2009 GMC SIERRA 1500 ECO mode

Notice:Do not let the LATCH attachments rub
against the vehicle’s safety belts. This may damage
these parts. If necessary, move buckled safety
belts to avoid rubbing the LATCH attachments.
Do not fold the empty rear seat with a safety belt
buckled. This could damage the safety belt or
the seat. Unbuckle and return the safety belt to its
stowed position, before folding the seat.
Regular Cab Models
1. If the child restraint manufacturer recommends that
the top tether be attached, attach and tighten the top
tether to the top tether anchor, if your vehicle has
one. Refer to the child restraint instructions and the
following steps:
1.1. Pull the passenger seatback forward by
pulling the recliner handle upward to access
the top tether anchor. SeeReclining
Seatbacks on page 1-10for additional
information.1.2. Find the top tether anchor.
1.3. Remove the cover to expose the anchor.
1.4. Route, attach, and tighten the top tether
according to your child restraint instructions
and the following instructions:
If the position you are using
has an adjustable headrest
or head restraint and you
are using a dual tether,
route the tether around the
headrest or head restraint.
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What Makes an Airbag Inate?
In a deployment event, the sensing system sends an
electrical signal triggering a release of gas from the
inator. Gas from the inator lls the airbag causing the
bag to break out of the cover and deploy. The inator, the
airbag, and related hardware are all part of the airbag
module.
Frontal airbag modules are located inside the steering
wheel and instrument panel. For vehicles with roof-rail
airbags, there are airbag modules in the ceiling of the
vehicle, near the side windows that have occupant
seating positions.
How Does an Airbag Restrain?
In moderate to severe frontal or near frontal collisions,
even belted occupants can contact the steering wheel
or the instrument panel. In moderate to severe side
collisions, even belted occupants can contact the inside
of the vehicle.Airbags supplement the protection provided by safety
belts. Frontal airbags distribute the force of the impact
more evenly over the occupant’s upper body, stopping
the occupant more gradually. Roof-rail airbags distribute
the force of the impact more evenly over the occupant’s
upper body.
Rollover capable roof-rail airbags are designed to help
contain the head and chest of occupants in the outboard
seating positions in the rst and second rows. The
rollover capable roof-rail airbags are designed to help
reduce the risk of full or partial ejection in rollover events,
although no system can prevent all such ejections.
But airbags would not help in many types of collisions,
primarily because the occupant’s motion is not
toward those airbags. SeeWhen Should an Airbag
Inflate? on page 1-77for more information.
Airbags should never be regarded as anything more
than a supplement to safety belts.
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Starting the Engine
If the vehicle has the DURAMAX®Diesel engine, see
the DURAMAX®Diesel manual for more information.
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
Notice:Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could damage
the transmission. Shift to P (Park) only when the
vehicle is stopped.
Move the shift lever to P (Park) or N (Neutral).
The engine will not start in any other position.
To restart the engine when the vehicle is already
moving, use N (Neutral) only.
Starting Procedure
1. With your foot off the accelerator pedal, turn the
ignition key to START. When the engine starts,
let go of the key. The idle speed will go down as
your engine gets warm. Do not race the engine
immediately after starting it. Operate the engine and
transmission gently to allow the oil to warm up
and lubricate all moving parts.The vehicle has a Computer-Controlled Cranking
System. This feature assists in starting the
engine and protects components. If the ignition key
is turned to the START position, and then
released when the engine begins cranking, the
engine will continue cranking for a few seconds or
until the vehicle starts. If the engine does not start
and the key is held in START for many seconds,
cranking will be stopped after 15 seconds to prevent
cranking motor damage. To prevent gear damage,
this system also prevents cranking if the engine is
already running. Engine cranking can be stopped by
turning the ignition switch to the ACC/ACCESSORY
or LOCK/OFF position.
Notice:Cranking the engine for long periods of
time, by returning the key to the START position
immediately after cranking has ended, can overheat
and damage the cranking motor, and drain the
battery. Wait at least 15 seconds between each try,
to let the cranking motor cool down.
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Active Fuel Management™
Vehicles with V8 engines 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 the 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.
If your vehicle has an Active Fuel Management™
indicator, seeDIC Operation and Displays (With DIC
Buttons) on page 3-53orDIC Operation and Displays
(Without DIC Buttons) on page 3-59for more information
on using this display.
Automatic Transmission Operation
Vehicles with an automatic transmission have an
electronic shift position indicator within the instrument
panel cluster. This display comes on when the ignition
key is turned to the ON/RUN position.
There are several different positions for the shift lever.
Hydra-Matic
®4-Speed
Automatic Transmission
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The vehicle has 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 is
able to maintain vehicle speed by analyzing things such
as vehicle speed, throttle position, and vehicle load.
If the shift stabilization feature determines that a current
vehicle speed cannot be maintained, the transmission
does not upshift and instead holds the current gear.
In some cases, this could appear to be a delayed shift,
however the transmission is operating normally.
The transmission uses adaptive shift controls.
Adaptive shift controls continually compares key shift
parameters to pre-programmed ideal shifts stored in the
transmissions computer. The transmission constantly
makes adjustments to improve vehicle performance
according to how the vehicle is being used, such as with
a heavy load or when temperature changes. During this
adaptive shift control process, shifting might feel different
as the transmission determines the best settings.
When temperatures are very cold, the Allison
Transmission
®and Hydra-Matic®6-Speed
transmission’s gear shifting could be delayed providing
more stable shifts until the engine warms up. Shifts
could be more noticeable with a cold transmission.
This difference in shifting is normal.M (Manual Mode):This position is available on
vehicles with the Allison Transmission
®or Hydra-Matic®
6-Speed transmission. It lets drivers select the range
of gears appropriate for current driving conditions.
If the vehicle has this feature, see Range Select Mode
(Allison Transmission
®or Hydra-Matic®6-Speed
transmission) later in this section.
3 (Third):This position is also used for normal driving.
It reduces vehicle speed more than D (Drive) without
using the brakes. You might choose 3 (Third) instead of
D (Drive) when driving on hilly, winding roads, when
towing a trailer, so there is less shifting between gears
and when going down a steep hill.
2 (Second):This position reduces vehicle speed even
more than 3 (Third) without using the brakes. You can
use 2 (Second) on hills. It can help control vehicle 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 2 (Second) 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 the vehicle
from a stop on slippery road surfaces.
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1 (First):For the Hydra-Matic®4-Speed transmission
this position reduces vehicle speed even more than
2 (Second) 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 1 (First) 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 the 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 1 (First) it provides the
lowest gear appropriate to current road speed and
continues to downshift as the vehicle slows, eventually
downshifting to 1 (First) 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 the vehicle warranty. If you
are stuck, do not spin the tires. When stopping on
a hill, use the brakes to hold the vehicle in place.
Range Selection Mode (Allison®or
Hydra-Matic®6-Speed Transmission)
The 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.
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To use this feature, do the following:
1. Move the shift lever to M (Manual Mode).
2. Press the plus/minus buttons, located on the
steering column shift lever, to select the desired
range of gears for current driving conditions.
When M (Manual Mode) is selected a number displays
next to the M, indicating the current gear.
This number is the highest gear that can be used.
However, the vehicle can automatically shift to lower
gears as it adjusts to driving conditions. This means
that all gears below that number are available.
When 5 (Fifth) is selected, 1 (First) through 5 (Fifth)
gears are automatically shifted by the vehicle, but
6 (Sixth) cannot be used until the plus/minus button
located on the steering column lever is used to change
to the gear.
Grade Braking is not available when Range Selection
Mode is active. SeeTow/Haul Mode on page 2-34.While using Range Selection Mode, 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 the vehicle 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®,orthe
Hydra-Matic®6-Speed Automatic Transmission,
it has a Low Traction Mode that can 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 Range Selection Mode.
This will limit torque to the wheels after it detects wheel
slip, preventing the tires from spinning.
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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 Four-Wheel High or Four-Wheel-Drive Low
you may experience reduced fuel economy.
Avoid driving in Four-Wheel Drive on clean, dry
pavement. It may cause your tires to wear faster,
make the transfer case harder to shift, and run
noisier.
If the transfer case shifter is in the N (Neutral)
position and you have difficulty reaching the
selected transfer case mode, with the engine
running, shift the transmission momentarily to drive
and then back to N (Neutral). This will realign the
gear teeth in the transfer case and allow you
to complete the shift.
Shifting from Two-Wheel-Drive High to
Four-Wheel-Drive High

Shifts between Two-Wheel-Drive High and
Four-Wheel-Drive High can be made at any
vehicle speed.
Shift the transfer case lever in one continuous
motion into either the Four-Wheel-Drive High
or Two-Wheel-Drive High position.
In extremely cold weather, it may be necessary
to slow or stop the vehicle to shift into
Four-Wheel-Drive High until the vehicle has
warmed up.
While in Four-Wheel-Drive High, the vehicle can be
driven at any posted legal speed limit.
Shifting In or Out of Four-Wheel-Drive Low
Notice:Shifting the transfer case into
Four-Wheel-Drive Low 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
Four-Wheel-Drive Low while the vehicle is moving
faster than 3 mph (5 km/h).
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