2006 GMC ENVOY engine

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 closer for better pedal reach. This feature can
be programmed to work with the memory function,
if equipped, on your vehicle. SeeMemory Seat on
page 2-62.
The vehicle must be in PARK (P) for this feature to
operate.
The switch used to adjust
the pedals is located on
the steering column.
Press the switch forward or backward to move the
pedals closer or farther away from you.
Engine Coolant Heater
Your vehicle may have an engine coolant heater. 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. 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.
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, behind the battery.
3. Plug it 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.
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.
Displacement on Demand™ (DoD™)
Your vehicle’s V8 engine may have Displacement on
Demand™ (DoD™). This system allows the engine
to operate on either all or half of its cylinders, depending
on your 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.
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Automatic Transmission Operation
There are several different positions for your gear
shift lever.
PARK (P):This position locks the rear wheels. It is the
best position to use when you start the engine
because your vehicle cannot move easily.
{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) on
page 2-32. If you are pulling a trailer, see
Towing a Trailer on page 4-56.
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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 — not in NEUTRAL. SeeFour-Wheel
Drive on page 2-27. SeeShifting Into Park (P)
on page 2-32.
Ensure the shift lever is fully in PARK (P) before starting
the engine. Your vehicle has an automatic transmission
shift lock control system. You have to fully apply the
regular brakes before you can shift from PARK (P) when
the ignition key is in RUN. If you cannot shift out of
PARK (P), ease pressure on the shift lever, press the
button on the shift lever and push the shift lever all
the way into PARK (P) as you maintain brake
application. Move the shift lever into the gear you wish.
SeeShifting Out of Park (P) on page 2-33.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 4-44.
NEUTRAL (N):In this position, the engine does not
connect with the wheels. To restart when you are
already moving, use NEUTRAL (N) only.
{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.
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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 the
accelerator pedal about halfway down.
Going about 35 mph (55 km/h) or more, push the
accelerator all the way down.
You will shift down to the next gear and have
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.
THIRD (3):This position is also used for normal driving.
However, it offers more power and lower fuel economy
than DRIVE (D).
To shift to the THIRD (3) position, you must rst press
the large button on the shift handle. While the button
is pressed, move the shifter in the THIRD (3) position.SECOND (2):This position gives you more power but
lower fuel economy than THIRD (3). You can use
SECOND (2) on hills. It can help control your speed as
you go down steep mountain roads, but then you
would also want to use the brakes off and on.
To shift to the SECOND (2) position, you must rst
press the large button on the shift handle. While
the button is pressed, move the shifter in the
SECOND (2) position.
You can also use SECOND (2) for starting the vehicle
from a stop on slippery road surfaces.
FIRST (1):This position gives you even more power
but lower fuel economy than SECOND (2). You can use
it on very steep hills, or in deep snow or mud. If the
selector lever is put in FIRST (1) while the vehicle
is moving forward, the transmission will not shift into
rst gear until the vehicle is going slowly enough.
To shift to the FIRST (1) position, you must rst press
the large button on the shift handle. While the button is
pressed, move the shifter in the FIRST (1) position.
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.
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Four-Wheel Drive
If your vehicle has four-wheel drive, the engine’s driving
power can be sent to all four wheels for extra traction.
To get the most satisfaction out of four-wheel drive, you
must be familiar with its operation. Read the part that
follows before using four-wheel drive. You should
use Two-Wheel High for most normal driving conditions.
Notice:Driving on clean, dry pavement in
Four-Wheel-Drive High or Four-Wheel-Drive Low 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 High or
Four-Wheel-Drive Low for extended periods of time.
Automatic Transfer Case
Your vehicle will have one of the following transfer
case knobs.
If your vehicle has four-wheel drive, the transfer case
knob is located to the right of the steering wheel on the
instrument panel. Use this knob to shift into and out
of four-wheel drive.
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If the service Four-Wheel Drive Warning Light on the
instrument panel cluster stays on, you should take your
vehicle to your dealer for service. SeeService
Four-Wheel Drive Warning Light on page 3-48for
further information.
Shifting Into Four-Wheel High or Automatic
Four-Wheel Drive
Turn the knob to Four-Wheel High or Automatic
Four-Wheel Drive. This can be done at any speed
unless you are shifting out of Four-Wheel Low. The
indicator light will ash while shifting. It will remain on
when the shift is complete.
Shifting Into Two-Wheel High
Turn the knob to Two-Wheel High. This can be done at
any speed unless you are shifting out of Four-Wheel Low.
Shifting Into Four-Wheel Low
To shift to Four-Wheel Low, the vehicle’s engine must
be running and the vehicle must be stopped or
moving less than 2 mph (3.2 km/h) with the transmission
in NEUTRAL (N). The preferred method for shifting
into Four-Wheel Low is to have your vehicle moving 1 or
2 mph (1.6 to 3.2 km/h). Turn the knob to Four-Wheel
Low. You must wait for the Four-Wheel Low indicator
light to stop ashing and stay on before shifting
the transmission into gear.If you turn the knob to Four-Wheel Low when your
vehicle is in gear and/or moving, the Four-Wheel Low
indicator light will ash for 30 seconds and not complete
the shift unless your vehicle is moving less than
2 mph (3.2 km/h) and the transmission is in
NEUTRAL (N). After 30 seconds, the transfer case will
return to the setting last chosen.
Shifting Out of Four-Wheel Low
To shift from Four-Wheel Low to Four-Wheel High, Auto
Four-Wheel Drive, or Two-Wheel High, your vehicle
must be stopped or moving less than 2 mph (3.2 km/h)
with the transmission in NEUTRAL (N) and the
engine running. The preferred method for shifting out of
Four-Wheel Low is to have your vehicle moving
1 or 2 mph (1.6 to 3.2 km/h). Turn the knob to
Four-Wheel High, Auto Four-Wheel Drive, or Two-Wheel
High. You must wait for the Four-Wheel High, Auto
Four-Wheel Drive, or Two-Wheel High indicator light to
stop ashing and stay off before shifting your
transmission into gear.
If the knob is turned to Four Wheel-High, Auto
Four-Wheel Drive, or Two-Wheel High when your
vehicle is in gear and/or moving, the Four-Wheel High,
Auto Four-Wheel Drive, or Two-Wheel High indicator
light will ash for 30 seconds. It will not complete
the shift unless your vehicle is moving less than 2 mph
(3.2 km/h) with the transmission in NEUTRAL (N).
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Shifting into NEUTRAL
Before shifting the transfer case to NEUTRAL, rst
make sure the vehicle is parked so that it will not roll.
1. Set the parking brake.
2. Start the vehicle.
3. Put the transmission in NEUTRAL (N).
4. Shift the transfer case to Two-Wheel High.
5. Turn the transfer case knob all of the way past
Four-Wheel Low and hold it there for a minimum
of 10 seconds. The neutral indicator light will
come on.
6. With the engine running, shift the transmission to
REVERSE (R) for one second, then shift the
transmission to DRIVE (D) for one second, to
ensure that the transfer case is in NEUTRAL.
7. Turn the engine off, by turning the key to
ACCESSORY.
8. Place the transmission shift lever in PARK (P).
9. Turn the ignition to LOCK.
Shifting Out of NEUTRAL
To shift the transfer case out of NEUTRAL, do the
following:
1. Set the parking brake and apply the regular
brake pedal.
2. Turn the ignition to RUN with the engine off.
3. Put the transmission in NEUTRAL (N).
4. Turn the transfer case knob to the desired position
(Two-Wheel High, Four-Wheel High, or Auto
Four-Wheel Drive).
5. After the transfer case has shifted out of NEUTRAL,
the indicator light will go out.
6. Release the parking brake.
7. Start the engine and shift the transmission to the
desired position.
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