2008 CHEVROLET SUBURBAN brake

FIRST (1):For the Hydra-Matic®4-Speed transmission
this position reduces vehicle speed even more than
SECOND (2) without using the brakes. You can use it
on very steep hills, or in deep snow or mud. If the
shift lever is put in FIRST (1) while the vehicle is moving
forward, the transmission does not shift into rst gear
until the vehicle is going slowly enough.
For an Allison Transmission
®or Hydra-Matic®6-Speed
transmission, this position reduces vehicle speed
without using your brakes. You can use it for
major/severe downgrades and off-road driving where
the vehicle would otherwise accelerate due to steepness
of grade. When you shift to FIRST (1) it provides the
lowest gear appropriate to your current road speed and
continues to downshift as the vehicle slows, eventually
downshifting to FIRST (1) gear.
Notice:Spinning the tires or holding the vehicle
in one place on a hill using only the accelerator
pedal may damage the transmission. The repair will
not be covered by your warranty. If you are stuck,
do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
Range Selection Mode (Allison®or
Hydra-Matic®6-Speed Transmission)
Your vehicle may have a Range Selection Mode.
The Range Selection Mode helps control the vehicle’s
transmission and vehicle speed while driving down hill
or towing a trailer by letting you select a desired range
of gears.
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To use this feature, do the following:
1. Move the shift lever to the MANUAL MODE (M).
2. Press the plus/minus buttons, located on the
steering column shift lever, to select the desired
range of gears for your current driving conditions.
When MANUAL MODE (M) is selected a number
displays next to the M, indicating the current gear.
This number is the highest gear that can be used.
However, your vehicle can automatically shift to lower
gears as it adjusts to driving conditions. This means that
all gears below that number are available. When
FIFTH (5) is selected, FIRST (1) through FIFTH (5)
gears are automatically shifted by the vehicle, but
SIXTH (6) cannot be used until the plus/minus button
located on the steering column lever is used to change
to the gear.
Grade Braking is not available when the Range
Selection Mode is active. SeeTow/Haul Mode on
page 2-36While using the Range Selection mode feature, cruise
control and the Tow/Haul mode can be used.
Notice:Spinning the tires or holding the vehicle
in one place on a hill using only the accelerator
pedal may damage the transmission. The repair will
not be covered by your warranty. If you are stuck,
do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
Low Traction Mode
If your vehicle has the Allison Transmission®,orthe
Hydra-Matic®6-Speed Automatic Transmission, it has a
Low Traction Mode that assist in vehicle acceleration
when road conditions are slippery, such as with ice
or snow. While the vehicle is at a stop, select the second
gear range using the Range Selection system. This
will limit torque to the wheels after it detects wheel slip,
preventing the tires from spinning.
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4m(Four-Wheel Drive High):Use the four-wheel high
position when you need extra traction, such as on
snowy or icy roads or in most off-road situations. This
setting also engages your front axle to help drive
your vehicle. This is the best setting to use when
plowing snow.
4
n(Four-Wheel Drive Low):This setting also
engages your front axle and delivers extra torque.
You may never need this setting. It sends maximum
power to all four wheels. You might choose Four-Wheel
Drive Low if you are driving off-road in deep sand,
deep mud, deep snow, and while climbing or descending
steep hills. StabiliTrak
®will not engage in this mode.
SeeStabiliTrak®System on page 4-6for more
information.
{CAUTION:
Shifting the transfer case to NEUTRAL can
cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-42.
NEUTRAL (N):Shift the vehicle’s transfer case to
NEUTRAL only when towing your vehicle. See
Recreational Vehicle Towing on page 4-45orTowing
Your Vehicle on page 4-45for more information.
If the SERVICE 4 WHEEL DRIVE message stays on,
you should take your vehicle to your dealer for service.
See “SERVICE 4 WHEEL DRIVE message” under
DIC Warnings and Messages on page 3-59.
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Shifting Out of Four-Wheel Drive Low
To shift from Four-Wheel Drive Low to Four-Wheel Drive
High, AUTO, or Two-Wheel Drive High, your vehicle
must be stopped or moving less than 3 mph (5 km/h)
with the transmission in NEUTRAL (N) and the ignition in
ON/RUN. The preferred method for shifting out of
Four-Wheel Drive Low is to have your vehicle moving
1 to 2 mph (1.6 to 3.2 km/h). Turn the knob to the
Four-Wheel Drive High, AUTO, or Two-Wheel Drive
High position. You must wait for the Four-Wheel Drive
High, AUTO, or Two-Wheel Drive High indicator
light to stop ashing and remain on before shifting your
transmission into gear.
Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has stopped
ashing could damage the transfer case. To help
avoid damaging your vehicle, always wait for the
Four-Wheel Drive Low indicator light to stop ashing
before shifting the transmission into gear.
The vehicle may have signicant engagement noise and
bump when shifting between Four-Wheel Drive Low
and Four-Wheel Drive High ranges or from NEUTRAL
while the engine is running.If the knob is turned to the Four-Wheel Drive High,
AUTO, or Two-Wheel Drive High switch position when
your vehicle is in gear and/or moving, the Four-Wheel
Drive High, AUTO or Two-Wheel Drive High indicator
light will ash for 30 seconds but will not complete
the shift unless your vehicle is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).
Shifting into NEUTRAL
To shift the transfer case to NEUTRAL do the following:
1. Make sure the vehicle is parked so that it
will not roll.
2. Set the parking brake and apply the regular brake
pedal. SeeParking Brake on page 2-42for more
information.
3. Start the vehicle or turn the ignition to ON/RUN.
4. Put the transmission in NEUTRAL (N).
5. Shift the transfer case to Two-Wheel Drive High.
6. Turn the transfer case dial clockwise to NEUTRAL till
it stops and hold it for 10 seconds. Then slowly
release the dial to the four low position. The
NEUTRAL light will come on when the transfer case
shift to NEUTRAL is complete.
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7. If the engine is running, verify that the transfer case
is in NEUTRAL (N) by shifting the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second.
8. Turn the ignition to ACC/ACCESSORY, which will
turn the engine off.
9. Place the transmission shift lever in PARK (P).
10. Release the parking brake prior to moving
the vehicle.
11. Turn the ignition to LOCK/OFF.
Shifting Out of NEUTRAL
To shift out of NEUTRAL do the following:
1. Set the parking brake and apply the regular
brake pedal.
2. Shift the transmission to NEUTRAL (N) and turn the
ignition to ON/RUN with the engine off.3. Turn the transfer case dial to the desired transfer
case shift position (Two-Wheel Drive High,
Four-Wheel Drive High, AUTO).
After the transfer case has shifted out of NEUTRAL
the NEUTRAL light will go out.
4. Release the parking brake prior to moving the
vehicle.
Notice:Shifting the transmission into gear before
the Four-Wheel Drive Low indicator light has
stopped ashing could damage the transfer case.
To help avoid damaging your vehicle, always
wait for the Four-Wheel Drive Low indicator light to
stop ashing before shifting the transmission
into gear.
5. Start the engine and shift the transmission to the
desired position.
Excessively shifting the transfer case into or out of the
different modes may cause the transfer case to enter the
shift protection mode. This will protect the transfer case
from possible damage and will only allow the transfer
case to respond to one shift per 10 seconds. The transfer
case may stay in this mode for up to three minutes.
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Parking Brake
To set the parking brake, hold the regular brake pedal
down with your right foot. Push down the parking
brake pedal with your left foot.
A chime sounds and the warning light ashes when the
parking brake is applied and the vehicle is moving at
least 5 mph (8 km/h).
To release the parking brake, hold the regular brake
pedal down. Then pull the bottom edge of the lever, with
the parking brake symbol and located above the
parking brake pedal.If the ignition is on when the parking brake is released,
the brake system warning light goes off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Make sure
that the parking brake is fully released and the brake
warning light is off before driving.
If you are towing a trailer and are parking on any hill,
seeTowing a Trailer on page 4-49.
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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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Leaving Your Vehicle With the Engine
Running
{CAUTION:
It can be dangerous to leave your vehicle
with the engine running. Your vehicle could
move suddenly if the shift lever is not fully in
PARK (P) with the parking brake rmly set.
If you have four-wheel drive and 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.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re.
You or others could be injured. Do not leave
your vehicle with the engine running unless
you have to.
If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and
the parking brake is rmly set before you leave it.After you move the shift lever into PARK (P), hold the
regular brake pedal down. Then, see if you can
move the shift lever away from PARK (P) without rst
pulling it toward you. If you can, it means that the
shift lever was not fully locked into PARK (P).
Torque Lock
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may nd it difficult to pull the
shift lever out of PARK (P). This is called torque lock.
To prevent torque lock, set the parking brake and
then shift into PARK (P) properly before you leave the
driver’s seat. To nd out how, seeShifting Into Park
on page 2-43.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission, then
you will be able to pull the shift lever out of PARK (P).
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