery or a battery
with low voltage, try charging or jump starting the
battery. SeeJump Starting on page 5-48for more
information.
To shift out of PARK (P) use the following:
1. Apply the brake pedal.
2. Move the shift lever to the desired position.If you still are unable to shift out of PARK (P):
1. Ease the pressure on the shift lever.
2. While holding down the brake pedal, press the shift
lever all the way into PARK (P).
3. Move the shift lever to the desired position.
If you are still having a problem shifting, then have your
vehicle serviced soon.
Parking Over Things That Burn
{CAUTION:
Things that can burn could touch hot exhaust
parts under your vehicle and ignite. Do not
park over papers, leaves, dry grass, or other
things that can burn.
2-45

OnStar®System
OnStar uses several innovative technologies and live
advisors to provide you with a wide range of safety,
security, information, and convenience services. If your
airbags deploy, the system is designed to make an
automatic call to OnStar Emergency advisors who can
request emergency services be sent to your location.
If you lock your keys in the vehicle, call OnStar at
1-888-4-ONSTAR and they can send a signal to unlock
your doors. If you need roadside assistance, press
the OnStar button and they can contact Roadside
Service for you.
OnStar service is provided to you subject to the OnStar
Terms and Conditions. You may cancel your OnStar
service at any time by contacting OnStar. A completeOnStar Owner’s Guide and the OnStar Terms and
Conditions are included in the vehicle’s OnStar
Subscriber glove box literature. For more information,
visit onstar.com or onstar.ca, contact OnStar
at 1-888-4-ONSTAR (1-888-466-7827) or TTY
1-877-248-2080, or press the OnStar button to speak
with an OnStar advisor 24 hours a day, 7 days a week.
Not all OnStar features are available on all vehicles.
To check if your vehicle is equipped to provide the
services described below, or for a full description of
OnStar services and system limitations, see the OnStar
Owner’s Guide in your glove box or visit onstar.com.
OnStar Services
For new vehicles with OnStar, the Safe & Sound Plan,
or the Directions & Connections Plan is included for
one year from the date of purchase. You can extend
this plan beyond the rst year, or upgrade to the
Directions & Connections Plan. For more information,
press the OnStar button to speak with an advisor.
Some OnStar services (such as Remote Door Unlock
or Stolen Vehicle Location Assistance) may not be
available until you register with OnStar.
2-59

Hazard Warning Flashers
The hazard warning ashers warn others. They also let
the police and other emergency vehicles know you
have a problem.
The hazard warning
asher button is located
on top of the steering
column.
Press the button to make the front and rear turn signal
lamps ash on and off. Press the button again to
turn the ashers off.
The hazard warning ashers work no matter what
ignition position the key is in, and even if the key is not
in the ignition.
When the hazard warning ashers are on, your vehicle’s
turn signals will not work.
Other Warning Devices
If you carry reective triangles, you can set them up at
the side of the road about 300 feet (100 m) behind
your vehicle.
Horn
To sound the horn, press the center pad on the steering
wheel.
Tilt Wheel
Your vehicle has a tilt wheel, that lets you adjust the
steering wheel before driving. Raising it to the highest
level gives more room to exit and enter your vehicle.
The tilt steering wheel lever is located on the lower left
side of the column.
To tilt the wheel, hold the steering wheel and pull the
lever. Then move the steering wheel to a comfortable
position and release the lever to lock the wheel in place.
3-6

Dome Lamp Override
The dome lamp override button is located next to the
exterior lamps control.
k(Dome Off):Press the button in and the dome
lamps remain off when a door is opened. Press
the button again to return it to the extended position so
that the dome lamps come on when a door is opened.
Entry Lighting
Your vehicle has an illuminated entry feature.
When the doors are opened, the dome lamps will come
on if the dome override button is in the extended
position. If the dome override button is pressed in, the
lamps will not come on.
Exit Lighting
The interior lamps come on when the key is removed
from the ignition. They turn off automatically in
20 seconds. The lights do not come on if the dome
override button is pressed in.
Reading Lamps
If your vehicle has reading lamps they are located on
the overhead console.To turn on the reading lamps, press the button
located next to each lamp. To turn them off, press the
button again.
Your vehicle may also have reading lamps in other
locations. To turn the lamps on or off, press the button
located next to the lamp.
The lamps are xed and cannot be adjusted.
Electric Power Management
The vehicle has Electric Power Management (EPM)
that estimates the battery’s temperature and state
of charge. It then adjusts the voltage for best
performance and extended life of the battery.
When the battery’s state of charge is low, the voltage is
raised slightly to quickly put the charge back in. When
the state of charge is high, the voltage is lowered slightly
to prevent overcharging. If the vehicle has a voltmeter
gage or a voltage display on the Driver Information
Center (DIC), you may see the voltage move up
or down. This is normal. If there is a problem, an alert
will be displayed.
The battery can be discharged at idle if the electrical
loads are very high. This is true for all vehicles.
This is because the generator (alternator) may not be
spinning fast enough at idle to produce all the power
that is needed for very high electrical loads.
3-19

Charging System Light
This light will come on
briey when you turn on
the ignition key, but
the engine is not running,
as a check to show
you it is working.
It should go out once the engine is running. If it stays
on, or comes on while driving, there could be a problem
with the charging system. A charging system Driver
Information Center (DIC) message may also appear.
SeeDIC Warnings and Messages on page 3-59
for more information. This light could indicate that there
are problems with a generator drive belt, or that
there is an electrical problem. Have it checked right
away. If you must drive a short distance with the light on,
be certain to turn off all the accessories, such as the
radio and air conditioner.
Voltmeter Gage
When your engine is not
running, but the ignition is
on, this gage shows
the battery’s state of
charge in DC volts.
When the engine is running, the gage shows the
condition of the charging system. The charging system
regulates voltage based on the state of the battery
for improved fuel economy and battery life. The gage
may transition from a higher to lower or a lower to higher
reading, this is normal. Readings between the low
and high warning zones indicate the normal operating
range. The gage may also read low during the fuel
economy mode, this is normal.
3-40

This light should come on briey when you turn the
ignition key to RUN. If it does not come on then, have it
xed so it will be ready to warn you if there is a problem.
{CAUTION:
Your brake system may not be working
properly if the brake system warning light is
on. Driving with the brake system warning light
on can lead to an accident. If the light is still
on after you have pulled off the road and
stopped carefully, have the vehicle towed for
service.
If the light comes on while you are driving, pull off the
road and stop carefully. You may notice that the pedal is
harder to push or may go closer to the oor. It may
take longer to stop. If the light is still on, have the vehicle
towed for service. SeeTowing Your Vehicle on
page 4-45.
Antilock Brake System (ABS)
Warning Light
For vehicles with the
Antilock Brake System
(ABS), this light comes on
briey when the engine
is started.
That is normal. If the light does not come on then, have it
xed so it will be ready to warn you if there is a problem.
If the ABS light stays on, turn the ignition off. If the light
comes on when you are driving, stop as soon as it is
safely possible and turn the ignition off. Then start the
engine again to reset the system. If the ABS light still
stays on, or comes on again while you are driving, your
vehicle needs service. If the regular brake system
warning light is not on, your vehicle still has brakes, but
not antilock brakes. If the regular brake system warning
light is also on, your vehicle does not have antilock
brakes and there is a problem with the regular brakes.
SeeBrake System Warning Light on page 3-41.
For vehicles with a Driver Information Center (DIC),
seeDIC Warnings and Messages on page 3-59for all
brake related DIC messages.
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