2007 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.
If your vehicle has this feature, it can be
programmed to work with the memory function.
SeeMemory Seat, Mirrors, and Pedals on page 12.
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. 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 next to the
battery box facing the engine.
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.
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 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 127.
If you are pulling a trailer, seeTowing a
Trailer on page 362.
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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 122. SeeShifting Into Park (P) on
page 127.
Make sure 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 rst and
then press the shift lever button 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 and push the shift
lever all the way into PARK (P) as you maintain
brake application. Then press the shift lever button
and move the shift lever into another gear. See
Shifting Out of Park (P) on page 129.
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 348.
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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.
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.
It provides the best fuel economy for your vehicle.
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.
Downshifting the transmission in slippery road
conditions could result in skidding, see “Skidding”
underLoss of Control on page 318.
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. It reduces vehicle speed more than
DRIVE (D) without using your brakes. You might
choose THIRD (3) instead of DRIVE (D) when
driving on hilly, winding roads, when towing
a trailer, so there is less shifting between gears
and when going down a steep hill.
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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
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
2
m(Two-Wheel High):This setting is for
driving in most street and highway situations.
Your front axle is not engaged in two-wheel drive.
It also provides the best fuel economy.
AUTO (Automatic Four-Wheel Drive):This
setting is ideal for use when road conditions are
variable. When driving your vehicle in automatic
four-wheel drive, the front axle is engaged, but the
vehicle’s power is sent to the rear wheels.
When the vehicle senses 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.
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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.
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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).
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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