tow GMC SIERRA CLASSIC 2007 User Guide

Mirrors......................................................... 176
Manual Rearview Mirror............................. 176
Automatic Dimming Rearview Mirror with
OnStar
®, Compass and Temperature
Display................................................... 176
Automatic Dimming Rearview Mirror with
Compass and Temperature Display........ 180
Outside Manual Mirrors............................. 183
Outside Trailer-Tow Mirrors....................... 183
Outside West Coast-Type Mirrors.............. 185
Outside Power Mirrors............................... 185
Outside Power Foldaway Mirrors............... 186
Outside Automatic Dimming Mirror............. 187
Outside Curb View Assist Mirrors.............. 187
Outside Convex Mirror............................... 188
Outside Heated Mirrors............................. 188
OnStar
®System.......................................... 189Universal Home Remote System................ 191
Universal Home Remote System
(With Three Round LED)....................... 191
Universal Home Remote System
(With One Triangular LED)..................... 192
Universal Home Remote System
Operation (With Three Round LED)....... 193
Universal Home Remote System
Operation (With One Triangular LED)..... 198
Storage Areas............................................. 202
Glove Box................................................. 202
Cupholder(s).............................................. 202
Front Storage Area.................................... 202
Center Console Storage Area.................... 202
Tonneau Cover......................................... 203
Sunroof....................................................... 205
Section 2 Features and Controls
114

Programmable Automatic
Door Locks
Your vehicle may have an automatic lock/unlock
feature which enables you to program your
vehicle’s power door locks. You can program this
feature through the Driver Information Center
(DIC), or by the following method. SeeDIC Vehicle
Customization on page 282.
Programmable Locking Feature
Following are the two available programming
options:
Mode 1:All doors lock when the transmission is
shifted into gear. This is the mode that is
pre-programmed in the factory for your vehicle for
automatic transmission vehicles.Mode 2:All doors lock when the vehicle speed is
greater than 8 mph (13 km/h). This is the mode
that is pre-programmed in the factory for manual
transmission vehicles.
The following instructions tell you how to change
the automatic door lock mode (automatic
transmission only). Choose one of the two
programming options listed above before entering
the program mode. To enter the program mode,
do the following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.
2. Turn the key to RUN then back to LOCK
twice. Then, with the key in LOCK, release
the turn signal/multifunction lever. Once
you do this, the doors will lock and unlock, the
horn will chirp twice, and a 30-second timer
will begin. You are now ready to program
the automatic door lock feature.
123

Mode 4:No automatic door unlock.
The following instructions tell you how to
change the automatic door unlock mode
(automatic transmission only). Choose one of the
four programming options listed above before
entering the program mode. To enter the program
mode, do the following:
1. Begin with the ignition off. Then pull the turn
signal/multifunction lever toward you and hold
it there while you perform the next step.
2. Turn the key to RUN and LOCK twice. Then,
with the key in LOCK, release the turn
signal/multifunction lever. Once you do this,
the doors will lock and unlock, the horn
will chirp twice, and a 30-second timer will
begin. You are now ready to program
the automatic door unlock feature.3. Press the door unlock switch once. You will
hear one, two, three, or four chimes. The
number of chimes tells you which unlock mode
is currently selected. Continue to press the
door unlock switch until the number of chimes
that you hear matches the number of the
desired mode. If you take longer than
30 seconds, the locks will automatically lock
and unlock and the horn will chirp twice
to indicate that you have left the program
mode. If this occurs, you can repeat the
procedure beginning with Step 1 to re-enter
the programming mode.
You can exit the program mode any time by
turning the ignition to RUN. The doors will
automatically lock and unlock and the horn will
chirp twice to indicate that you are leaving
the program mode. If the lock/unlock switches are
not pressed while in the programming mode,
the current automatic settings will not be modied.
See your dealer for more information.
125

To open a rear access
door from the outside,
rst open the front door.
Then, use the handle
located on the front
edge of the rear access
door to open it.
You must fully close a rear access door before
you can close the front door.
To open a rear access
door from the inside, the
front door must be
opened rst. Then, use
the handle located on
the inside of the rear
access door to open it.Crew Cabs
If your vehicle is a crew cab, you can open your
doors from the inside or outside. Your vehicle may
also have a feature which prevents children
from opening the rear doors. SeeRear Door
Security Locks (Crew Cab) on page 126for more
information.
Tailgate
You can open the tailgate by lifting up on its
handle while pulling the tailgate toward you.
To shut the tailgate, rmly push it upward until it
latches.
After you put the tailgate back up, pull it back
towards you to be sure it latches securely.
127

Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:Your vehicle does not need an
elaborate break-in. But it will perform better in
the long run if you follow these guidelines:
Keep your speed at 55 mph (88 km/h)
or less for the rst 500 miles (805 km).
Do not drive at any one constant speed, fast
or slow, for the rst 500 miles (805 km). Do
not make full-throttle starts. Avoid
downshifting to brake, or slow, the vehicle.
Avoid making hard stops for the rst
200 miles (322 km) or so. During this time
your new brake linings are not yet broken
in. Hard stops with new linings can mean
premature wear and earlier replacement.
Follow this breaking-in guideline every time
you get new brake linings.
Do not tow a trailer during break-in. See
Towing a Trailer on page 429for the trailer
towing capabilities of your vehicle and more
information.
Following break-in, engine speed and load can
be gradually increased.
134

See “Range Selection Mode” later in this section.
PARK (P):This position locks your rear wheels. It
is the best position to use when you start your
engine because your vehicle cannot move easily. If
your vehicle has the Allison Transmission
®, with the
Power Take-Off (PTO), use PARK (P) when
starting. The Allison Transmission
®has a park pawl
that is designed to hold the weight of commercial
medium duty trucks. Therefore, the Allison
Transmission
®uses larger parts than other
automatic transmissions. These larger parts may
sometimes make a clunking noise when the
selector lever is moved from DRIVE (D) or
REVERSE (R) to PARK (P). This is normal and
there is no damage occurring during these shifts.
When parked on a hill, especially with a heavy load,you may notice an increase in the effort to shift out
of Park. See Torque Lock (Automatic Transmission)
underShifting Into Park (P) (Automatic
Transmission) on page 170for more information.
{CAUTION:
It is 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.
Do not leave your vehicle when the engine
is running unless you have to. 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, always set your parking brake
and move the shift lever to PARK (P).
SeeShifting Into Park (P) (Automatic
Transmission) on page 170. If you are
pulling a trailer, seeTowing a Trailer on
page 429.
Allison Transmission®
141

{CAUTION:
If you have four-wheel drive, your vehicle
will be free to roll — even if your shift
lever is in PARK (P) — if your transfer
case is in NEUTRAL. So, be sure the
transfer case is in a drive gear, two-wheel
high (2H) or four-wheel high (4H) or
four-wheel low (4L) — not in NEUTRAL.
SeeShifting Into Park (P) (Automatic
Transmission) on page 170.
REVERSE (R):Use this gear to back up. If your
vehicle has the Allison Transmission
®,theRonthe
shift display, may blink if the shift inhibitor is active.
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.
To rock your vehicle back and forth to get out of
snow, ice, or sand without damaging your
transmission, seeIf Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow on page 406.NEUTRAL (N):In this position, your engine does
not connect with the wheels. To restart when
you are already moving, use NEUTRAL (N) only.
Also, use NEUTRAL (N) when your vehicle is
being towed.
{CAUTION:
Shifting into a drive gear while your
engine is running at high speed is
dangerous. Unless your foot is rmly on
the brake pedal, your vehicle could move
very rapidly. You could lose control and
hit people or objects. Do not shift into a
drive gear while your engine is running at
high speed.
Notice:Shifting out of PARK (P) or
NEUTRAL (N) with the engine running at high
speed may damage the transmission. The
repairs would not be covered by your warranty.
Be sure the engine is not running at high
speed when shifting your vehicle.
142

DRIVE (D):This position is for normal driving. It
provides the best fuel economy for your vehicle. If
you need more power for passing, and you are:
Going less than about 35 mph (55 km/h), push
your accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push
the accelerator all the way down.
By doing this, the vehicle shifts down to the
next gear and has more power.
Downshifting the transmission in slippery road
conditions could result in skidding, see “Skidding”
underLoss of Control on page 371
DRIVE (D) can be used when towing a trailer,
carrying a heavy load, driving on steep hills, or for
off-road driving. You may want to shift the
transmission to THIRD (3) or, if necessary, a lower
gear selection if the transmission shifts too often.
If your vehicle has the Allison Transmission
®, it will
shift into rst range when DRIVE (D) is selected.
As vehicle speed increases, the transmission
will upshift automatically through each available
range up to SIXTH (6). As the vehicle slows,
the transmission will downshift automatically.The Allison Transmission
®uses a shift stabilization
feature that adjusts the transmission shifting to
the current driving conditions in order to reduce
rapid upshifts and downshifts. This shift
stabilization feature is designed to determine
before making an upshift if the engine will be able
to maintain vehicle speed by analyzing things
such as throttle position, vehicle load, and
hill grade. If the shift stabilization feature
determines that current vehicle speed cannot be
maintained, the transmission does not upshift
and instead holds the current gear. In some cases,
this may appear to be a delayed shift, however
the transmission is operating normally.
The Allison Transmission
®also uses adaptive shift
controls. Adaptive shift controls continually
compares key shift parameters to pre-programmed
ideal shift conditions. The Allison Transmission
®
constantly makes adjustments to improve vehicle
performance according to the way the vehicle is
being used, such as with a heavy load. During this
adaptive shift controls process, some shifts may
feel different as the transmission determines
optimum settings for a particular shift.
143

MANUAL MODE (M):This position, is available
on vehicles with the Allison 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
®) later in this section.
THIRD (3):This position is also used for normal
driving. However, it reduces vehicle speed
more than DRIVE (D) without using your 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 your 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.For an Allison Transmission
®, see Low Traction
Mode later in this section.
FIRST (1):For an automatic transmission, this
position reduces vehicle speed even more than
SECOND (2) without using your 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 will not shift into
rst gear until the vehicle is going slowly enough.
For an Allison Transmission
®, This position reduces
vehicle speed, without using your brakes. You can
use it for major/sever downgrades and off-road
driving where the vehicle would otherwise
accelerate due to steepness of grade. When you
shift to FIRST (1) it will provide the lowest gear
appropriate to your current road speed and will
continue 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.
144

Range Selection Mode
(Allison Transmission®)
If your truck has an Allison Transmission®your
vehicle has a Range Selection System.
To use this feature, do the following:
1. Move the shift lever to the MANUAL
MODE (M). When in the MANUAL MODE, the
transmission’s current gear range will be
the highest attainable range with all the lower
gears available.2. Press the plus/minus buttons to select the
desired range of gears for your current
driving conditions.
The Range Selection Mode allows you to
control the engine and vehicle speed while
driving down hill by allowing you to select
a desired gear.
The DIC shows the six available ranges with the
highest attainable range shown in brackets.
SeeDriver Information Center (DIC) on page 265
andDIC Operation and Displays on page 266
for more information.
While using the Range Selection mode, cruise
control and the Tow/Haul mode can be used.
Grade braking is not available while in the Range
Selection mode. SeeTow/Haul Mode on
page 147for more information.
145