2006 CHEVROLET SILVERADO engine

3. Plug it into a normal, grounded 110-volt AC outlet.
{CAUTION:
Plugging the cord into an ungrounded outlet
could cause an electrical shock. Also, the
wrong kind of extension cord could overheat
and cause a re. You could be seriously
injured. Plug the cord into a properly grounded
three-prong 110-volt AC outlet. If the cord will
not reach, use a heavy-duty three-prong
extension cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and
store the cord as it was before to keep it away
from moving engine parts. If you do not, it could be
damaged.
How long should you keep the coolant heater plugged
in? The answer depends on the outside temperature, the
kind of oil you have, and some other things. Instead
of trying to list everything here, we ask that you contact
your dealer in the area where you will be parking
your vehicle. The dealer can give you the best advice
for that particular area.
Automatic Transmission Operation
If your vehicle is has an automatic transmission, it
features an electronic shift position indicator within the
instrument panel cluster. This display must be powered
anytime the shift lever is moved out of PARK (P).
SeeFuses and Circuit Breakers on page 5-126.
There are several different positions for your shift lever.
See “Range Selection Mode” later in this section.Automatic Transmission
Allison Transmission®
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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
Takeoff (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 clunk 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 when loaded, 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 2-50for
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 2-50. If you are pulling
a trailer, seeTowing a Trailer on page 4-67.
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{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 2-50.
REVERSE (R):Use this gear to back up. If your vehicle
has the Allison Transmission
®, the R on the 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 4-46.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.
DRIVE (D):This position is for normal driving. 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.
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By doing this, the vehicle shifts down to the next gear
and has more power.
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.
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 offers more power and lower fuel economy
than DRIVE (D).
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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 upshift or downshift
selecting the desired range of gears for your current
driving conditions.
The Range Selection Mode allows you to control the
vehicle’s 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 3-51andDIC
Operation and Displays on page 3-52for more
information.
While using the Range Selection mode feature, cruise
control and the Tow/Haul mode can be used.
Low Traction Mode
(Allison Transmission®)
If your vehicle has the DURAMAX®diesel engine and
the Allison Transmission®, it is equipped with a Low
Traction Mode that assists in vehicle acceleration when
road conditions are slippery, such as ice or snow.While at a stop, selecting the second gear range using
the Range Selection system, will allow the Allison
Transmission
®to limit torque to the wheels after it
detects wheel slip, preventing the tires from spinning.
Notice:Spinning the tires or holding the vehicle in
one place on a hill using only the accelerator
pedal may damage the transmission. If you are
stuck, do not spin the tires. When stopping on a hill,
use the brakes to hold the vehicle in place.
Cold Weather Operation
(Allison Transmission®)
On cold days, approximately 32°F (0°C) or colder, your
automatic transmission is designed to shift differently.
The transmission uses a warm-up mode shift schedule
until the engine reaches normal operating temperature.
While the transmission is in warm-up mode it is
normal for transmission upshifts to be delayed or held
longer. This feature improves heater performance
by giving quicker vehicle warm-ups.
When temperatures are below−13°F (−25°C), the
transmission will prevent certain operations to protect
against damage. When active the DIC will display
the message “Trans in Warm-up”.
SeeDIC Warnings and Messages on page 3-54for
more information.
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The selector button is located on the end of the shift
lever. Turn the Turn 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 3-49for more
information.
Also see “Tow Haul Mode” underTowing a Trailer on
page 4-67for more information.
Grade Braking and Cruise Grade
Braking (Allison Transmission®)
Grade Braking and Cruise Grade Braking assists when
driving on a downhill grade. It maintains the vehicle’s
speed by automatically implementing a shift schedule
that uses the engine and the transmission to slow
the vehicle. This reduces wear on the brakes system
and increases control of the vehicle. The system
constantly monitors the vehicle’s speed, acceleration,
engine torque, and brake pedal usage. It detects
when the truck is on a downhill grade and the driver’s
desire to slow down by pressing the brake.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 3-10for more information.
The Tow/Haul mode and Grade Braking shift modes
can be activated by pressing the button on the front
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 gear.
SeeAutomatic Transmission Operation on page 2-24for
more information.
Also seeTowing a Trailer on page 4-67for more
information.
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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.
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). If you
try to shift down into FIRST (1) at excessive vehicle
speeds, the shift lever will not move into FIRST (1)
until vehicle speed is reduced.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). If you try to downshift into SECOND (2) at
excessive vehicle speeds, the shift lever will not move
into the SECOND (2) position until the vehicle speed
is reduced.
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.
2-32

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.
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).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.
2-33