2007 GMC SIERRA automatic transmission

Keys............................................................ 109
Remote Keyless Entry (RKE) System........ 110
Remote Keyless Entry (RKE) System
Operation............................................... 111
Doors and Locks........................................ 118
Door Locks................................................ 118
Power Door Locks..................................... 119
Delayed Locking........................................ 119
Programmable Automatic Door Locks........ 119
Rear Door Security Locks......................... 120
Lockout Protection..................................... 120
Rear Doors............................................... 121
Tailgate..................................................... 122
Windows...................................................... 124
Manual Windows....................................... 124
Power Windows........................................ 125
Power Sliding Rear Window...................... 126
Sun Visors................................................ 127
Theft-Deterrent Systems............................. 127
Content Theft-Deterrent............................. 128
PASS-Key
®III+......................................... 129
PASS-Key®III+ Operation......................... 130Starting and Operating Your Vehicle......... 132
New Vehicle Break-In................................ 132
Ignition Positions....................................... 133
Retained Accessory Power (RAP)............. 134
Starting the Engine.................................... 134
Adjustable Throttle and Brake Pedal.......... 136
Engine Coolant Heater.............................. 136
Active Fuel Management™........................ 138
Automatic Transmission Operation............. 138
Tow/Haul Mode......................................... 144
Four-Wheel Drive...................................... 147
Parking Brake........................................... 162
Shifting Into Park (P)................................. 163
Shifting Out of Park (P)............................. 165
Parking Over Things That Burn................. 166
Engine Exhaust......................................... 167
Running the Engine While Parked............. 168
Mirrors......................................................... 169
Manual Rearview Mirror............................. 169
Automatic Dimming Rearview Mirror with
OnStar
®, Compass and Temperature
Display................................................... 169
Section 2 Features and Controls
107

Active Fuel Management™
Your vehicle’s V8 engine may have Active Fuel
Management™. This system allows the engine to
operate on either all or half of its cylinders,
depending on the driving conditions.
When less power is required, such as cruising at a
constant vehicle speed, the system will operate
in the half cylinder mode, allowing your vehicle to
achieve better fuel economy. When greater
power demands are required, such as accelerating
from a stop, passing, or merging onto a freeway,
the system will maintain full-cylinder operation.
Your vehicle has an Active Fuel Management™
indicator. For more information on using this
display seeDIC Operation and Displays (With DIC
Buttons) on page 268orDIC Operation and
Displays (Without DIC Buttons) on page 275.
Automatic Transmission Operation
If your vehicle is has an automatic transmission,
it has an electronic shift position indicator
within the instrument panel cluster. This display
comes on when the ignition key is turned to
the RUN position.There are several different positions for the
shift lever.
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 the engine
because your vehicle cannot move easily.
Hydra-Matic®4-Speed Automatic Transmission
Allison Transmission®or Hydra-Matic®6-Speed
Automatic Transmission
138

When parked on a hill, especially when the vehicle
has a heavy load, you might notice an increase in
the effort to shift out of Park. See Torque Lock
(Automatic Transmission) underShifting Into
Park (P) on page 163for 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). See
Shifting Into Park (P) on page 163.Ifyou
are pulling a trailer, seeTowing a Trailer
on page 445.
{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 Drive High or
Four-Wheel Drive High or Four-Wheel Drive
Low — not in NEUTRAL. SeeShifting Into
Park (P) on page 163.
REVERSE (R):Use this gear to back up.
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 422.
139

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 the 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.
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.
142

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.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.
143

Grade Braking is not available when the Range
Selection Mode is active. SeeTow/Haul Mode on
page 144.
While 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®,or
the 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.
Tow/Haul Mode
If your vehicle has an automatic transmission, it
has a tow/haul mode. If your vehicle has an Allison
or Hydra-Matic
®6-speed automatic transmission
see “Tow/Haul Mode (Allison or Hydra-Matic®
6-Speed Automatic Transmission®) following.
144

The 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 266for more
information.
Also see Tow Haul Mode underTowing a Trailer
on page 445for more information.Tow/Haul Mode (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
If your vehicle has an Allison or Hydra-Matic®
6-speed automatic transmission®, it has a tow/haul
mode. The 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.
145

Turn the tow/haul mode on and off by pressing the
button, located on the end of the shift lever.
When the tow/haul is on, a light on the instrument
panel cluster will come on.
SeeTow/Haul Mode Light on page 266for more
information.
Also see “Tow Haul Mode” underTowing a Trailer
on page 445for more information.
Grade Braking (Allison Transmission®
or Hydra-Matic®6-Speed Automatic
Transmission)
The Grade Braking shift modes can be activated
by pressing the button on the end of the shift
control lever. While in Range Selection Mode,
Grade Braking is deactivated allowing the driver to
select a desired range of gears.Grade Braking is only active while the Tow/Haul
Mode is selected and you are not in the Range
Selection Mode. See “Tow/Haul Mode listed
previously andAutomatic Transmission Operation
on page 138for more information on the Range
Selection Mode. Grade Braking assists in
maintaining desired vehicle speeds when driving
on downhill grades by automatically implementing
a shift schedule that utilizes the engine and
transmission to slow the vehicle. This reduces
wear on the braking system and increases control
of the vehicle. Grade Braking monitors vehicle
speed, acceleration, engine torque and brake
pedal usage. Using this information, it detects
when the truck is on a downhill grade and
the driver desires to slow the vehicle by pressing
the brake. See the diesel supplement for
information on Cruise Grade Braking.
Also seeTowing a Trailer on page 445for more
information.
146