warning GMC YUKON XL 2018 Owners Manual

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/21/17
274 Driving and Operating
{ WarningUse of electronic trailer sway
control devices could result in
reduced trailer brake
performance, loss of trailer
brakes, or other malfunctions, and
could cause a crash. You or
others could be injured or killed.
Before using one of these
devices:
.
Ask the device or trailer
manufacturer if the device
has been thoroughly tested
for compatibility with the
make, model, and year of
the vehicle as well as
optional equipment installed
on the vehicle.
.
Before driving on the open
roads, check that the trailer
brakes are working properly.
Drive the vehicle with the
trailer attached on a level
road surface that is free of
traffic at about 32-40 km/h
(20-25 mph) and fully apply
(Continued) Warning (Continued) the manual trailer brake
apply lever. Also check that
the trailer brake lamps and
other lamps are functioning
correctly.
.
If the trailer brakes are not
operating properly at any
time, or if a DIC message
indicates problems with the
trailer connections or trailer
brakes, carefully pull the
vehicle over to the side of
the road when traffic
conditions allow. Conversions and
Add-Ons Add-On Electrical
Equipment
{ WarningThe Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/
Maintenance testing. See
Malfunction Indicator Lamp
(Check Engine Light) 0 143 .
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle
systems. This could affect vehicle
operation and cause a crash.
Such devices may also access
information stored in the vehicle ’ s
systems.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
276 Vehicle Care
Vehicle Care General Information General Information . . . . . . . . . . 277
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 277
California Perchlorate
Materials Requirements . . . . . 278
Accessories and
Modifications . . . . . . . . . . . . . . . . 278
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 278
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 279
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 280
Engine Oil . . . . . . . . . . . . . . . . . . . . 283
Engine Oil Life System . . . . . . . 285
Automatic Transmission Fluid
(6 Speed Transmission) . . . . . 286
Automatic Transmission Fluid
(8 and 10 Speed
Transmission) . . . . . . . . . . . . . . . 289
Engine Air Cleaner/Filter . . . . . . 290
Cooling System . . . . . . . . . . . . . . 291
Engine Overheating . . . . . . . . . . 294
Engine Fan . . . . . . . . . . . . . . . . . . . 296
Washer Fluid . . . . . . . . . . . . . . . . . 296
Brakes . . . . . . . . . . . . . . . . . . . . . . . 297 Brake Fluid . . . . . . . . . . . . . . . . . . . 297
Battery - North America . . . . . . 298
Four-Wheel Drive . . . . . . . . . . . . . 299
Front Axle . . . . . . . . . . . . . . . . . . . . 300
Rear Axle . . . . . . . . . . . . . . . . . . . . 300
Noise Control System . . . . . . . . 301
Starter Switch Check . . . . . . . . . 302
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 302
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 303
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 303
Wiper Blade Replacement . . . . 303
Glass Replacement . . . . . . . . . . 304
Windshield Replacement . . . . . 304
Gas Strut(s) . . . . . . . . . . . . . . . . . . 305
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 306
Bulb Replacement Bulb Replacement . . . . . . . . . . . . 306
High Intensity Discharge (HID)
Lighting . . . . . . . . . . . . . . . . . . . . . 306
LED Lighting . . . . . . . . . . . . . . . . . 307
Fog Lamps . . . . . . . . . . . . . . . . . . . 307
Back-Up Lamps . . . . . . . . . . . . . . 307
License Plate Lamp . . . . . . . . . . 308 Electrical System Electrical System Overload . . . 309
Fuses and Circuit Breakers . . . 309
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 310
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 314
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 317
Rear Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 319
Wheels and Tires Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 320
All-Season Tires . . . . . . . . . . . . . . 321
Winter Tires . . . . . . . . . . . . . . . . . . 321
Low-Profile Tires . . . . . . . . . . . . . 322
All-Terrain Tires . . . . . . . . . . . . . . . 322
Tire Sidewall Labeling . . . . . . . . 322
Tire Designations . . . . . . . . . . . . . 324
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 324
Tire Pressure . . . . . . . . . . . . . . . . . 327
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 328
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 329
Tire Pressure Monitor
Operation . . . . . . . . . . . . . . . . . . . 330
Tire Inspection . . . . . . . . . . . . . . . . 333
Tire Rotation . . . . . . . . . . . . . . . . . 334

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 277When It Is Time for New
Tires . . . . . . . . . . . . . . . . . . . . . . . . 335
Buying New Tires . . . . . . . . . . . . . 335
Different Size Tires and
Wheels . . . . . . . . . . . . . . . . . . . . . . 337
Uniform Tire Quality
Grading . . . . . . . . . . . . . . . . . . . . . 337
Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . . . 339
Wheel Replacement . . . . . . . . . . 339
Tire Chains . . . . . . . . . . . . . . . . . . . 340
If a Tire Goes Flat . . . . . . . . . . . . 341
Tire Changing . . . . . . . . . . . . . . . . 342
Full-Size Spare Tire . . . . . . . . . . 350
Jump Starting Jump Starting - North
America . . . . . . . . . . . . . . . . . . . . . 351
Towing the Vehicle Towing the Vehicle . . . . . . . . . . . 355
Recreational Vehicle
Towing . . . . . . . . . . . . . . . . . . . . . . 355
Appearance Care Exterior Care . . . . . . . . . . . . . . . . . 360
Interior Care . . . . . . . . . . . . . . . . . . 364
Floor Mats . . . . . . . . . . . . . . . . . . . . 367 General Information For service and parts needs, visit
your dealer. You will receive
genuine GM parts and GM-trained
and supported service people.
Genuine GM parts have one of
these marks:
California Proposition
65 Warning
{ WarningMost motor vehicles, including
this one, as well as many of its
service parts and fluids, contain
and/or emit chemicals known to
the State of California to cause
cancer and birth defects or other
reproductive harm. Engine
exhaust, many parts and
systems, many fluids, and some
component wear by-products
contain and/or emit these
chemicals. For more information
go to www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0 298
and Jump Starting - North America
0 351 and the back cover.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
278 Vehicle Care
California Perchlorate
Materials Requirements Certain types of automotive
applications, such as airbag
initiators, seat belt pretensioners,
and lithium batteries contained in
Remote Keyless Entry transmitters,
may contain perchlorate materials.
Special handling may be necessary.
For additional information, see
www.dtsc.ca.gov/hazardouswaste/
perchlorate.
Accessories and
Modifications Adding non-dealer accessories or
making modifications to the vehicle
can affect vehicle performance and
safety, including such things as
airbags, braking, stability, ride and
handling, emissions systems,
aerodynamics, durability, and
electronic systems like antilock
brakes, traction control, and stability
control. These accessories or
modifications could even cause
malfunction or damage not covered
by the vehicle warranty. Damage to suspension components
caused by modifying vehicle height
outside of factory settings will not be
covered by the vehicle warranty.
Damage to vehicle components
resulting from modifications or the
installation or use of non-GM
certified parts, including control
module or software modifications, is
not covered under the terms of the
vehicle warranty and may affect
remaining warranty coverage for
affected parts.
GM Accessories are designed to
complement and function with other
systems on the vehicle. See your
dealer to accessorize the vehicle
using genuine GM Accessories
installed by a dealer technician.
Also, see Adding Equipment to the
Airbag-Equipped Vehicle 0 95 .Vehicle Checks Doing Your Own
Service Work
{ WarningIt can be dangerous to work on
your vehicle if you do not have
the proper knowledge, service
manual, tools, or parts. Always
follow owner ’ s manual procedures
and consult the service manual
for your vehicle before doing any
service work.
If doing some of your own service
work, use the proper service
manual. It tells you much more
about how to service the vehicle
than this manual can. To order the
proper service manual, see Service
Publications Ordering Information
0 395 .
This vehicle has an airbag system.
Before attempting to do your own
service work, see Servicing the
Airbag-Equipped Vehicle 0 95 .

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 2831. Positive (+) Terminal. See
Jump Starting - North America
0 351 .
2. Battery - North America 0 298 .
3. Coolant Surge Tank and
Pressure Cap. See Cooling
System 0 291 .
4. Engine Air Cleaner/Filter 0 290 .
5. Remote Negative ( – ) Location
(Out of View). See Jump
Starting - North America 0 351 .
6. Engine Cooling Fans (Out of
View). See Cooling System
0 291 .
7. Engine Oil Fill Cap. See “ When
to Add Engine Oil ” under
Engine Oil 0 283 .
8. Engine Oil Dipstick. See
“ Checking Engine Oil ” under
Engine Oil 0 283 .
9. Windshield Washer Fluid
Reservoir. See “ Adding Washer
Fluid ” under Washer Fluid
0 296 .
10. Brake Fluid Reservoir. See
Brake Fluid 0 297 . 11. Engine Compartment Fuse
Block 0 310 .
Engine Oil To ensure proper engine
performance and long life, careful
attention must be paid to engine oil.
Following these simple, but
important steps will help protect
your investment:
.
Use engine oil approved to the
proper specification and of the
proper viscosity grade. See
“ Selecting the Right Engine Oil ”
in this section.
.
Check the engine oil level
regularly and maintain the
proper oil level. See “ Checking
Engine Oil ” and “ When to Add
Engine Oil ” in this section.
.
Change the engine oil at the
appropriate time. See Engine Oil
Life System 0 285 .
.
Always dispose of engine oil
properly. See “ What to Do with
Used Oil ” in this section. Checking Engine Oil If equipped, the ENGINE OIL LOW
ADD OIL message displays when
the engine oil level may be too low.
Check the oil level before filling to
the recommended level. If the oil is
not low and this message remains
on, see your dealer.
Check the engine oil level regularly,
every 650 km (400 mi), especially
prior to a long trip. The engine oil
dipstick handle is a loop. See
Engine Compartment Overview
0 280 for the location.
{ WarningThe engine oil dipstick handle
may be hot; it could burn you.
Use a towel or glove to touch the
dipstick handle.
Follow these guidelines:
.
To get an accurate reading, park
the vehicle on level ground.
Check the engine oil level after
the engine has been off for at
least two hours. Checking the

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 285Engine oils that have been
approved by GM as meeting the
dexos1 specification are marked
with the dexos1 approved logo. See
www.gmdexos.com.
CautionFailure to use the recommended
engine oil or equivalent can result
in engine damage not covered by
the vehicle warranty.
Viscosity Grade
Use SAE 0W-20 viscosity grade
engine oil.
When selecting an oil of the
appropriate viscosity grade, it is
recommended to select an oil of the
correct specification. See
“ Specification ” earlier in this section. Engine Oil Additives/Engine
Oil Flushes Do not add anything to the oil. The
recommended oils meeting the
dexos1 specification are all that is
needed for good performance and
engine protection.
Engine oil system flushes are not
recommended and could cause
engine damage not covered by the
vehicle warranty.
What to Do with Used Oil Used engine oil contains certain
elements that can be unhealthy for
your skin and could even cause
cancer. Do not let used oil stay on
your skin for very long. Clean your
skin and nails with soap and water,
or a good hand cleaner. Wash or
properly dispose of clothing or rags
containing used engine oil. See the
manufacturer's warnings about the
use and disposal of oil products.
Used oil can be a threat to the
environment. If you change your
own oil, be sure to drain all the oil
from the filter before disposal. Never
dispose of oil by putting it in the trash or pouring it on the ground,
into sewers, or into streams or
bodies of water. Recycle it by taking
it to a place that collects used oil.
Engine Oil Life System When to Change Engine Oil This vehicle has a computer system
that indicates when to change the
engine oil and filter. This is based
on a combination of factors which
include engine revolutions, engine
temperature, and miles driven.
Based on driving conditions, the
mileage at which an oil change is
indicated can vary considerably. For
the oil life system to work properly,
the system must be reset every time
the oil is changed.
When the system has calculated
that oil life has been diminished, a
CHANGE ENGINE OIL SOON
message comes on to indicate that
an oil change is necessary. Change
the oil as soon as possible within
the next 1 000 km (600 mi). It is
possible that, if driving under the
best conditions, the oil life system
may indicate that an oil change is

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 291
{ WarningOperating the engine with the air
cleaner/filter off can cause you or
others to be burned. The air
cleaner not only cleans the air; it
helps to stop flames if the engine
backfires. Use caution when
working on the engine and do not
drive with the air cleaner/filter off.
CautionIf the air cleaner/filter is off, dirt
can easily get into the engine,
which could damage it. Always
have the air cleaner/filter in place
when driving.
Cooling System The cooling system allows the
engine to maintain the correct
working temperature. 1. Coolant Surge Tank
2. Coolant Surge Tank
Pressure Cap
3. Engine Electric
Cooling Fan(s)
{ Warning
An underhood electric fan can
start up even when the engine is
not running and can cause injury.
Keep hands, clothing, and tools
away from any underhood
electric fan. { WarningDo not touch heater or radiator
hoses, or other engine parts.
They can be very hot and can
burn you. Do not run the engine if
there is a leak; all coolant could
leak out. That could cause an
engine fire and can burn you. Fix
any leak before driving the
vehicle.
Engine Coolant The cooling system in the vehicle is
filled with DEX-COOL engine
coolant. This coolant is designed to
remain in the vehicle for 5 years or
240 000 km (150,000 mi), whichever
occurs first.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating 0 294 .

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
292 Vehicle Care What to Use
{ WarningPlain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
warning. The engine could catch
fire and you or others could be
burned.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. This mixture:
.
Gives freezing protection down
to − 37 °C ( − 34 °F), outside
temperature
.
Gives boiling protection up to
129 °C (265 °F), engine
temperature
.
Protects against rust and
corrosion
.
Will not damage aluminum parts .
Helps keep the proper engine
temperature
CautionDo not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard
GMW3420 and clean, drinkable
water. Anything else can cause
damage to the engine cooling
system and the vehicle, which
would not be covered by the
vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, or by pouring
it on the ground, or into sewers,
streams, or bodies of water. Have
the coolant changed by an
authorized service center, familiar
with legal requirements regarding
used coolant disposal. This will help
protect the environment and your
health. Checking Coolant The coolant surge tank is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview
0 280 .
The vehicle must be on a level
surface when checking the coolant
level.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, wait until it cools down. The
coolant level should be at or above

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
Vehicle Care 293the full cold mark. If it is not, there
may be a leak in the cooling
system.
If coolant is visible but the coolant
level is not at or above the full cold
mark, see “ How to Add Coolant to
the Coolant Surge Tank, ” following.
How to Add Coolant to the
Coolant Surge Tank
{ WarningSpilling coolant on hot engine
parts can burn you. Coolant
contains ethylene glycol and it will
burn if the engine parts are hot
enough.
{ Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
(Continued) Warning (Continued) warning. The engine could catch
fire and you or others could be
burned.
{ WarningSteam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to cool.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
(Continued) Caution (Continued) cause system damage. If coolant
is not visible in the surge tank,
contact your dealer.
If no coolant is visible in the surge
tank, add coolant.
1. Remove the coolant surge tank
pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot.
Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means
there is still some pressure left.
2. Keep turning the pressure cap
slowly, and remove it.

GMC Yukon/Yukon XL/Denali Owner Manual (GMNA-Localizing-U.S./
Canada/Mexico-11349262) - 2018 - crc - 6/20/17
294 Vehicle Care 3. Fill the coolant surge tank with
the proper mixture to the full
cold mark.
4. With the coolant surge tank
pressure cap off, start the
engine and let it run until the
engine coolant temperature
gauge indicates approximately
90 °C (195 °F).
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge
tank until the level reaches the
full cold mark.
5. Replace the pressure cap
tightly.
6. Verify coolant level after the
engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1 – 6. CautionIf the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the
cap is properly and tightly
secured.
Engine Overheating CautionDo not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all
coolant and can damage the
system and vehicle. Have any
leaks fixed right away.
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge in the vehicle's instrument
cluster. See Engine Coolant
Temperature Gauge 0 138 . In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program
0 390 .
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
Check to see if the engine cooling
fan(s) are running. If the engine is
overheating, the fans should be
running. If they are not, do not
continue to run the engine. Have the
vehicle serviced.