2018 GMC YUKON XL warning

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
200 Driving and Operating
If the Vehicle Is Stuck Slowly and cautiously spin the
wheels to free the vehicle when
stuck in sand, mud, ice, or snow.
If stuck too severely for the traction
system to free the vehicle, turn the
traction system off and use the
rocking method. See Traction
Control/Electronic Stability Control
0 229 .
{ WarningIf the vehicle's tires spin at high
speed, they can explode, and you
or others could be injured. The
vehicle can overheat, causing an
engine compartment fire or other
damage. Spin the wheels as little
as possible and avoid going
above 56 km/h (35 mph).
Rocking the Vehicle to Get
it Out
Turn the steering wheel left and
right to clear the area around the
front wheels. Turn off any traction
system. Shift back and forth between R (Reverse) and a low
forward gear, spinning the wheels
as little as possible. To prevent
transmission wear, wait until the
wheels stop spinning before shifting
gears. Release the accelerator
pedal while shifting, and press
lightly on the accelerator pedal
when the transmission is in gear.
Slowly spinning the wheels in the
forward and reverse directions
causes a rocking motion that could
free the vehicle. If that does not get
the vehicle out after a few tries, it
might need to be towed out. If the
vehicle does need to be towed out,
see Towing the Vehicle 0 355 .
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 203weight of the driver, passengers,
and cargo should never exceed
the vehicle's capacity weight.
Certification/Tire Label
A vehicle specific Certification/
Tire label is attached to the
center pillar (B-pillar). The label
may shows the size of the
vehicle's original tires and the
inflation pressures needed to
obtain the gross weight capacity
of the vehicle. This is called
Gross Vehicle Weight Rating (GVWR). The GVWR includes
the weight of the vehicle, all
occupants, fuel, and cargo.
The Certification/Tire label also
may show the maximum weights
for the front and rear axles,
called Gross Axle Weight Rating
(GAWR). To find out the actual
loads on the front and rear
axles, weigh the vehicle at a
weigh station. Your dealer can
help with this. Be sure to spread
your load equally on both sides
of the centerline.
The Certification/Tire label may
also include information about
the Front Axle Reserve
Capacity.
{ Warning
Do not load the vehicle any
heavier than the Gross
Vehicle Weight Rating
(GVWR), or either the
maximum front or rear Gross
(Continued) Warning (Continued)
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.
CautionOverloading the vehicle may
cause damage. Repairs would not
be covered by the vehicle
warranty. Do not overload the
vehicle.
The label will help decide how
much cargo and installed
equipment the truck can carry.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
204 Driving and Operating Using heavier suspension
components to get added
durability might not change the
weight ratings. Ask your dealer
to help load the vehicle the
right way.
{ 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.
(Continued) Warning (Continued) .
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 Your
Vehicle for Off-Road Driving ”
under Off-Road Driving 0 192 .Starting and
Operating New Vehicle Break-In CautionThe 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 Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
206 Driving and Operating To shift out of P (Park), the ignition
must be on or in ACC/
ACCESSORY, and the brake pedal
must be applied.
Stopping the Engine/LOCK/
OFF (No Indicator Lights) : When
the vehicle is stopped, press
ENGINE START/STOP once to turn
the engine off.
If the vehicle is in P (Park), the
ignition will turn off, and Retained
Accessory Power (RAP) will remain
active. See Retained Accessory
Power (RAP) 0 212 .
If the vehicle is not in P (Park), the
ignition will return to ACC/
ACCESSORY and display the
message SHIFT TO PARK in the
Driver Information Center (DIC).
When the vehicle is shifted into
P (Park), the ignition system will
turn off.
Do not turn the engine off when the
vehicle is moving. This will cause a
loss of power assist in the brake
and steering systems and disable
the airbags. The vehicle may have an electric
steering column lock. The lock is
activated when the ignition is turned
off and either front door is opened.
A sound may be heard as the lock
actuates or releases. The steering
column lock may not release with
the wheels turned off center. If this
happens, the vehicle may not start.
Move the steering wheel from left to
right while attempting to start the
vehicle. If this does not work, the
vehicle needs service.
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), and turn the
ignition off. On vehicles with an automatic transmission, the
shift lever must be in P (Park)
to turn the ignition off.
4. Set the parking brake. See
Parking Brake 0 228 .
{ WarningTurning 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,
press and hold ENGINE START/
STOP for longer than two seconds,
or press twice in five seconds.
ACC/ACCESSORY (Amber
Indicator Light) : This mode allows
some electrical accessories to be
used when the engine is off.
With the ignition off, pressing the
button one time without the brake
pedal applied will place the ignition
system in ACC/ACCESSORY.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
208 Driving and Operating 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), and turn the
ignition to LOCK/OFF. On
vehicles with an automatic
transmission, the shift lever
must be in P (Park) to turn the
ignition switch to the LOCK/
OFF position.
4. Set the parking brake. See
Parking Brake 0 228 .
{ 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.
CautionUsing 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.
The switch stays in this position
when the engine is running. The
transmission is also unlocked in this
position on automatic transmission
vehicles.
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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 209
Starting the Engine 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 already
moving, use N (Neutral) only.
CautionDo 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.
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
0 274 . Starting Procedure (Key
Access) 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.
When the low fuel warning
lamp 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.
Caution
Cranking the engine for long
periods of time, by returning the
ignition to the START position
(Continued) Caution (Continued) 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.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
210 Driving and Operating Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Starting Procedure (Keyless
Access) 1. With the Keyless Access
system, the RKE transmitter
must be in the vehicle. Press
ENGINE START/STOP with the
brake pedal applied. When the
engine begins cranking, let go
of the button.
The idle speed will go down as
the engine gets warm. Do not
race the engine immediately
after starting it.
If the RKE transmitter is not in
the vehicle, if there is
interference, or if the RKE
battery is low, the Driver
Information Center (DIC) will
display a message. CautionCranking 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 as
you press ENGINE START/
STOP, 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 button, and
the 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.
Engine Heater
{ WarningDo not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.
If equipped, the engine heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below − 18 °C (0 °F). Vehicles
with an engine heater should be
plugged in at least four hours before
starting. There may be an internal

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 211thermostat in the plug end of the
cord, which will prevent engine
heater operation at temperatures
above − 18 °C (0 °F).
To Use the Engine Heater 1. Turn off the engine.
2. Open the hood and unwrap the
electrical cord. The cord is by
the left front fender, next to the
engine compartment fuse
block.
Check the heater cord for
damage. If it is damaged, do
not use it. See your dealer for
a replacement. Inspect the
cord for damage yearly.
3. Plug the cord into a normal,
grounded 110-volt AC outlet. { WarningImproper use of the heater cord
or an extension cord can damage
the cord and may result in
overheating and fire.
.
Plug the cord into a
three-prong electrical utility
receptacle that is protected
by a ground fault detection
function. An ungrounded
outlet could cause an
electric shock.
.
Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension
cord in good operating
condition, or using a
damaged heater or
extension cord, could make
(Continued) Warning (Continued) it overheat and cause a fire,
property damage, electric
shock, and injury.
.
Do not operate the vehicle
with the heater cord
permanently attached to the
vehicle. Possible heater
cord and thermostat
damage could occur.
.
While in use, do not let the
heater cord touch vehicle
parts or sharp edges. Never
close the hood on the
heater cord.
.
Before starting the vehicle,
unplug the cord, reattach
the cover to the plug, and
securely fasten the cord.
Keep the cord away from
any moving parts.