2007 CHEVROLET SILVERADO engine

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
the 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 447for the
trailer towing capabilities of your vehicle
and more information.
Following break-in, engine speed and load can
be gradually increased.
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Ignition Positions
Use the key to turn the ignition switch to
four different positions.
A (LOCK):This position locks the ignition and
transmission. It is a theft-deterrent feature. You will
only be able to remove the key when the ignition is
turned to LOCK.
Notice:Using a tool to force the key from the
ignition switch could cause damage or break
the key. Use the correct key and turn the key
only with your hand. Make sure the key is all the
way in. If it is, turn the steering wheel left and
right while you turn the key hard. If none of this
works, then your vehicle needs service.B (ACCESSORY):This position lets you use
things like the radio and the windshield wipers
when the engine is off.
Lengthy operation of features such as the radio in
the ACCESSORY ignition position and the
RUN position may drain the battery and prevent
your vehicle from starting. Do not operate
your vehicle in the ACCESSORY ignition position
for a long period of time.
C (RUN):This is the position for driving. It is the
position the switch returns to after the engine
starts, and you release the key.
The battery could be drained if you leave the key
in the ACCESSORY or RUN position with the
engine off. You may not be able to start your
vehicle if the battery is allowed to drain for
an extended period of time.
D (START):This position starts the engine.
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Key In the Ignition
Never leave your vehicle with the keys inside, as it
is an easy target for joy riders or thieves. If you
leave the key in the ignition and park your vehicle, a
chime will sound, when you open the driver’s door.
Always remember to remove your key from the
ignition and take it with you. This will lock your
ignition and transmission. Also, always remember
to lock the doors.
The battery could be drained if you leave the key in
the ignition while your vehicle is parked. You may
not be able to start your vehicle after it has been
parked for an extended period of time.
Retained Accessory Power (RAP)
Your vehicle has a Retained Accessory Power
(RAP) feature which will allow certain features on
your vehicle to continue to work up to 10 minutes
after the ignition key is turned to LOCK.
The radio, power windows, and if the vehicle has a
sunroof and the OnStar
®System, will work when
the ignition key is in RUN or ACCESSORY. Once
the key is turned from RUN to LOCK, the windows
and sunroof will continue to work until a door is
opened. The radio will continue to work for up to
10 minutes or until the driver’s door is opened.
Starting the Engine
If your vehicle has the DURAMAX®Diesel engine,
see the DURAMAX®Diesel manual for more
information.
To place the transmission in the proper gear:
Move your shift lever to PARK (P) or
NEUTRAL (N). Your engine will not start in
any other position -- this is a safety feature. To
restart when you are already moving, use
NEUTRAL (N) 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.
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Your 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
ACCESSORY or LOCK 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 allow
the cranking motor to cool down.2. If the engine does not start after 5-10 seconds,
especially in very cold weather (below 0°F or
−18°C), it could be ooded with too much
gasoline. Try pushing the accelerator pedal all
the way to the oor and holding it there as
you hold the key in START for up to a
maximum of 15 seconds. Wait at least
15 seconds between each try, to allow the
cranking motor to cool down. When the engine
starts, let go of the key and accelerator. If
the vehicle starts briey but then stops again,
do the same thing. This clears the extra
gasoline from the engine. Do not race the
engine immediately after starting it. Operate
the engine and transmission gently until the oil
warms up and lubricates all moving parts.
Notice:Your engine is designed to work with
the electronics in your vehicle. If you add
electrical parts or accessories, you could
change the way the engine operates. Before
adding electrical equipment, check with your
dealer. If you do not, your engine might not
perform properly. Any resulting damage would
not be covered by your vehicle’s warranty.
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Adjustable Throttle and Brake Pedal
If your vehicle has this feature, you can change
the position of the throttle and brake pedals.
This feature is designed for shorter drivers, since
the pedals cannot move farther away from the
standard position, but can move toward the driver
for better pedal reach.
The switch used to
adjust the pedals is
located on the
instrument panel below
the climate control
system.
Press the arrow at the bottom of the switch to
move the pedals closer to your body. Press
the arrow at the top of the switch to move the
pedals away from your body.Before you start driving, fully press the brake
pedal to conrm the adjustment is right for you.
While driving, make only small adjustments.
No adjustment to the pedals can be made when
the vehicle is in REVERSE (R) or while using
the cruise control.
Your vehicle may have a memory function which
allows pedal settings to be saved and recalled.
SeeMemory Seat, Mirrors, and Pedals on page 13
for more information.
Engine Coolant Heater
Your vehicle may have an engine coolant heater.
If your vehicle has the DURAMAX
®Diesel
engine, see the DURAMAX®Diesel manual for
more information.
In very cold weather, 0°F (−18°C) or colder, the
engine coolant heater can help. You will get easier
starting and better fuel economy during engine
warm-up.
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Usually, the coolant heater should be plugged in a
minimum of four hours prior to starting your
vehicle. At temperatures above 32°F (0°C), use of
the coolant heater is not required. Your vehicle
may also have an internal thermostat in the
plug end of the cord. This will prevent operation of
the engine coolant heater when the temperature
is at or above 0°F (−18°C) as noted on the cord.
To Use the Engine Coolant Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical
cord. The cord is located on the driver’s
side of the engine compartment, near
the power steering uid reservoir.
3. Plug the cord 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.
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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 270orDIC Operation and
Displays (Without DIC Buttons) on page 277.
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
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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 165for 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 165.Ifyou
are pulling a trailer, seeTowing a Trailer
on page 447.
{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 165.
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 424.
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