2006 CHEVROLET SILVERADO torque

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.
2-25

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.
2-29

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.
2-31

An indicator light near the lever shows you the transfer
case settings:
Notice:Driving on clean, dry pavement in
four-wheel drive 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 for extended periods of time.
4L (Four-Wheel Low):This setting also engages your
front axle and delivers extra torque. You may never
need 4L. It sends maximum power to all four wheels.
You might choose 4L if you are driving off-road in deep
sand, deep mud, deep snow, and while climbing or
descending steep hills. When operating in Four-Wheel
Low, the gear ratio provides additional torque when
compared to four-wheel high. The transmission
gear shift feel will be exaggerated.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P), or if you have a
manual transmission, even if you are in gear.
CAUTION: (Continued)
CAUTION: (Continued)
You or someone else could be seriously
injured. Be sure to set the parking brake
before placing the transfer case in NEUTRAL.
SeeParking Brake on page 2-49.
N (Neutral):Shift to this setting only when your vehicle
needs to be towed. SeeRecreational Vehicle Towing
on page 4-62orTowing Your Vehicle on page 4-61.
2H (Two-Wheel High):This setting is used for driving
in most street and highway situations. Your front
axle is not engaged in two-wheel drive. This setting also
provides the best fuel economy.
4H (Four-Wheel High):Use this setting when you
need extra traction, such as on snowy or icy roads or in
most off-road situations. This setting also engages
your front axle to help drive your vehicle. This is the best
setting to use when plowing snow.
You can shift from 2H to 4H or 4H high to 2H while the
vehicle is moving. Your front axle will engage faster
if you take your foot off of the accelerator for a couple
of seconds after you shift. In extremely cold weather, it
may be necessary to stop or slow the vehicle to
shift into four-wheel high.
2-38

When the vehicle detects a loss of traction, the system
will automatically engage four-wheel drive. Driving in
this mode results in slightly lower fuel economy
than Two-Wheel High.
2
m(Two-Wheel High):This setting is used for driving
in most street and highway situations. Your front axle
is not engaged in two-wheel drive. This setting also
provides the best fuel economy.
{CAUTION:
Shifting the transfer case to NEUTRAL
can cause your vehicle to roll even if the
transmission is in PARK (P). You or someone
else could be seriously injured. Be sure to set
the parking brake before placing the transfer
case in NEUTRAL. SeeParking Brake on
page 2-49.
N (NEUTRAL):Shift the vehicle’s transfer case to
N (NEUTRAL) only when towing your vehicle.
SeeRecreational Vehicle Towing on page 4-62or
Towing Your Vehicle on page 4-61for more information.4
m(Four-Wheel High):Use this setting when you
need extra traction, such a on snowy or icy roads or in
most off-road situations. This setting also engages
your front axle to help drive your vehicle. This is the best
setting to use when plowing snow.
4
n(Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. You may never
need Four-Wheel Low. It sends maximum power to all
four wheels. You might choose Four-Wheel Low if
you are driving off-road in deep sand, deep mud, deep
snow, and while climbing or descending steep hills.
When operating in Four-Wheel Low, the gear ratio
provides additional torque when compared to
four-wheel high. The transmission gear shift feel will
be exaggerated.
Indicator lights in the switches show which setting your
transfer case is in. The indicator lights will come on
briey when you turn on the ignition and one 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 the transfer case is being shifted. It will
stay on when the shift is complete. If for some reason
the transfer case cannot make a requested shift, it
will return to the last chosen setting.
If the SERVICE 4WD message stays on, you should
take your vehicle to your dealer for service. See
DIC Warnings and Messages on page 3-54for further
information.
2-41

4m(Four-Wheel High):This setting engages your
front axle to help drive your vehicle. Use four-wheel high
when you need extra traction, such as on snowy or
icy roads, or in most off-road situations.
4
n(Four-Wheel Low):This setting also engages
your front axle to give you extra traction. You may never
need Four-Wheel Low. It sends the maximum power
to all four wheels. You might choose Four-Wheel Low if
you were driving off-road in sand, mud or deep snow
and while climbing or descending steep hills. When
operating in Four-Wheel Low, the gear ratio provides
additional torque when compared to Four-Wheel
High. The transmission gear shift feel will be
exaggerated.
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 for service. An indicator light will ash
while shifting. Fast ashing means the conditions
were not met to make the desired shift, typically the
vehicle was going too fast, the automatic transmission
was not in neutral, or the clutch pedal was 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 cannot make a requested
shift, it will return to the last chosen setting.
Shifting from Two-Wheel High to
Four-Wheel High
Press and release the Four-Wheel High switch. This
can be done at any speed, and the front axle will lock
automatically with some delay.
Shifting from Four-Wheel High to
Two-Wheel High
Press and release the Two-Wheel High switch. This can
be done at any speed, and the front axle will unlock
automatically with some delay.
It is normal to hear and feel your vehicle’s transfer case
shift into Four-Wheel Low. If you shift with the vehicle
stopped, the indicator light may remain ashing 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 have the light stop ashing.
2-46

Leaving Your Vehicle With the Engine
Running (Automatic Transmission)
{CAUTION:
It can be dangerous to leave your vehicle with
the engine running. Your vehicle could move
suddenly if the shift lever is not fully in PARK
(P) with the parking brake rmly set.
If you have four-wheel drive and your transfer
case is in NEUTRAL, your vehicle will be free
to roll, even if your shift lever is in PARK (P).
So be sure the transfer case is in a drive
gear — not in NEUTRAL.
And, if you leave the vehicle with the engine
running, it could overheat and even catch re.
You or others could be injured. Do not leave
your vehicle with the engine running unless
you have to.If you have to leave your vehicle with the engine
running, be sure your vehicle is in PARK (P) and the
parking brake is rmly set before you leave it. After you
move the shift lever into PARK (P), hold the regular
brake pedal down. Then, see if you can move the shift
lever away from PARK (P) without rst pulling it
toward you. If you can, it means that the shift lever was
not fully locked into PARK (P).
Torque Lock (Automatic Transmission)
If you are parking on a hill and you do not shift your
transmission into PARK (P) properly, the weight of the
vehicle may put too much force on the parking pawl
in the transmission. You may nd it difficult to pull the
shift lever out of PARK (P). This is called “torque
lock.” To prevent torque lock, set the parking brake and
then shift into PARK (P) properly before you leave
the driver’s seat. To nd out how, see “Shifting
Into PARK (P)” listed earlier in this section.
When you are ready to drive, move the shift lever out of
PARK (P) before you release the parking brake.
If torque lock does occur, you may need to have another
vehicle push yours a little uphill to take some of the
pressure from the parking pawl in the transmission, so
you can pull the shift lever out of PARK (P).
2-51

Shifting Out of Park (P)
(Automatic Transmission)
Your vehicle has an automatic transmission shift lock
control system which locks the shift lever in PARK (P)
when the ignition is in the LOCK position. You have
to fully apply your regular brakes before you can shift
from PARK (P) when the ignition is in RUN. See
Automatic Transmission Operation on page 2-24and
“Torque Lock” underShifting Out of Park (P) (Automatic
Transmission) on page 2-52.
If your vehicle has an Allison Transmission
®, the
transmission is equipped with a park pawl designed to
hold the higher 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.If you cannot shift out of PARK (P), ease pressure on
the shift lever and push the shift lever all the way up into
PARK (P) as you maintain brake application. Then,
move the shift lever into the gear you want.
If you ever hold the brake pedal down but still can’t shift
out of PARK (P), try this:
1. Turn the key to ACCESSORY. There is no shift
interlock in this key position.
2. Apply and hold the brake until the end of Step 4.
3. Shift the transmission to NEUTRAL (N).
4. Start the vehicle and then shift to the gear
you want.
5. Have the system xed as soon as you can.
2-52