2007 GMC SIERRA CLASSIC ECO mode

Cruise Grade Braking is available on the 6.6L
DURAMAX®diesel engine. Cruise Grade Braking
monitors a vehicle’s cruise state, engine torque,
acceleration, vehicle speed, and the cruise set
speed. Using this information, it detects when the
truck is accelerating on a downhill grade and will
automatically downshift to slow the vehicle if it
exceeds the cruise set speed by a certain amount.
SeeCruise Control on page 217for more
information.
The Tow/Haul mode and Grade Braking shift
modes can be activated by pressing the button on
the end of the shift control stalk. If your vehicle
has the DURAMAX
®diesel Engine or the
8.1L VORTEC™ gasoline engine, Grade Braking
is only available while the Tow/Haul Mode is
selected. While in the Range Selection Mode,
Grade Braking is deactivated allowing the driver to
select a desired range of gears.
SeeAutomatic Transmission Operation on
page 140for more information.
Also seeTowing a Trailer on page 429for more
information.
Manual Transmission Operation
Five-Speed
(VORTEC™ 6.0L V8 Engine)
Here is how to operate
your transmission.
FIRST (1) is intended only for heavy loads or
trailer towing and is not recommended for normal
driving.
During the rst 500 miles (805 km) of vehicle use,
start your vehicle moving in FIRST (1). This
allows clutch components to break-in properly.
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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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If the Four-Wheel Drive Low switch is pressed
when your vehicle is in gear and/or moving,
the Four-Wheel Drive Low indicator light will ash
for 30 seconds and the vehicle will not complete
the shift unless it is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).
After 30 seconds the transfer case will shift to
Four-Wheel Drive High mode.
Shifting Out of Four-Wheel Drive Low
To shift from Four-Wheel Drive Low to Four-Wheel
Drive High, AUTO 4WD, 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 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). Press and release the
Four-Wheel Drive High, AUTO 4WD, or
Two-Wheel Drive High switch. You must wait for
the Four-Wheel Drive High, AUTO 4WD, or
Two-Wheel Drive High indicator light to stop
ashing and stay on before shifting the
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 transfer case may make noise and the vehicle
may jerk when the transfer case is shifted
between Four-Wheel Drive Low and Four-Wheel
Drive High ranges or from NEUTRAL with the
engine running.
If the Four-Wheel Drive high, AUTO 4WD, or
Two-Wheel Drive High switch is pressed when
your vehicle is in gear and/or moving, the
Four-Wheel Drive High, AUTO 4WD, or
Two-Wheel Drive High indicator light will ash for
30 seconds but the vehicle will not complete
the shift unless it is moving less than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).
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Shifting Out of NEUTRAL
To shift out of NEUTRAL:
1. Set the parking brake and apply the regular
brake pedal.
2. Turn the ignition to RUN with the engine off.
3. Shift the transmission to NEUTRAL (N).
4. Press the button for the desired transfer case
shift position (Two-Wheel Drive High,
Four-Wheel Drive High, AUTO 4WD, or
Four-Wheel Drive Low).5. After the transfer case has shifted out of
NEUTRAL the red light will go out.
6. Release the parking brake prior to moving the
vehicle.
7. You may 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 mode
protects the transfer case from possible damage
and only allows the transfer case to respond
to one shift per 10 seconds. The transfer case may
stay in this mode for up to three minutes.
163

6. You may 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 mode protects the transfer case
from possible damage and only allows
the transfer case to respond to one shift per
10 seconds. The transfer case may stay in this
mode for up to three minutes.
7. After the transfer case has shifted out of
NEUTRAL the red light will go out.
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 will activate and the warning light will
ash when the parking brake is applied and
the vehicle is moving at least 3 mph (5 km/h) for
at least three seconds.To release the parking brake, hold the regular brake
pedal down. Pull the bottom edge of the lever,
located above the parking brake pedal, with the
parking brake symbol, to release the parking brake.
If the ignition is on when the parking brake is
released, the brake system warning light will go off.
Notice:Driving with the parking brake on can
overheat the brake system and cause premature
wear or damage to brake system parts. Verify
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 429.
169

To adjust between Fahrenheit and Celsius do the
following:
1. Press and hold the on/off button for
approximately four seconds until either a
ashing F or C appears.
2. Press the button again to change the display
to the desired unit of measurement. After
approximately four seconds of inactivity, the
new unit will be locked in and the
compass/temperature display will return.
If an abnormal temperature reading is displayed
for an extended period of time, please consult your
dealer. Under certain circumstances, a delay in
updating the temperature is normal.Automatic Dimming Mirror Operation
The automatic dimming mirror function is turned on
automatically each time the ignition is started.
To operate the automatic dimming mirror, do the
following:
1. Make sure the green indicator light, located to
the left of the on/off button, is lit. If it’s not, press
and hold the on/off button for approximately
six seconds until the green light comes on,
indicating that the mirror is in automatic
dimming mode.
2. Turn off the automatic dimming mirror function
by pressing and holding the on/off button for
approximately six seconds, until the green
indicator light turns off.
177

Compass Variance
The mirror is set in zone eight upon leaving the
factory. It will be necessary to adjust the compass
to compensate for compass variance if you live
outside of zone eight. Under certain
circumstances, as during a long distance
cross-country trip, it will be necessary to adjust for
compass variance. Compass variance is the
difference between earth’s magnetic north and true
geographic north. If not adjusted to account for
compass variance, your compass could give false
readings.
To adjust for compass variance do the following:
1. Find your current location and variance
zone number on the following zone map.
2. Press and hold the on/off button untilaZand
a zone number appear in the display. The
compass is now in zone mode.
3. Keep pressing the on/off button until the
desired zone number appears in the
display. Release the button. After
approximately four seconds of inactivity, the
new zone number will be locked in and
the compass/temperature display will return.
4. Calibrate the compass as described next.
178

Universal Home Remote System
Operation (With Three Round LED)
Your vehicle may have the Universal Home Remote
System. If there are three round Light Emitting
Diode (LED) above the Universal Home Remote
System buttons, follow the instructions below. If
there is one triangular LED above the Universal
Home Remote System buttons, follow the
instructions under Universal Home Remote System
Operation (with one triangular LED).
This system provides a way to replace up to three
remote control transmitters used to activate
devices such as garage door openers, security
systems, and home lighting.Do not use the this system with any garage door
opener that does not have the stop and reverse
feature. This includes any garage door opener
model manufactured before April 1, 1982.
Read the instructions completely before attempting
to program the transmitter. Because of the steps
involved, it may be helpful to have another
person available to assist you in programming the
transmitter.
Be sure to keep the original remote control
transmitter for use in other vehicles, as well as, for
future programming. You only need the original
remote control transmitter for xed code
programming. It is also recommended that upon
the sale or lease termination of the vehicle,
the programmed buttons should be erased for
security purposes. See “Erasing your Universal
Home Remote Buttons” later in this section.
Be sure that people and objects are clear of the
garage door or security device you are
programming. When programming a garage door,
it is advised to park outside of the garage.
193