service GMC SIERRA 2019 Repair Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
310 Driving and Operating
Settings View
Within the Trailering App, touch the
Settings tab to modify the following
settings:
.Trailer Detection Alert
. Maintenance Alerts
. Security Alert
. Tow/Haul Mode Reminder
Trailer Detection Alert
The Trailer Detection Alert setting
will be on by default. Turn it off to
disable the Trailer Detection pop-up
from displaying when a trailer is
connected. The Guest Trailer Profile
will become the active Trailer
Profile, unless another Trailer Profile
is selected manually through the
Trailering App. If this setting is
disabled while a Custom Trailer
Profile is active, that Trailer Profile
will remain the active profile until the
trailer is disconnected.
Maintenance Alerts
Touch Maintenance Alerts to view
the Maintenance Alerts settings
page. These alerts are based on the
Trailer Profile, so the settings for
each Trailer Profile must be turned
on or off. Touch a profile to view
more information or adjust the
setting for that profile.
The setting will be on by default for
each profile. All Maintenance Alerts
for that active Trailer Profile will be
received.
Turn a setting off to not receive any
of the Maintenance Alerts when that
Trailer Profile is active.
Security Alert
A security alert can be set if a trailer
is connected and the alert is
enabled. When the trailer is
disconnected and the vehicle is off,
an alarm will sound. Touch Security Alert in Settings to
view the Security Alert settings
page. These alerts are based on the
Trailer Profile, so the settings for
each Trailer Profile must be turned
on or off. Touch a profile to view
more information or adjust the
setting for that profile.
This setting will be off by default for
each Trailer Profile, including the
Guest Trailer Profile.
A smartphone will receive a
notification that the trailer related to
the selected Trailer Profile is
disconnected from the vehicle, if the
setting is on for the active Trailer
Profile, the vehicle has an OnStar or
connected service plan and the
smartphone number has been
added to the account for this
notification.
If the setting is turned off for a given
Trailer Profile, the smartphone will
not receive this security notification
even if the Trailer Profile is active.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Driving and Operating 311
Tow/Haul Mode Reminder
This is a reminder to turn on the
Tow/Haul Mode when towing a
trailer. SeeTow/Haul Mode 0238.
Touch Tow/Haul Mode Reminder in
Settings to view the Tow/Haul Mode
Reminder settings page. These
alerts are based on the Trailer
Profile, so the settings for each
Trailer Profile must be turned on or
off. Touch a profile to view more
information or to adjust the setting
for that profile.
This setting will default to OFF for
each Trailer Profile, including the
Guest Trailer Profile.
If Tow/Haul Mode is off and this
setting is on for a Trailer Profile,
each time the ignition is turned on a
reminder will appear to turn on Tow/
Haul Mode when the Trailer Profile
is active.
If Tow/Haul Mode is on and this
setting is on for a Trailer Profile, the
reminder will not appear when the
Trailer Profile is active.
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. See Malfunction
Indicator Lamp (Check Engine
Light) 0151. 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.
Caution
Some electrical equipment can
damage the vehicle or cause
components to not work and
would not be covered by the
vehicle warranty. Always check
with your dealer before adding
electrical equipment.
Add-on equipment can drain the
vehicle's 12-volt battery, even if the
vehicle is not operating.
The vehicle has an airbag system.
Before attempting to add anything
electrical to the vehicle, see
Servicing the Airbag-Equipped
Vehicle 097 and
Adding Equipment to the
Airbag-Equipped Vehicle 098.
For information on wiring auxiliary
switches, see www.gmupfitter.com
or contact your dealer.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
316 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 317
California Proposition65 Warning . . . . . . . . . . . . . . . . . 318
California Perchlorate Materials Requirements . . . . . 318
Accessories and Modifications . . . . . . . . . . . . . . . . 318
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 319
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 319
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 321
Engine Oil . . . . . . . . . . . . . . . . . . . . 326
Engine Oil Life System . . . . . . . 328
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 330
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 330
Engine Air Cleaner/Filter . . . . . . 331
Cooling System . . . . . . . . . . . . . . 332
Engine Overheating . . . . . . . . . . 336
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 338
Engine Fan . . . . . . . . . . . . . . . . . . . 338 Washer Fluid . . . . . . . . . . . . . . . . . 339
Brakes . . . . . . . . . . . . . . . . . . . . . . . 340
Brake Pad Life System . . . . . . . 340
Brake Fluid . . . . . . . . . . . . . . . . . . . 341
Battery - North America . . . . . . 342
Four-Wheel Drive . . . . . . . . . . . . . 345
Front Axle . . . . . . . . . . . . . . . . . . . . 345
Rear Axle . . . . . . . . . . . . . . . . . . . . 346
Noise Control System . . . . . . . . 347
Starter Switch Check . . . . . . . . . 348
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 348
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 348
Wiper Blade Replacement . . . . 349
Windshield Replacement . . . . . 350
Gas Strut(s) . . . . . . . . . . . . . . . . . . 350
Headlamp Aiming
Front Headlamp Aiming . . . . . . 351
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 351
Halogen Bulbs . . . . . . . . . . . . . . . . 351
LED Lighting . . . . . . . . . . . . . . . . . 352
Headlamps, Front Turn Signal, Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 352
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 352 Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 353
License Plate Lamp . . . . . . . . . . 354
Electrical System
Electrical System Overload . . . 354
Fuses and Circuit Breakers . . . 355
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 355
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 359
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 361
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 363
All-Season Tires . . . . . . . . . . . . . . 364
Winter Tires . . . . . . . . . . . . . . . . . . 364
Low-Profile Tires . . . . . . . . . . . . . 365
All-Terrain Tires . . . . . . . . . . . . . . . 365
Tire Sidewall Labeling . . . . . . . . 365
Tire Designations . . . . . . . . . . . . . 368
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 369
Tire Pressure . . . . . . . . . . . . . . . . . 372
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 373
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 374

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 317
Tire Pressure MonitorOperation . . . . . . . . . . . . . . . . . . . 375
Tire Inspection . . . . . . . . . . . . . . . . 380
Tire Rotation . . . . . . . . . . . . . . . . . 381
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 382
Buying New Tires . . . . . . . . . . . . . 383
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 384
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 385
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 386
Wheel Replacement . . . . . . . . . . 386
Tire Chains . . . . . . . . . . . . . . . . . . . 387
If a Tire Goes Flat . . . . . . . . . . . . 388
Tire Changing . . . . . . . . . . . . . . . . 390
Full-Size Spare Tire . . . . . . . . . . 399
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . 400
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . 403
Recreational VehicleTowing . . . . . . . . . . . . . . . . . . . . . . 404
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . 408
Interior Care . . . . . . . . . . . . . . . . . . 413
Floor Mats . . . . . . . . . . . . . . . . . . . . 416
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:

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
318 Vehicle Care
California Proposition
65 Warning
{Warning
Most 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 0342
and
Jump Starting - North America
0 400 and the back cover.
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 098.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 319
Vehicle Checks
Doing Your Own
Service Work
{Warning
It 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
Publication Ordering Information
0 447.
This vehicle has an airbag system.
Before attempting to do your own
service work, see Servicing the
Airbag-Equipped Vehicle 097. If equipped with remote vehicle
start, open the hood before
performing any service work to
prevent remote starting the vehicle
accidentally. See
Remote Vehicle
Start 044.
Keep a record with all parts receipts
and list the mileage and the date of
any service work performed. See
Maintenance Records 0433.
Caution
Even small amounts of
contamination can cause damage
to vehicle systems. Do not allow
contaminants to contact the fluids,
reservoir caps, or dipsticks.
Hood
{Warning
Turn the vehicle off before
opening the hood. If the vehicle is
on, the engine will start when the
hood is opened. You or others
could be injured.
{Warning
Components under the hood can
get hot from running the engine.
To help avoid the risk of burning
unprotected skin, never touch
these components until they have
cooled, and always use a glove or
towel to avoid direct skin contact.
Clear any snow from the hood
before opening.
To open the hood: 1. Pull the hood release lever with the
isymbol. It is on the
lower left side of the instrument
panel.
2. Go to the front of the vehicle and locate the secondary
release lever under the front
center of the hood. Push the
secondary hood release lever
to the right to release.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 327
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
engine oil level on steep grades
or too soon after engine shutoff
can result in incorrect readings.
Accuracy improves when
checking a cold engine prior to
starting. Remove the dipstick
and check the level.
. If unable to wait two hours, the
engine must be off for at least
15 minutes if the engine is
warm, or at least 30 minutes if
the engine is not warm. Pull out
the dipstick, wipe it with a clean
paper towel or cloth, then push it
back in all the way. Remove it
again, keeping the tip down, and
check the level.When to Add Engine Oil
If the oil is below the cross-hatched
area at the tip of the dipstick and
the engine has been off for at least
15 minutes, add 1 L (1 qt) of the
recommended oil and then recheck
the level. See “Selecting the Right
Engine Oil” later in this section for
an explanation of what kind of oil to
use. For engine oil crankcase
capacity, see Capacities and
Specifications 0435.
Caution
Do not add too much oil. Oil
levels above or below the
acceptable operating range
shown on the dipstick are harmful
to the engine. If the oil level is
(Continued)
Caution (Continued)
above the operating range (i.e.,
the engine has so much oil that
the oil level gets above the
cross-hatched area that shows
the proper operating range), the
engine could be damaged. Drain
the excess oil or limit driving of
the vehicle, and seek a service
professional to remove the
excess oil.
See Engine Compartment Overview
0 321 for the location of the engine
oil fill cap.
Add enough oil to put the level
somewhere in the proper operating
range. Push the dipstick all the way
back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil
depends on both the proper oil
specification and viscosity grade.
See Recommended Fluids and
Lubricants 0430.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 329
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.
On some vehicles, 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 might indicate that an oil
change is not necessary for up to a
year. The engine oil and filter must
be changed at least once a year
and, at this time, the system must
be reset. For vehicles without the
CHANGE ENGINE OIL SOON
message, an oil change is needed
when the REMAINING OIL LIFE
percentage is near 0%. Your dealer
has trained service people who will
perform this work and reset the
system. It is also important to checkthe oil regularly over the course of
an oil drain interval and keep it at
the proper level.
If the system is ever reset
accidentally, the oil must be
changed at 5 000 km (3,000 mi)
since the last oil change.
Remember to reset the oil life
system whenever the oil is changed.
How to Reset the Engine Oil
Life System
Reset the system whenever the
engine oil is changed so that the
system can calculate the next
engine oil change. Always reset the
engine oil life to 100% after every oil
change. It will not reset itself. To
reset the engine oil life system:
1. Display the oil life percentage on the DIC. See Driver
Information Center (DIC)
(Midlevel and Uplevel) 0163 or
Driver Information Center (DIC)
(Base Level) 0161.
2. Press the thumbwheel on the steering wheel, or the trip
odometer reset stem if the
vehicle does not have DIC controls, for several seconds.
When the confirmation
message displays, select YES.
The oil life will change
to 100%.
The oil life system can also be reset
as follows:
1. Display the oil life percentage on the DIC. See Driver
Information Center (DIC)
(Midlevel and Uplevel) 0163 or
Driver Information Center (DIC)
(Base Level) 0161.
2. Fully press the accelerator pedal slowly three times within
five seconds.
3. If the display changes to 100%, the system is reset.
If the vehicle has a CHANGE
ENGINE OIL SOON message and it
comes back on when the vehicle is
started and/or the oil life percentage
is near 0%, the engine oil life
system has not been reset. Repeat
the procedure.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
330 Vehicle Care
Automatic Transmission
Fluid
When to Check and Change
Automatic Transmission Fluid
It is usually not necessary to check
the transmission fluid level. The only
reason for fluid loss is a
transmission leak or overheated
transmission. This vehicle is not
equipped with a transmission fluid
level dipstick. There is a special
procedure for checking and
changing the transmission fluid in
these vehicles. Because this
procedure is difficult, this should be
done at the dealer. Contact the
dealer for additional information or
the procedure can be found in the
service manual. SeePublication
Ordering Information 0447.
Caution
Use of the incorrect automatic
transmission fluid may damage
the vehicle, and the damage may
(Continued)
Caution (Continued)
not be covered by the vehicle
warranty. Always use the correct
automatic transmission fluid. See
Recommended Fluids and
Lubricants0430.
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule
0 420. Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0430.
Engine Air Filter Life
System
If equipped, this feature provides
the engine air filter ’s remaining life
and best timing for a change. The
timing to change an engine air filter
depends on driving and
environmental conditions.
When to Change the Engine
Air Filter
When the Driver Information Center
(DIC) displays a message to replace
the engine air filter at the next oil
change, follow this timing.
When the DIC displays a message
to replace the engine air filter soon,
replace the engine air filter at the
earliest convenience.
The system must be reset after the
engine air filter is changed.
If the DIC displays a message to
check the engine air filter system,
see your dealer.
How to Reset the Engine Air
Filter Life System
To reset:
1. Place the vehicle in P (Park).
2. Display the Air Filter Life on the DIC. See Driver Information
Center (DIC) (Midlevel and
Uplevel) 0163 or
Driver Information Center (DIC)
(Base Level) 0161.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
334 Vehicle Care
.Helps keep the proper engine
temperature.
Caution
Do 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 driver
side of the vehicle. See Engine
Compartment Overview 0321.
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 the indicated 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 indicated
mark, see the following sections on
how to add coolant to the coolant
surge tank.
Automatic Coolant Service Fill
Instructions (L3B Engine)
See 3.0L Duramax Diesel
supplement for the diesel engine
procedure.
If equipped, this feature assists in
filling and removing air from the
cooling system after service of
components or when coolant is
added after being too low.
To activate the fill and air removal
process:
1. With a cold system, add coolant to the indicated mark
on the surge tank.
2. Replace the cap on the surge tank.