light GMC SIERRA CLASSIC 2007 Owner's Manual

Swing-Out Windows
Your vehicle may have
swing-out windows. To
open a rear swing-out
window, ip the
latch open and swing
the glass out.
The latch will catch when the window is fully open
and it will also hold it in the open position.
Sliding Rear Window
If your vehicle has this feature, squeeze the latch
in the center of the window and slide the glass
to open it.
When you close the window, be sure the latch is
engaged.
The sliding rear window does not have rear
defogger.
Sun Visors
Pull the sun visor down to block glare. Swing the
sun visor to the side to cover the side window.
The passenger’s side sun visor may have a vanity
mirror.
Theft-Deterrent Systems
Vehicle theft is big business, especially in some
cities. Although your vehicle has a number of
theft-deterrent features, we know that nothing we
put on it can make it impossible to steal.
Content Theft-Deterrent
Your vehicle may have a content theft-deterrent
alarm system.
The security light,
located on the
instrument panel cluster,
will ash as you open
the door, while the
ignition is off, to indicate
the system is being
activated.
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This message reminds you to activate the
theft-deterrent system. Here is how to do it:
1. Open the door.
2. Lock the door with the Remote Keyless Entry
(RKE) transmitter. The security light should
come on and ash. The door does not need to
be open.
If the delayed locking feature is active, the
alarm will not be activated until all doors are
closed and the security light goes off.
3. Close all doors. The security light will stop
ashing and go off after approximately
30 seconds. The content theft deterrent alarm
is not armed until the security light goes off.
If a door is opened without using the RKE
transmitter, the alarm will go off. Your vehicle’s
headlamps will ash and the horn will sound
for about two minutes, then will turn off to save
the battery power.The theft-deterrent system will not activate if you
lock the doors with a key, the manual door lock, or
the power door lock switch. It activates only if you
use the RKE transmitter. You should also
remember that you can start your vehicle with the
correct ignition key if the alarm has been set off.
Here is how to avoid setting off the alarm by
accident:
If you do not want to activate the
theft-deterrent system, the vehicle should be
locked with the door key after the doors
are closed.
Always unlock a door with the remote keyless
entry transmitter. Unlocking a door any other
way will set off the alarm if the system
has been armed.
If you set off the alarm by accident, turn off the
alarm by pressing unlock on the remote keyless
entry transmitter or by placing the key in the
ignition and turning it to START.
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Testing the Alarm
The alarm can be tested by following these steps:
1. From inside the vehicle, lower the driver’s
window and open the driver’s door.
2. Activate the system by locking the doors with
the RKE transmitter.
3. Get out of the vehicle, close the door and wait
for the security light to go out.
4. Then reach in through the window, unlock the
door with the manual door lock and open the
door. This should set off the alarm.
If the alarm does not sound when it should, but
the vehicle’s headlamps ash, check to see if the
horn works. The horn fuse may be blown. To
replace the fuse, seeFuses and Circuit Breakers
on page 600.
If the alarm does not sound or the vehicle’s
headlamps do not ash, see your dealer for
service.
Passlock®
Your vehicle has the Passlock®theft-deterrent
system.
Passlock
®is a passive theft-deterrent system.
Passlock®enables fuel if the ignition lock cylinder
is turned with a valid key. If a correct key is
not used or the ignition lock cylinder is tampered
with, fuel is disabled.
If the engine stalls and the security light ashes,
wait until the light stops ashing before trying
to restart the engine. Remember to release the key
from START as soon as the engine starts.
If the engine is running and the security light
comes on, you will be able to restart the engine if
you turn the engine off. However, your
Passlock
®system is not working properly and
must be serviced by your dealer. Your vehicle is
not protected by Passlock
®at this time. You
may also want to check the fuse. SeeFuses and
Circuit Breakers on page 600. See your dealer
for service.
In an emergency, call the GM Roadside
Assistance Center. SeeRoadside Assistance
Program on page 644.
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Tow/Haul Mode
If your vehicle has an automatic transmission, it
may have a Tow/Haul mode. If your vehicle has an
Allison Transmission
®see “Tow/Haul Mode
(Allison Transmission®) following. Tow/Haul mode
adjusts the transmission shift pattern to reduce
shift cycling, providing increased performance,
vehicle control, and transmission cooling
when towing or hauling heavy loads.The selector button is located on the end of the
shift lever. Turn the Tow/Haul on and off by
pressing the button. When the Tow/Haul is on, a
light on the instrument panel cluster will come on.
SeeTow/Haul Mode Light on page 264for
more information.
If your vehicle has the Performance
Package-Enhanced Towing, activating the manual
selectable ride will adjust the shock absorber
characteristics to enhance the ride and handling of
the vehicle for towing or hauling heavy loads.
Also see Tow Haul Mode underTowing a Trailer
on page 429for more information.
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Tow/Haul Mode (Allison
Transmission®)
If your vehicle has an Allison Transmission®,it
may have a Tow/Haul mode. Tow/Haul mode
adjusts the transmission shift pattern to reduce
shift cycling, providing increased performance,
vehicle control, and transmission cooling
when towing or hauling heavy loads.The selector button is located on the end of the shift
lever. Turn the Tow/Haul on and off by pressing the
button. When the Tow/Haul is on, a light on the
instrument panel cluster will come on.
SeeTow/Haul Mode Light on page 264for more
information.
Also see “Tow Haul Mode” underTowing a Trailer
on page 429for more information.
Grade Braking and Cruise Grade
Braking (Allison Transmission®)
Grade Braking and Cruise Grade Braking assists
when driving on a downhill grade. It maintains
the vehicle’s speed by automatically using a shift
schedule that uses the engine and the
transmission to slow the vehicle. This reduces
wear on the brakes system and increases control
of the vehicle. The system constantly monitors
the vehicle’s speed, acceleration, engine torque,
and brake pedal usage. It detects when the
truck is on a downhill grade and the driver’s desire
to slow down by pressing the brake.
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Shift Speeds
{CAUTION:
If you skip a gear when you downshift,
you could lose control of your vehicle.
You could injure yourself or others. Do
not shift down more than one gear at a
time when you downshift.
Do not allow the engine Revolutions Per Minute
(RPM) to overspeed and enter the tachometer red
lines. Engine overspeed occurs when downshifting,
or descending a grade, at too high a vehicle
speed. When going down steep grades, always
select a gear at least one position lower than you
would use on climbing a grade. This will allow
the vehicle’s engine to provide some braking and
help to slow the vehicle as it goes down the
grade. Monitor your vehicle speed, acceleration
and engine RPM while applying the brakes as you
go down the grade to ensure you have complete
control over the vehicle.If your engine speed drops below 600 rpm, or if
the engine is not running smoothly, you should
downshift to the next lower gear. When operating
on slippery surfaces, downshift at lower than
normal vehicle speeds to prevent the tires from
slipping.
In vehicles that have a bench seat, move the
tallest beverage containers to the right cupholder
to provide additional clearance for the shift
lever.
For vehicles that have a center console, the front
cup holder pulls out and turns 180° to provide
additional clearance between tall beverage
containers and the shift lever.
Up-Shift Light
If your vehicle has a
manual transmission,
you may have a shift
light. This light will show
you when to shift to the
next higher gear for best
fuel economy.
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When this light comes on, you can shift to the next
higher gear if weather, road and traffic conditions
allow. For the best fuel economy, accelerate slowly
and shift when the light comes on.
While you accelerate, it is normal for the light to
go on and off if you quickly change the position of
the accelerator.
If your vehicle has four-wheel drive and has a
manual transmission, disregard the shift light when
the transfer case is in Four-Wheel Low.
Ignore the shift light when you downshift.
Four-Wheel Drive
If your vehicle has four-wheel drive, you can send
your engine’s driving power to all four wheels
for extra traction. To get the most satisfaction out
of four-wheel drive, you must be familiar with
its operation. Read the part that follows before
using four-wheel drive. See the appropriate text for
the transfer case in your vehicle.
While driving on clean dry pavement and during
tight turns, you may experience a vibration in
the steering system.
Front Axle Locking Feature
The front axle locks and unlocks automatically
when you shift the transfer case. Some delay for
the axle to lock or unlock is normal.
Manual Transfer Case
The transfer case shift lever is located on the oor
to the right of the driver. Use this lever to shift
into and out of four-wheel drive.
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A 4WD indicator light
comes on when you
shift into four-wheel
drive and the front axle
engages. See
Four-Wheel-Drive Light
on page 263.
Some delay between shifting and when the
indicator light comes on is normal.
Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2H 4H 4L N
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeRecreational Vehicle Towing on page 424or
Towing Your Vehicle on page 423for further
information.
An indicator light near the lever shows you the
transfer case settings:
Notice:Driving on clean, dry pavement in
four-wheel drive for an extended period of time
may cause premature wear on your vehicle’s
powertrain. Do not drive on clean, dry
pavement in four-wheel drive for extended
periods of time.
4L (Four-Wheel Low):This setting also engages
the front axle and delivers extra torque. You
may never need 4L. It sends maximum power to
all four wheels. You might choose 4L if you
are driving off-road in deep sand, deep mud, deep
snow, and while climbing or descending steep
hills. When operating in 4L, the gear ratio provides
additional torque when compared to 4H. The
transmission gear shift feel will be exaggerated.
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When Using the Manual Transfer Case

Shifting should be made using quick motions.
Shifting slowly may make it more difficult to
shift.
You may notice that it is harder to shift when
the vehicle is cold. After the vehicle warms
up the shifting will return to normal.
While in 4H or 4L you may experience
reduced fuel economy.
Avoid driving in four-wheel drive on clean, dry
pavement. Doing this may cause the tires to
wear faster, and make your transfer case
harder to shift, and run noisier.
Shifting from 2H (Two-Wheel Drive High)
to 4H (Four-Wheel Drive High)

Shifts between 2H and 4H can be made at
any vehicle speed.
It is easiest to shift the transfer case when
maintaining a constant speed or during a slight
acceleration. If possible, avoid shifting while
slowing down, as it will make it harder to shift.
Shift the transfer case lever in one continuous
motion into either the 4H or 2H position.
In extremely cold weather, it may be necessary
to slow or stop the vehicle to shift into 4H until
your vehicle has warmed up.
While in 4H, your vehicle can be driven at any
posted legal speed limit.
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Recommended Transfer Case Settings
Driving
ConditionsTransfer Case Settings
2
mAUTO
4WD4m4nN
Normal YES
Variable YES
Severe YES
Extreme YES
Vehicle in
Tow*YES
*SeeRecreational Vehicle Towing on page 424for
further information.
You can choose among ve driving settings:
Notice:Driving on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive
Low for an extended period of time may cause
premature wear on your vehicle’s powertrain.
Do not drive on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive
Low for extended periods of time.Indicator lights in the switches show the current
setting. The indicator lights will come on briey
when you turn on the ignition and the last chosen
setting will stay on. If the lights do not come
on, you should take your vehicle to your dealer for
service. An indicator light will ash while shifting.
Fast ashing means the conditions are not
being met to make the desired shift, typically the
vehicle is going too fast, the automatic
transmission is not in NEUTRAL, or the clutch
pedal is not fully pressed. Slow ashing means the
shift is in progress. It will stay on when the shift
is completed. If for some reason the transfer case
cannot make a requested shift, it will return to
the last chosen setting.
AUTO 4WD (Automatic Four-Wheel Drive):This
setting is ideal for use when road surface
traction conditions are variable. When driving your
vehicle in AUTO 4WD, the front axle is engaged,
but the vehicle’s power is primarily sent to the rear
wheels. When the vehicle’s software determines
a need for more traction, the system will
transfer more power to the front wheels. Driving in
this mode results in slightly lower fuel economy
than Two-Wheel Drive High.
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