engine GMC YUKON XL 2018 Service Manual

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
158 Instruments and Controls .
Brakes
.
Ride Control Systems
.
Driver Assistance Systems
.
Cruise Control
.
Lighting and Bulb Replacement
.
Wiper/Washer Systems
.
Doors and Windows
.
Seat Belts
.
Airbag Systems
.
Engine and Transmission
.
Tire Pressure
.
Battery
Engine Power Messages ENGINE POWER IS REDUCED This message displays when the
vehicle's propulsion power is
reduced. Reduced propulsion power
can affect the vehicle's ability to
accelerate. If this message is on,
but there is no observed reduction
in performance, proceed to your
destination. The performance may
be reduced the next time the vehicle
is driven. The vehicle may be driven while this message is on, but
maximum acceleration and speed
may be reduced. Anytime this
message stays on, or displays
repeatedly, the vehicle should be
taken to your dealer for service as
soon as possible.
Vehicle Speed Messages SPEED LIMITED TO
XXX KM/H (MPH) This message shows that the
vehicle speed has been limited to
the speed displayed. The limited
speed is a protection for various
propulsion and vehicle systems,
such as lubrication, thermal,
suspension, Teen Driver if
equipped, or tires. Vehicle
Personalization Use the audio system controls to
access the personalization menus
for customizing vehicle features.
The following are all possible
personalization features. Depending
on the vehicle, some may not be
available.
Radio Audio System Controls
1. Touch the desired feature to
display a list of available
options.
2. Select the desired feature
setting.
3. Press
o BACK on the center
stack or touch
0 to return to
the previous menu or exit.
Turn the vehicle on to access the
Settings menu, then select
SETTINGS from the Home Page on
the infotainment display.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
174 Lighting is in the full bright position. See
Instrument Panel Illumination
Control 0 176 .
When it is bright enough outside,
the headlamps will turn off or may
change to Daytime Running
Lamps (DRL).
The automatic headlamp system
turns off when the exterior lamp
control is turned to
O or the ignition
is off.
Lights On with Wipers If the windshield wipers are
activated in daylight with the engine
on, and the exterior lamp control is
in AUTO, the headlamps, parking
lamps, and other exterior lamps
come on. The transition time for the
lamps coming on varies based on
wiper speed. When the wipers are
not operating, these lamps turn off.
Move the exterior lamp control to
Oor
; to disable this feature. Hazard Warning Flashers
| : Press this button to make the
front and rear turn signal lamps
flash on and off. Press again to turn
the flashers off.
When the hazard warning flashers
are on, the vehicle's turn signals will
not work. Turn and Lane-Change
Signals
An arrow on the instrument cluster
flashes in the direction of the turn or
lane change.
Move the turn signal lever all the
way up or down to signal a turn.
Raise or lower the lever for less
than one second until the arrow
starts to flash to signal a lane
change. This causes the turn
signals to automatically flash three
times. It will flash six times if Tow/
Haul Mode is active. Holding the
turn signal lever for more than
one second will cause the turn
signals to flash until the lever is
released.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
178 Lighting moving up or down. This is normal.
If there is a problem, an alert will be
displayed.
The battery can be discharged at
idle if the electrical loads are very
high. This is true for all vehicles.
This is because the generator
(alternator) may not be spinning fast
enough at idle to produce all the
power that is needed for very high
electrical loads.
A high electrical load occurs when
several of the following are on, such
as: headlamps, high beams, fog
lamps, rear window defogger,
climate control fan at high speed,
heated seats, engine cooling fans,
trailer loads, and loads plugged into
accessory power outlets.
EPM works to prevent excessive
discharge of the battery. It does this
by balancing the generator's output
and the vehicle's electrical needs.
It can increase engine idle speed to
generate more power, whenever
needed. It can temporarily reduce
the power demands of some
accessories. Normally, these actions occur in
steps or levels, without being
noticeable. In rare cases at the
highest levels of corrective action,
this action may be noticeable to the
driver. If so, a DIC message might
be displayed and it is recommended
that the driver reduce the electrical
loads as much as possible.
Battery Power Protection This feature shuts off the dome and
reading lamps if they are left on for
more than 10 minutes when the
ignition is off. This will keep the
battery from running down.
Exterior Lighting Battery
Saver The exterior lamps turn off about
10 minutes after the ignition is
turned off, if the parking lamps or
headlamps have been manually left
on. This protects against draining
the battery. To restart the 10-minute
timer, turn the exterior lamp control
to the
O position and then back to
the
; or
2 position. To keep the lamps on for more than
10 minutes, the ignition must be on
or in ACC/ACCESSORY.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
188 Driving and Operating
Driving and
Operating Driving Information Distracted Driving . . . . . . . . . . . . 189
Defensive Driving . . . . . . . . . . . . . 190
Drunk Driving . . . . . . . . . . . . . . . . . 190
Control of a Vehicle . . . . . . . . . . . 190
Braking . . . . . . . . . . . . . . . . . . . . . . . 190
Steering . . . . . . . . . . . . . . . . . . . . . . 191
Off-Road Recovery . . . . . . . . . . . 191
Loss of Control . . . . . . . . . . . . . . . 192
Off-Road Driving . . . . . . . . . . . . . 192
Driving on Wet Roads . . . . . . . . 197
Hill and Mountain Roads . . . . . 198
Winter Driving . . . . . . . . . . . . . . . . 198
If the Vehicle Is Stuck . . . . . . . . 200
Vehicle Load Limits . . . . . . . . . . . 200
Starting and Operating New Vehicle Break-In . . . . . . . . . 204
Adjustable Throttle and Brake
Pedal . . . . . . . . . . . . . . . . . . . . . . . 205
Ignition Positions (Keyless
Access) . . . . . . . . . . . . . . . . . . . . . 205
Ignition Positions (Key
Access) . . . . . . . . . . . . . . . . . . . . . 207
Starting the Engine . . . . . . . . . . . 209
Engine Heater . . . . . . . . . . . . . . . . 210 Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . . 212
Shifting Into Park . . . . . . . . . . . . . 212
Shifting out of Park . . . . . . . . . . . 213
Parking over Things
That Burn . . . . . . . . . . . . . . . . . . . 214
Active Fuel Management . . . . . 214
Extended Parking . . . . . . . . . . . . 214
Engine Exhaust Engine Exhaust . . . . . . . . . . . . . . 215
Running the Vehicle While
Parked . . . . . . . . . . . . . . . . . . . . . . 215
Automatic Transmission Automatic Transmission . . . . . . 216
Manual Mode . . . . . . . . . . . . . . . . . 218
Tow/Haul Mode . . . . . . . . . . . . . . . 222
Drive Systems Four-Wheel Drive . . . . . . . . . . . . . 222
Brakes Antilock Brake
System (ABS) . . . . . . . . . . . . . . . 227
Parking Brake . . . . . . . . . . . . . . . . 228
Brake Assist . . . . . . . . . . . . . . . . . . 228
Hill Start Assist (HSA) . . . . . . . . 229
Ride Control Systems
Traction Control/Electronic
Stability Control . . . . . . . . . . . . . 229 Hill Descent Control (HDC) . . . 231
Magnetic Ride Control . . . . . . . . 232
Locking Rear Axle . . . . . . . . . . . . 232
Automatic Level Control . . . . . . 232
Cruise Control Cruise Control . . . . . . . . . . . . . . . . 233
Adaptive Cruise Control . . . . . . 235
Driver Assistance Systems Driver Assistance Systems . . . 242
Assistance Systems for
Parking or Backing . . . . . . . . . . 243
Assistance Systems for
Driving . . . . . . . . . . . . . . . . . . . . . . 246
Forward Collision Alert (FCA)
System . . . . . . . . . . . . . . . . . . . . . . 246
Forward Automatic
Braking (FAB) . . . . . . . . . . . . . . . 248
Side Blind Zone
Alert (SBZA) . . . . . . . . . . . . . . . . 250
Lane Change Alert (LCA) . . . . . 250
Lane Departure
Warning (LDW) . . . . . . . . . . . . . 252
Lane Keep Assist (LKA) . . . . . . 252
Fuel Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 254
California Fuel
Requirements . . . . . . . . . . . . . . . 255
Fuels in Foreign Countries . . . 255
Fuel Additives . . . . . . . . . . . . . . . . 255

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
190 Driving and Operating Refer to the infotainment section for
more information on using that
system and the navigation system,
if equipped, including pairing and
using a cell phone.
Defensive Driving Defensive driving means “ always
expect the unexpected. ” The first
step in driving defensively is to wear
the seat belt. See Seat Belts 0 76 .
.
Assume that other road users
(pedestrians, bicyclists, and
other drivers) are going to be
careless and make mistakes.
Anticipate what they might do
and be ready.
.
Allow enough following distance
between you and the driver in
front of you.
.
Focus on the task of driving.
Drunk Driving Death and injury associated with
drinking and driving is a global
tragedy. { WarningDrinking and then driving is very
dangerous. Your reflexes,
perceptions, attentiveness, and
judgment can be affected by even
a small amount of alcohol. You
can have a serious — or even
fatal — collision if you drive after
drinking.
Do not drink and drive or ride with
a driver who has been drinking.
Ride home in a cab; or if you are
with a group, designate a driver
who will not drink.
Control of a Vehicle Braking, steering, and accelerating
are important factors in helping to
control a vehicle while driving.
Braking Braking action involves perception
time and reaction time. Deciding to
push the brake pedal is perception
time. Actually doing it is
reaction time. Average driver reaction time is
about three-quarters of a second. In
that time, a vehicle moving at
100 km/h (60 mph) travels 20 m
(66 ft), which could be a lot of
distance in an emergency.
Helpful braking tips to keep in mind
include:
.
Keep enough distance between
you and the vehicle in front
of you.
.
Avoid needless heavy braking.
.
Keep pace with traffic.
If the engine ever stops while the
vehicle is being driven, brake
normally but do not pump the
brakes. Doing so could make the
pedal harder to push down. If the
engine stops, there will be some
power brake assist but it will be
used when the brake is applied.
Once the power assist is used up, it
can take longer to stop and the
brake pedal will be harder to push.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 193.
Read all the information about
four-wheel-drive vehicles in this
manual.
.
Remove any underbody air
deflector, if equipped. Re-attach
the air deflector after off-road
driving.
.
Know the local laws that apply to
off-road driving.
To gain more ground clearance if
needed, it may be necessary to
remove the front fascia lower air
dam, if equipped. However, driving
without the air dam reduces fuel
economy.
Caution
Operating the vehicle for
extended periods without the front
fascia lower air dam installed can
cause improper airflow to the
engine. Reattach the front fascia
air dam after off-road driving. Loading the Vehicle for
Off-Road Driving
{ Warning.
Unsecured cargo on the
load floor can be tossed
about when driving over
rough terrain. You or your
passengers can be struck
by flying objects. Secure the
cargo properly.
.
Keep cargo in the cargo
area as far forward and as
low as possible. The
heaviest things should be
on the floor, forward of the
rear axle.
.
Heavy loads on the roof
raise the vehicle's center of
gravity, making it more likely
to roll over. You can be
seriously or fatally injured if
the vehicle rolls over. Put
heavy loads inside the
cargo area, not on the roof. For more information about loading
the vehicle, see Vehicle Load Limits
0 200 and Tires 0 320 .
Environmental Concerns .
Always use established trails,
roads, and areas that have been
set aside for public off-road
recreational driving and obey all
posted regulations.
.
Do not damage shrubs, flowers,
trees, or grasses or disturb
wildlife.
.
Do not park over things that
burn. See Parking over Things
That Burn 0 214 .
Driving on Hills Driving safely on hills requires good
judgment and an understanding of
what the vehicle can and cannot do.
{ Warning
Many hills are simply too steep
for any vehicle. Driving up hills
can cause the vehicle to stall.
Driving down hills can cause loss
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
194 Driving and Operating Warning (Continued)of control. Driving across hills can
cause a rollover. You could be
injured or killed. Do not drive on
steep hills.
Before driving on a hill, assess the
steepness, traction, and
obstructions. If the terrain ahead
cannot be seen, get out of the
vehicle and walk the hill before
driving further.
When driving on hills:
.
Use a low gear and keep a firm
grip on the steering wheel.
.
Maintain a slow speed.
.
When possible, drive straight up
or down the hill.
.
Slow down when approaching
the top of the hill.
.
Use headlamps even during the
day to make the vehicle more
visible. { WarningDriving to the top of a hill at high
speed can cause an accident.
There could be a drop-off,
embankment, cliff, or even
another vehicle. You could be
seriously injured or killed. As you
near the top of a hill, slow down
and stay alert.
.
Never go downhill forward or
backward with either the
transmission or transfer case in
N (Neutral). The brakes could
overheat and you could lose
control.
{ Warning
If the vehicle has the two-speed
automatic or electronic transfer
case, shifting the transfer case to
N (Neutral) can cause your
vehicle to roll even if the
transmission is in P (Park). This is
because the N (Neutral) position
(Continued) Warning (Continued) on the transfer case overrides the
transmission. You or someone
else could be injured. If leaving
the vehicle, set the parking brake
and shift the transmission to
P (Park). Shift the transfer case to
any position but N (Neutral).
.
When driving down a hill, keep
the vehicle headed straight
down. Use a low gear because
the engine will work with the
brakes to slow the vehicle and
help keep the vehicle under
control.
{ Warning
Heavy braking when going down
a hill can cause your brakes to
overheat and fade. This could
cause loss of control and you or
others could be injured or killed.
Apply the brakes lightly when
(Continued)

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
Driving and Operating 195Warning (Continued)descending a hill and use a low
gear to keep vehicle speed under
control.
If the vehicle stalls on a hill:
1. Apply the brakes to stop the
vehicle, and then apply the
parking brake.
2. Shift into P (Park) and then
restart the engine.
.
If driving uphill when the
vehicle stalls, shift to
R (Reverse), release the
parking brake, and back
straight down.
.
Never try to turn the vehicle
around. If the hill is steep
enough to stall the vehicle,
it is steep enough to cause
it to roll over.
.
If you cannot make it up the
hill, back straight down
the hill. .
Never back down a hill in
N (Neutral) using only the
brake. The vehicle can roll
backward quickly and you
could lose control.
.
If driving downhill when the
vehicle stalls, shift to a
lower gear, release the
parking brake, and drive
straight down the hill.
3. If the vehicle cannot be
restarted after stalling, set the
parking brake, shift into
P (Park), and turn the
vehicle off.
3.1. Leave the vehicle and
seek help.
3.2. Stay clear of the path the
vehicle would take if it
rolled downhill.
.
Avoid turns that take the vehicle
across the incline of the hill.
A hill that can be driven straight
up or down might be too steep to
drive across. Driving across an
incline puts more weight on the downhill wheels, which could
cause a downhill slide or a
rollover.
.
Surface conditions can be a
problem. Loose gravel, muddy
spots, or even wet grass can
cause the tires to slip sideways,
downhill. If the vehicle slips
sideways, it can hit something
that will trip it — a rock, a rut,
etc. — and roll over.
.
Hidden obstacles can make the
steepness of the incline more
severe. If a rock is driven across
with the uphill wheels, or if the
downhill wheels drop into a rut
or depression, the vehicle can tilt
even more.
.
If an incline must be driven
across, and the vehicle starts to
slide, turn downhill. This should
help straighten out the vehicle
and prevent the side slipping.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
196 Driving and Operating
{ WarningGetting out of the vehicle on the
downhill side when stopped
across an incline is dangerous.
If the vehicle rolls over, you could
be crushed or killed. Always get
out on the uphill side of the
vehicle and stay well clear of the
rollover path.
Driving in Mud, Sand, Snow,
or Ice Use a low gear when driving in
mud — the deeper the mud, the
lower the gear. Keep the vehicle
moving to avoid getting stuck.
Traction changes when driving on
sand. On loose sand, such as on
beaches or sand dunes, the tires
tend to sink into the sand. This
affects steering, accelerating, and
braking. Drive at a reduced speed
and avoid sharp turns or abrupt
maneuvers. Traction is reduced on hard packed
snow and ice and it is easy to lose
control. Reduce vehicle speed when
driving on hard packed snow
and ice.
{ WarningDriving on frozen lakes, ponds,
or rivers can be dangerous. Ice
conditions vary greatly and the
vehicle could fall through the ice;
you and your passengers could
drown. Drive your vehicle on safe
surfaces only.
Driving in Water
{ Warning
Driving through rushing water can
be dangerous. Deep water can
sweep your vehicle downstream
and you and your passengers
could drown. If it is only shallow
water, it can still wash away the
ground from under your tires.
(Continued) Warning (Continued) Traction could be lost, and the
vehicle could roll over. Do not
drive through rushing water.
CautionDo 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.
If the standing water is not too deep,
drive through it slowly. At faster
speeds, water can get into the
engine and cause it to stall. Stalling
can occur if the exhaust pipe is
under water. Do not turn off the
ignition when driving through water.
If the exhaust pipe is under water,
the engine will not start. When going
through water, the brakes get wet
and it may take longer to stop. See
“ Driving on Wet Roads ” later in this
section.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
198 Driving and Operating
Hill and Mountain Roads Driving on steep hills or through
mountains is different than driving
on flat or rolling terrain. Tips include:
.
Keep the vehicle serviced and in
good shape.
.
Check all fluid levels and brakes,
tires, cooling system, and
transmission.
.
Shift to a lower gear when going
down steep or long hills.
{ WarningUsing the brakes to slow the
vehicle on a long downhill slope
can cause brake overheating, can
reduce brake performance, and
could result in a loss of braking.
Shift the transmission to a lower
gear to let the engine assist the
brakes on a steep downhill slope. { WarningCoasting downhill in N (Neutral)
or with the ignition off is
dangerous. This can cause
overheating of the brakes and
loss of steering assist. Always
have the engine running and the
vehicle in gear.
.
Drive at speeds that keep the
vehicle in its own lane. Do not
swing wide or cross the
center line.
.
Be alert on top of hills;
something could be in your lane
(e.g., stalled car, accident).
.
Pay attention to special road
signs (e.g., falling rocks area,
winding roads, long grades,
passing or no-passing zones)
and take appropriate action. Winter Driving Driving on Snow or Ice Snow or ice between the tires and
the road creates less traction or
grip, so drive carefully. Wet ice can
occur at about 0 °C (32 °F) when
freezing rain begins to fall. Avoid
driving on wet ice or in freezing rain
until roads can be treated.
For Slippery Road Driving:
.
Accelerate gently. Accelerating
too quickly causes the wheels to
spin and makes the surface
under the tires slick.
.
Turn on Traction Control. See
Traction Control/Electronic
Stability Control 0 229 .
.
The Antilock Brake System
(ABS) improves vehicle stability
during hard stops, but the
brakes should be applied sooner
than when on dry pavement.
See Antilock Brake System
(ABS) 0 227 .