2007 GMC SIERRA CLASSIC clutch

Retained Accessory Power (RAP)
If the vehicle has Retained Accessory Power
(RAP), certain features will continue to operate for
up to 10 minutes after the ignition key is turned
to LOCK unless a door is opened.
Starting the Engine
Your vehicle has a Starter Motor Control. This
feature assists in starting the engine and protects
the electrical system. This feature may cause
the engine to crank even after the ignition key is
not in START.
Automatic Transmission
Move your shift lever to PARK (P) or
NEUTRAL (N). Your engine will not start in any
other position — that is a safety feature. To restart
when you are already moving, use NEUTRAL (N)
only. If you have a diesel engine refer to the
diesel supplement for the starting procedure.Notice:Do not try to shift to PARK (P) if your
vehicle is moving. If you do, you could
damage the transmission. Shift to PARK (P)
only when your vehicle is stopped.
Manual Transmission
The gear selector should be in NEUTRAL (N) and
the parking brake engaged. Hold the clutch
pedal to the oor and start the engine. Your
vehicle will not start if the clutch pedal is not all
the way down — that is a safety feature.
137

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.
149

FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal
as you press the accelerator pedal. Shift into
FIRST (1) only when the vehicle is below
5 mph (8 km/h).
Notice:If you try to shift down into FIRST (1) at
excessive vehicle speeds, clutch or engine
damage could occur. Do not shift into FIRST (1)
unless you are going less than 5 mph (8km/h).
SECOND (2):Press the clutch pedal and shift into
SECOND (2). Then, slowly let up on the clutch
pedal as you press the accelerator pedal.
You can shift into SECOND (2) when you are going
less than 20 mph (32 km/h). If you have come to a
complete stop and it is hard to shift into
SECOND (2), put the shift lever into NEUTRAL and
let up on the clutch. Press the clutch pedal back
down. Then shift into SECOND (2).
Notice:If you try to shift down into
SECOND (2) at excessive vehicle speeds,
clutch or engine damage could occur. Do not
shift into SECOND (2) unless you are going
less than 20 mph (32km/h).THIRD (3):Press the clutch pedal and shift into
THIRD (3). Then, slowly let up on the clutch pedal
as you press the accelerator pedal.
FOURTH (4) and FIFTH (5):Shift into the higher
forward gears the same way you do for
THIRD (3). Slowly let up on the clutch pedal as
you press the accelerator pedal.
To stop, let up on the accelerator pedal and press
the brake pedal. Just before the vehicle stops,
press the clutch pedal and the brake pedal,
and shift to NEUTRAL.
NEUTRAL:Use this position when you start or
idle your engine.
REVERSE (R):To back up, rst press down the
clutch pedal. Wait for the vehicle to stop moving
and then, shift into REVERSE (R). Let up on
the clutch pedal slowly while pressing the
accelerator pedal.
Notice:Shifting to REVERSE (R) while your
vehicle is moving forward could damage the
transmission. The repairs would not be covered
by your warranty. Shift to REVERSE (R) only
after your vehicle is stopped.
150

Also, use REVERSE (R), along with the parking
brake, when turning off your engine and parking
your vehicle.
Five-Speed (VORTEC™ 4.3L V6 and
4.8L V8 Engines)
Here is how to operate your transmission:
FIRST (1):Press the clutch pedal and shift into
FIRST (1). Then, slowly let up on the clutch pedal
as you press the accelerator pedal.
You can shift into FIRST (1) when you are going
less than 20 mph (32 km/h). If you have come to a
complete stop and it is hard to shift into FIRST (1),
put the shift lever into NEUTRAL and let up on
the clutch. Press the clutch pedal back down. Then
shift into FIRST (1).
Notice:If you try to shift down into FIRST (1)
at excessive vehicle speeds, clutch or
engine damage could occur. Do not shift into
FIRST (1) unless you are going less than
20 mph (32km/h).
SECOND (2):Press the clutch pedal as you let
up on the accelerator pedal and shift into
SECOND (2). Then, slowly let up on the clutch
pedal as you press the accelerator pedal.THIRD (3), FOURTH (4) and FIFTH (5):Shift into
THIRD (3), FOURTH (4) and FIFTH (5) the same
way you do for SECOND (2). Slowly let up on the
clutch pedal as you press the accelerator pedal.
To stop, let up on the accelerator pedal and press
the brake pedal. Just before the vehicle stops,
press the clutch pedal and the brake pedal, and
shift to NEUTRAL.
NEUTRAL:Use this position when you start or
idle your engine.
REVERSE (R):To back up, rst press down the
clutch pedal. Wait for the vehicle to stop moving
and then, shift into REVERSE (R). Let up on
the clutch pedal slowly while pressing the
accelerator pedal.
Notice:Shifting to REVERSE (R) while your
vehicle is moving forward could damage
the transmission. The repairs would not be
covered by your warranty. Shift to
REVERSE (R) only after your vehicle is
stopped.
Also, use REVERSE (R), along with the parking
brake, when turning off your engine and parking
your vehicle.
151

Shifting In or Out of 4L (Four-Wheel
Drive Low)
Notice:Shifting the transfer case into 4L
while moving at speeds faster than 3 mph
(5 km/h) may cause premature wear to
the transfer case, and may cause the gears to
grind. To avoid causing premature wear,
and grinding the gears, do not shift the transfer
case into 4L while the vehicle is moving
faster than 3 mph (5 km/h).
Shifts into 4L can be made with the vehicle at a
stop, or while slowly rolling about 1 to 3 mph
(2 to 5 km/h).
Shift the automatic transmission into
NEUTRAL (N), or with a manual transmission,
press the clutch pedal, or shift into NEUTRAL.
Shift the transfer case shift lever in one
continuous motion into the 4L position.
When in 4L do not drive faster than 45 mph.
This will reduce wear and extend the life of
the transfer case.
Shifting In or Out of NEUTRAL
1. With the vehicle running and the engine at an
idle set the parking brake and apply the
regular brake.
2. Place the transmission into NEUTRAL (N).
Shift the transfer case in one continuous motion
into or out of the NEUTRAL position.
Automatic Transfer Case
The transfer case
buttons are located to
the left of the instrument
panel cluster.
Use these switches to shift into and out of
four-wheel drive.
157

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.
158

Electronic Transfer Case
If your four-wheel-drive
vehicle has the
electronic transfer case,
the transfer case
switches are located to
the left of the
instrument panel cluster.
Recommended Transfer Case Settings
Driving ConditionsTransfer Case Settings
2m4m4nN
Normal YES
Severe YES
Extreme YES
Vehicle in Tow* YES
*SeeRecreational Vehicle Towing on page 424or
Towing Your Vehicle on page 423for further
information.
Use these switches to shift into and out of
four-wheel drive. You can choose among
three driving settings:
Indicator lights in the switches show you which
setting you are in. 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 in 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.
2
m(Two-Wheel Drive High):This setting is for
driving in most street and highway situations.
The front axle is not engaged in two-wheel drive.
164

Shifting from Two-Wheel Drive High or
Four-Wheel Drive High to Four-Wheel
Drive Low
To shift from Two-Wheel Drive High or Four-Wheel
Drive High to Four-Wheel Drive Low, the vehicle
must be stopped or moving less than 3 mph
(5 km/h) with the transmission in NEUTRAL (N) for
an automatic transmission, or the clutch pedal
pressed for a manual transmission. The preferred
method for shifting into Four-Wheel Drive Low
is to have your vehicle moving 3 mph (5 km/h).
Press and release the Four-Wheel Drive Low
switch. You must wait for the Four-Wheel Drive
Low indicator light to stop ashing and stay
on before shifting the transmission into gear or
releasing the clutch pedal.
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.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 not complete the shift
unless your vehicle is moving slower than 3 mph
(5 km/h) and the transmission is in NEUTRAL (N).
The transfer case will shift to Four-Wheel Drive
High while waiting to complete the shift.
It is normal to hear and feel your vehicle’s transfer
case shift into Four-Wheel Drive Low. If you shift
with the vehicle stopped, the indicator light may
continue to ash slowly. It may be necessary to shift
the transmission momentarily into REVERSE (R)
and DRIVE (D), for an automatic transmission, or
REVERSE (R) and FIRST (1) for a manual
transmission to make the light stop ashing.
166