GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
248 Driving and Operating
Caution
Do not drive through standing
water if it is deep enough to cover
the wheel hubs, axles, or exhaust
pipe. Deep water can damage the
axle and other vehicle parts.
There are recovery hooks at the
front of the vehicle. Use them if the
vehicle is stuck off-road and needs
to be pulled some place to continue
driving.
Vehicle Load Limits
It is very important to know how
much weight the vehicle can
carry. This weight is called the
vehicle capacity weight and
includes the weight of all
occupants, cargo, and all
nonfactory-installed options. Two labels on the vehicle may
show how much weight it was
designed to carry: the Tire and
Loading Information label and
the Certification/Tire label.
{Warning
Do not load the vehicle any
heavier than the Gross
Vehicle Weight Rating
(GVWR), or either the
maximum front or rear Gross
Axle Weight Rating (GAWR).
This can cause systems to
break and change the way the
vehicle handles. This could
cause loss of control and a
crash. Overloading can also
reduce stopping distance,
damage the tires, and shorten
the life of the vehicle.
Tire and Loading Information
Label
Label Example
A vehicle-specific Tire and
Loading Information label is
attached to the center pillar
(B-pillar). The Tire and Loading
Information label shows the
number of occupant seating
positions (1), and the maximum
vehicle capacity weight (2) in
kilograms and pounds.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
252 Driving and Operating
{Warning
Things you put inside the
vehicle can strike and injure
people in a sudden stop or
turn, or in a crash.
.Put things in the cargo
area of the vehicle. Try to
spread the weight evenly.
.Never stack heavier
things, like suitcases,
inside the vehicle so that
some of them are above
the tops of the seats.
.Do not leave an
unsecured child restraint
in the vehicle.
.When you carry
something inside the
vehicle, secure it
whenever you can.
.Do not leave a seat
folded down unless you
need to. There is also important loading
information for off-road driving in
this manual. See
“Loading the
Vehicle for Off-Road Driving“
under Off-Road Driving 0239.
Two-Tiered Loading
Depending on the model of the
pickup, an upper load platform
can be created by positioning
three or four 5 cm (2 in) by
15 cm (6 in) wooden planks
across the width of the pickup
box. The planks must be
inserted in the pickup box
depressions.
When using this upper load
platform, be sure the load is
securely tied down to prevent it
from shifting. The load's center
of gravity should be positioned
in a zone over the rear axle. The
zone is located in the area
between the front of each wheel
well and the rear of each wheel well. The center of gravity height
must not extend above the top
of the pickup box flareboard.
Any load that extends beyond
the vehicle's taillamp area must
be properly marked according to
local laws and regulations.
Remember not to exceed the
Gross Axle Weight
Rating (GAWR) of the front or
rear axle.
Add-On Equipment
When carrying removable items,
a limit on how many people
carried inside the vehicle may
be necessary. Be sure to weigh
the vehicle before buying and
installing the new equipment.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 255
exceed the truck's cargo weight
rating, and the camper's center
of gravity (1) should fall within
the truck's recommended center
of gravity zone (2) when
installed.
Any accessories or other
equipment that are added to the
vehicle must be weighed. Then,
subtract this extra weight from
the CWR. This extra weight may
shorten the center of gravity
zone of the vehicle.
If the slide-in camper and its
load weighs less than the CWR,
the center of gravity zone for the
vehicle may be larger.
Secure loose items to prevent
weight shifts that could affect the
balance of the vehicle. When the
truck-camper is loaded, drive to
a scale and weigh on the frontand on the rear wheels
separately to determine axle
loads. Individual axle loads
should not exceed either of the
gross axle weight ratings
(GAWR). The total axle loads
should not exceed the vehicle's
gross vehicle weight rating
(GVWR). These ratings are
given on the Certification/
Tire label attached to the
B-pillar. See
“Certification/Tire
Label” underVehicle Load
Limits 0248. If weight ratings
are exceeded, move or remove
items to bring all weights below
the ratings.
See your dealer for more
information on curb weights,
cargo weights, Cargo Weight
Rating, and the correct center of
gravity zone.Starting and
Operating
New Vehicle Break-In
Caution
The vehicle does not need an
elaborate break-in. But it will
perform better in the long run if
you follow these guidelines:
. Keep the vehicle speed at
88 km/h (55 mph) or less for
the first 805 km (500 mi).
. Do not drive at any one
constant speed, fast or slow,
for the first 805 km (500 mi).
Do not make full-throttle
starts. Avoid downshifting to
brake or slow the vehicle.
. Avoid making hard stops for
the first 322 km (200 mi) or
so. During this time the new
brake linings are not yet
broken in. Hard stops with
new linings can mean
(Continued)
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 257
This position locks the ignition and
steering wheel. It also locks the
transmission. The key can be
removed in 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
does not work, then the vehicle
needs service.
Do not turn the engine off when the
vehicle is moving. This may cause a
loss of power assist in the brake
and steering systems and disable
the airbags.
If the vehicle must be shut off in an
emergency:1. Brake using a firm and steady pressure. Do not pump the
brakes repeatedly. This may
deplete power assist, requiring
increased brake pedal force.
2. Shift the vehicle to N (Neutral). This can be done while the
vehicle is moving. After shifting to N (Neutral), firmly apply the
brakes and steer the vehicle to
a safe location.
3. Come to a complete stop. Shift to P (Park). Turn the ignition to
LOCK/OFF.
4. Set the parking brake. See Parking Brake 0281.
The shift lever must be in P (Park)
to turn the ignition switch to
LOCK/OFF.
{Warning
Turning off the vehicle while
moving may cause loss of power
assist in the brake and steering
systems and disable the airbags.
While driving, only shut the
vehicle off in an emergency.
If the vehicle cannot be pulled over,
and must be shut off while driving,
turn the ignition to ACC/
ACCESSORY.
Caution
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.
1 (ACC/ACCESSORY) : This
position lets things like the radio
and the windshield wipers operate
while the engine is off. It also
unlocks the steering wheel. Use this
position if the vehicle must be
pushed or towed.
2 (ON/RUN) : This position can be
used to operate the electrical
accessories and to display some
instrument cluster warning and
indicator lights. This position can
also be used for service and
diagnostics, and to verify the proper
operation of the malfunction
indicator lamp as may be required
for emission inspection purposes.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
258 Driving and Operating
The switch stays in this position
when the engine is running. The
transmission is also unlocked in this
position.
If the key is left in the ACC/
ACCESSORY or ON/RUN position
with the engine off, the battery could
be drained. The vehicle may not
start if the battery is allowed to drain
for an extended period of time.
3 (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 and the
ignition is in ACC/ACCESSORY or
LOCK/OFF, and the key is in the
ignition.
Starting the Engine
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
For an eAssist vehicle, see the
Silverado/Sierra eAssist
supplement.
Caution
If you add electrical parts or
accessories, you could change
the way the engine operates. Any
resulting damage would not be
covered by the vehicle warranty.
See Add-On Electrical Equipment
0 336.
Caution
If the steering wheel is turned
until it reaches the end of its
travel, and is held in that position
while starting the vehicle, damage
may occur to the power steering
system and there may be loss of
power steering assist.
Move the shift lever to P (Park) or
N (Neutral). To restart the engine
when the vehicle is already moving,
use N (Neutral) only.
Caution
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.
Starting Procedure
1. 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.
When the low fuel warning light
is on and the FUEL LEVEL
LOW message is displayed in
the Driver Information Center
(DIC), hold the ignition switch
in the START position to
continue engine cranking.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 259
Caution
Cranking the engine for long
periods of time, by returning the
ignition 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 five to 10 seconds,
especially in very cold weather
(below −18 °C or 0 °F), it could
be flooded with too much
gasoline. Try pushing the
accelerator pedal all the way to
the floor and holding it there
while holding the key in START
for up to 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
briefly 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.
Fast Idle System
If equipped, this feature is available
only with cruise control. The manual
fast idle switch is operated using the
cruise control buttons on the left
side of the steering wheel.
This system can be used to
increase engine idle speed
whenever the following conditions
are met:
.
The parking brake is set.
. The brake pedal is not pressed.
. The vehicle must not be moving
and the accelerator must not be
pressed. To control the fast idle:
.
To enable the Fast Idle System,
press and release the cruise
control on/off button and ensure
that the switch indicator light
is lit.
. Press and release the cruise
control SET- button. Engine
speed will be held at
approximately 1200 rpm.
One of the following actions will turn
off the fast idle:
. Pressing the brake.
. Selecting the cruise control
cancel button.
. Releasing the parking brake.
. Moving the transmission shift
lever out of P (Park) or
N (Neutral).
. Selecting the cruise control on/
off button when it was
previously on.
. Pressing the cruise control SET-
button a second time.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
262 Driving and Operating
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 in the
area where you will be parking the
vehicle for the best advice on this.
Shifting Into Park
{Warning
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle can
roll. 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, use the steps
that follow. With four-wheel drive,
if the transfer case is in
N (Neutral), the vehicle will be
free to roll, even if the shift lever (Continued)
Warning (Continued)
is in P (Park). Be sure the transfer
case is in a drive gear. If towing a
trailer, seeDriving Characteristics
and Towing Tips 0303.
1. Hold the brake pedal down, then set the parking brake. See
Parking Brake 0281.
2. Move the shift lever into the P (Park) position by pulling the
shift lever toward you and
moving it up as far as it will go.
3. Be sure the transfer case (if equipped) is in a drive gear–
not in N (Neutral).
4. Turn the ignition off.
5. Remove the key and take it with you. If you can leave the
vehicle with the ignition key in
your hand, the vehicle is in
P (Park).
Leaving the Vehicle with the
Engine Running
{Warning
It can be dangerous to leave the
vehicle with the engine running.
The vehicle could move suddenly
if the shift lever is not fully in
P (Park) with the parking brake
firmly set.
If you have four-wheel drive and
the transfer case is in N (Neutral),
the vehicle will be free to roll,
even if the shift lever is in
P (Park). So be sure the transfer
case is in a drive gear –not in
N (Neutral).
And, if you leave the vehicle with
the engine running, it could
overheat and even catch fire. You
or others could be injured. Do not
leave the vehicle with the engine
running unless you have to.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349177) - 2018 - CRC - 10/17/17
Driving and Operating 265
Warning (Continued)
.There are holes or openings
in the vehicle body from
damage or aftermarket
modifications that are not
completely sealed.
If unusual fumes are detected or
if it is suspected that exhaust is
coming into the vehicle: . Drive it only with the
windows completely down.
. Have the vehicle repaired
immediately.
Never park the vehicle with the
engine running in an enclosed
area such as a garage or a
building that has no fresh air
ventilation.
Running the Vehicle
While Parked
It is better not to park with the
engine running.
If the vehicle is left with the engine
running, follow the proper steps to
be sure the vehicle will not move.
See Shifting Into Park 0262 and
Engine Exhaust 0264.
If parking on a hill and pulling a
trailer, see Driving Characteristics
and Towing Tips 0303.
Automatic
Transmission
If equipped, there is an electronic
shift lever position indicator within
the instrument cluster. This display
comes on when the ignition key is
turned on.
There are several different positions
for the shift lever.
Heavy-Duty 6-Speed Automatic
Transmission Shown, Others
Similar
See “Range Selection Mode” under
Manual Mode 0268.
P : This position locks the rear
wheels. Use P (Park) when starting
the engine because the vehicle
cannot move easily.