2005 GMC ENVOY XUV engine

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.
{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 engine may be equipped with
Displacement on Demand (DoD). This system allows
the engine to operate on either four or eight cylinders,
depending on your driving demands.
The system determines when to switch into and out of
the four-cylinder mode by rst making sure that
certain enabling criteria are met, such as coolant and
oil temperatures, and the transmission being in
either THIRD (3) or FOURTH (4) gear.
When greater power demands are required, such as
accelerating from a stop, passing, or merging onto
a freeway, the system will maintain eight-cylinder
operation. When less power is required, such a
cruising at a constant vehicle speed, the system will
automatically enable the four-cylinder mode, allowing
your vehicle to achieve better fuel economy.
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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 2-37.Ifyou
are pulling a trailer, seeTowing a Trailer on
page 4-55.
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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 2-32. SeeShifting Into Park (P)
on page 2-37.
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 2-39.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 You Are Stuck: In Sand, Mud, Ice or Snow on
page 4-42.
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.
2-30

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).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.
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.
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.
2-31

Four-Wheel Drive
If your vehicle has four-wheel drive, you can send your
engine’s driving power 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 drive high (2HI) for most
normal driving conditions.
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.
Automatic Transfer Case
If your vehicle is equipped
with 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.2HI (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.
A4WD (Automatic Four-Wheel Drive):This setting
is ideal for use when road conditions are variable.
When driving your vehicle in A4WD, 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 2HI.
4HI (Four-Wheel High):Use 4HI 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.
4LO (Four-Wheel Low):This setting also engages
your front axle and delivers extra torque. It sends
maximum power to all four wheels. You might choose
4LO if you are driving off-road in deep sand, deep mud,
and climbing or descending steep hills.
2-32

Shifting Into 4LO
To shift to 4LO, 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
4LO is to have your vehicle moving 1 or 2 mph
(1.6 to 3.2 km/h). Turn the knob to 4LO. You must wait
for the 4LO indicator light to stop ashing and remain
illuminated before shifting your transmission into gear.
If you turn the knob to 4LO when your vehicle is in gear
and/or moving, the 4LO 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 4LO
To shift from 4LO to 4HI, A4WD or 2HI 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
4LO is to have your vehicle moving 1 or 2 mph
(1.6 to 3.2 km/h). Turn the knob to 4HI, A4WD or 2HI.
You must wait for the 4HI, A4WD or 2HI indicator light
to stop ashing and remain illuminated before shifting
your transmission into gear.
If the knob is turned to 4HI, A4WD or 2HI when your
vehicle is in gear and/or moving, the 4HI, A4WD or
2HI 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).
2-34

Shifting Into Park (P)
{CAUTION:
It can be 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.
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,
use the steps that follow. With 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 2-32. Always put
the shift lever fully in PARK (P) with the parking
brake rmly set. If you are pulling a trailer,
seeTowing a Trailer on page 4-55.To shift into PARK (P), do the following:
1. Hold the brake pedal down with your foot and set
the parking brake.
2. Move the shift lever into PARK (P) by pressing the
button on the side of the shift lever and pushing the
lever all the way toward the front of the vehicle.
3. Turn the ignition key to LOCK.
4. Remove the key and take it with you. You know
your vehicle is in PARK (P) if the key can be
removed from the ignition.
2-37

Leaving Your Vehicle With the
Engine Running
{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, your vehicle
will be free to roll — even if your lever is in
PARK (P) — if your transfer case is in
NEUTRAL. So be sure the transfer case is in a
drive gear — not NEUTRAL. SeeFour-Wheel
Drive on page 2-32.
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
your parking brake is rmly set before you leave it.
After you have moved 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
pressing the button on the console shift lever. If you can,
it means that the shift lever was not fully locked into
PARK (P).
Torque Lock
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, seeShifting Into Park (P)
on page 2-37.
2-38