engine CHEVROLET TAHOE 2009 3.G User Guide

Starting and Operating Your
Vehicle
New Vehicle Break-In
Notice:The 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. SeeTowing
a Trailer on page 4-50for the trailer towing
capabilities of the vehicle and more information.
Following break-in, engine speed and load can
be gradually increased.
Ignition Positions
The ignition switch has
four different positions.
To shift out of P (Park), the ignition must be in ON/RUN
or ACC/ACCESSORY and the regular brake pedal
must be applied.
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A (LOCK/OFF):This position locks the ignition. It also
locks the transmission on automatic transmission
vehicles. The key can be removed in LOCK/OFF.
On vehicles with an automatic transmission, the shift
lever must be in P (Park) to turn the ignition switch
to LOCK/OFF.
The steering can bind with the wheels turned off center.
If this happens, move the steering wheel from right to
left while turning the key to ACC/ACCESSORY. If
this doesn’t work, then the vehicle needs service.
Notice:Using a tool to force the key to turn in the
ignition could cause damage to the switch or break
the key. Use the correct key, make sure it is all the
way in, and turn it only with your hand. If the key
cannot be turned by hand, see your dealer/retailer.
B (ACC/ACCESSORY):This position lets things like the
radio and the windshield wipers operate while the
engine is off. Use this position if the vehicle must be
pushed or towed.C (ON/RUN):This position can be used to operate the
electrical accessories and to display some instrument
panel cluster warning and indicator lights. The
switch stays in this position when the engine is running.
The transmission is also unlocked in this position on
automatic transmission vehicles.
If you leave the key in the ACC/ACCESSORY or
ON/RUN position with the engine off, the battery could
be drained. You may not be able to start the vehicle
if the battery is allowed to drain for an extended period
of time.
D (START):This is the position that starts the engine.
When the engine starts, release the key. The ignition
switch returns to ON/RUN for driving.
A warning tone will sound when the driver door is
opened, the ignition is in ACC/ACCESSORY or
LOCK/OFF and the key is in the ignition.
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Retained Accessory Power (RAP)
The following vehicle accessories can be used for up to
10 minutes after the engine is turned off:
Audio System
Power Windows
OnStar®System (if equipped)
Sunroof (if equipped)
These features work when the key is in ON/RUN or
ACC/ACCESSORY. Once the key is turned from
ON/RUN to LOCK/OFF, the windows and sunroof
continue to work up to 10 minutes until any door
is opened. The radio continues to work for up to
10 minutes or until the driver door is opened.
Starting the Engine
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
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 are already moving, use
N (Neutral) only.
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.
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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 the
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.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:The engine is designed to work with the
electronics in the vehicle. If you add electrical parts
or accessories, you could change the way the
engine operates. Before adding electrical equipment,
check with your dealer/retailer. If you do not, the
engine might not perform properly. Any resulting
damage would not be covered by the vehicle
warranty.
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Adjustable Throttle and Brake Pedal
On vehicles with this feature, you can change the
position of the throttle and brake pedals.
No adjustment to the pedals can be made when the
vehicle is in R (Reverse) or while using the cruise
control.
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.The vehicle may have a memory function which lets
pedal settings be saved and recalled. SeeMemory Seat,
Mirrors, and Pedals on page 1-8for more information.
Engine Coolant Heater
The engine coolant heater can provide easier starting
and better fuel economy during engine warm-up in cold
weather conditions at or below 0°F (−18°C). Vehicles
with an engine heater should be plugged in at least
four hours before starting. An internal thermostat in the
plug-end of the cord may exist which will prevent
engine coolant heater operation at temperatures
above 0°F (−18°C).
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.
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{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.
The length of time the heater should remain plugged in
depends on several factors. Ask a dealer/retailer in
the area where you will be parking the vehicle for the
best advice on this.
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 3-52orDIC Operation and Displays
(Without DIC Buttons) on page 3-58for more information
on using this display.
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Automatic Transmission Operation
If the vehicle is a Two-mode Hybrid, see the Two-mode
Hybrid manual for more information.
If the 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 ON/RUN position.
There are several different positions for the shift lever.
See “Range Selection Mode” later in this section.
P (Park):This position locks the rear wheels. It is the
best position to use when starting the engine because
the vehicle cannot move easily. 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
P (Park). See Torque Lock (Automatic Transmission)
underShifting Into Park on page 2-47for more
information.
Hydra-Matic
®4-Speed
Automatic Transmission
Hevay Duty 6-Speed Automatic Transmission
Shown (Light Duty Similar)
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{CAUTION:
It is dangerous to get out of the vehicle if the shift
lever is not fully in P (Park) with the parking brake
rmly set. The vehicle can roll.
Do not leave the 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 the
vehicle will not move, even when you are on fairly
level ground, always set the parking brake and
move the shift lever to P (Park). SeeShifting Into
Park on page 2-47. If you are pulling a trailer, see
Towing a Trailer on page 4-50.
{CAUTION:
If you have Four-Wheel Drive, the vehicle
will be free to roll — even if the shift lever is in
P (Park) — if the 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. See
Shifting Into Park on page 2-47.
R (Reverse):Use this gear to back up.
Notice:Shifting to R (Reverse) while the vehicle is
moving forward could damage the transmission.
The repairs would not be covered by the vehicle
warranty. Shift to R (Reverse) only after the vehicle
is stopped.
To rock the vehicle back and forth to get out of snow,
ice, or sand without damaging the transmission,
seeIf Your Vehicle is Stuck in Sand, Mud, Ice, or Snow
on page 4-31.
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N (Neutral):In this position, the engine does not
connect with the wheels. To restart the engine when the
vehicle is already moving, use N (Neutral) only. Also,
use N (Neutral) when the vehicle is being towed.
{CAUTION:
Shifting into a drive gear while the engine is
running at high speed is dangerous. Unless your
foot is rmly on the brake pedal, the vehicle could
move very rapidly. You could lose control and hit
people or objects. Do not shift into a drive gear
while the engine is running at high speed.
Notice:Shifting out of P (Park) or N (Neutral) with
the engine running at high speed may damage
the transmission. The repairs would not be covered
by the vehicle warranty. Be sure the engine is
not running at high speed when shifting the vehicle.D (Drive):This position is for normal driving. It provides
the best fuel economy. If you need more power for
passing, and you are:
Going less than about 35 mph (55 km/h), push the
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
By doing this, the vehicle shifts down to the next
gear and has more power.
D (Drive) can be used when towing a trailer, carrying a
heavy load, driving on steep hills, or for off-road
driving. You might want to shift the transmission to a
lower gear selection if the transmission shifts too often.
Downshifting the transmission in slippery road
conditions could result in skidding. See Skidding under
Loss of Control on page 4-11.
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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 vehicle’s 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 the 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 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 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 (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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