
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Keys, Doors, and Windows 13
Press the button to remove the key.
Never pull the key out without
pressing the button.
See your dealer if a replacement
key or additional key is needed.
If it becomes difficult to turn a key,
inspect the key blade for debris.
Periodically clean with a brush
or pick.
With an active OnStar or connected
service plan, an OnStar Advisor
may remotely unlock the vehicle.
SeeOnStar Overview 0476.
If locked out of the vehicle, see
Roadside Assistance Program
0 466. If equipped with memory seats, RKE
transmitters 1 and 2 are linked to
seating positions of memory 1 or 2.
See
Memory Seats 058.
Remote Keyless Entry
(RKE) System
See Radio Frequency Statement
0 472.
If there is a decrease in the Remote
Keyless Entry (RKE) operating
range:
. Check the distance. The
transmitter may be too far from
the vehicle.
. Check the location. Other
vehicles or objects may be
blocking the signal.
. Check the transmitter's battery.
See “Battery Replacement” later
in this section.
. If the transmitter is still not
working correctly, see your
dealer or a qualified technician
for service.
Remote Keyless Entry
(RKE) System Operation
(Key Access)
The RKE transmitter functions may
work up to 60 m (197 ft) away from
the vehicle.
Other conditions can affect the
performance of the transmitter. See
Remote Keyless Entry (RKE)
System 013.
/:Press and releaseQ, then
immediately press and hold
/until
the turn signal lamps flash or for at

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Keys, Doors, and Windows 15
Battery Replacement
{Warning
Never allow children to play with
the RKE transmitter. The
transmitter contains a small
battery, which can be a choking
hazard. If swallowed, internal
burns can occur, resulting in
severe injury or death. Seek
medical attention immediately if a
battery is swallowed.
{Warning
To avoid personal injury, do not
touch metal surfaces on the RKE
transmitter when it has been
exposed to extreme heat. These
surfaces can be hot to the touch
at temperatures above 59 °C
(138 °F).
Caution
When replacing the battery, do
not touch any of the circuitry on
the transmitter. Static from your
body could damage the
transmitter.
Caution
Always replace the battery with
the correct type. Replacing the
battery with an incorrect type
could potentially create a risk of
battery explosion. Dispose of
used batteries according to
instructions and local laws. Do
not attempt to burn, crush, or cut
the used battery, and avoid
exposing the battery to
environments with extremely low
air pressures or high
temperatures.Replace the battery in the
transmitter soon if the REPLACE
BATTERY IN REMOTE KEY
displays in the Driver Information
Center (DIC).
To replace the battery:
1. Separate and remove the back
cover of the transmitter with a
flat, thin object, such as a coin.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
20 Keys, Doors, and Windows
times after all doors are closed. To
turn on or off seeVehicle
Personalization 0156.
Remote No Longer in Vehicle Alert
If the vehicle is on with a door open
and then all doors are closed, the
vehicle will check for RKE
transmitters inside. If an RKE
transmitter is not detected, the
Driver Information Center (DIC) will
display NO REMOTE DETECTED
and the horn will chirp three times.
This occurs only once each time the
vehicle is driven. To turn on or off
see Vehicle Personalization 0156.
Key Access
To access a vehicle with a dead
transmitter battery, see Door Locks
0 26.
Programming Transmitters to
the Vehicle
Only RKE transmitters programmed
to the vehicle will work. If a
transmitter is lost or stolen, a
replacement can be purchased and
programmed through your dealer.
The vehicle can be reprogrammed so that lost or stolen transmitters no
longer work. Each vehicle can have
up to eight transmitters matched
to it.
Programming with Recognized
Transmitters
A new transmitter can be
programmed to the vehicle when
there are two recognized
transmitters.
To program, the vehicle must be off
and all transmitters, both currently
recognized and new, must be
with you.
1. Remove the key from a recognized transmitter.
2. Place the two recognized transmitters in the cupholder or
on the passenger seat.
3. Insert the vehicle key into the key lock cylinder on the driver
door handle. Then turn the key
counterclockwise, to the unlock
position, five times within
10 seconds.
The DIC displays READY FOR
REMOTE#3, 4, 5 ETC.
Transmitter Pocket without Bucket
Seats (Lower Compartment)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Keys, Doors, and Windows 23
To start the vehicle:
Transmitter Pocket without BucketSeats (Lower Compartment)
Transmitter Pocket with Bucket Seats
1. Place the transmitter in the transmitter pocket/insert.
2. With the vehicle in P (Park) or N (Neutral) press the brake
pedal and ENGINE
START/STOP.
Replace the transmitter battery
as soon as possible.
Battery Replacement
{Warning
Never allow children to play with
the RKE transmitter. The
transmitter contains a small
battery, which can be a choking
hazard. If swallowed, internal
burns can occur, resulting in
severe injury or death. Seek
medical attention immediately if a
battery is swallowed.
{Warning
To avoid personal injury, do not
touch metal surfaces on the RKE
transmitter when it has been
exposed to extreme heat. These
surfaces can be hot to the touch
at temperatures above 59 °C
(138 °F).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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82 Seats and Restraints
Warning (Continued)
seatback may interfere with the
proper operation of the passenger
sensing system.
Servicing the
Airbag-Equipped Vehicle
Airbags affect how the vehicle
should be serviced. There are parts
of the airbag system in several
places around the vehicle. Your
dealer and the service manual have
information about servicing the
vehicle and the airbag system. To
purchase a service manual, see
Publication Ordering Information
0471.
{Warning
For up to 10 seconds after the
vehicle is turned off and the
battery is disconnected, an airbag
can still inflate during improper
service. You can be injured if you
(Continued)
Warning (Continued)
are close to an airbag when it
inflates. Avoid yellow connectors.
They are probably part of the
airbag system. Be sure to follow
proper service procedures, and
make sure the person performing
work for you is qualified to do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Adding accessories that change the
vehicle's frame, bumper system,
height, front end, or side sheet
metal, may keep the airbag system
from working properly.
The operation of the airbag system
can also be affected by changing,
including improperly repairing or
replacing, any parts of the following:
.Airbag system, including airbag
modules, front or side impact
sensors, sensing and diagnostic
module, or airbag wiring .
Front seats, including stitching,
seams, or zippers
. Seat belts
. Steering wheel, instrument
panel, overhead console, ceiling
trim, or pillar garnish trim
. Inner door seals, including
speakers
Your dealer and the service manual
have information about the location
of the airbag modules and sensors,
sensing and diagnostic module, and
airbag wiring along with the proper
replacement procedures.
In addition, the vehicle has a
passenger sensing system for the
front outboard passenger position,
which includes sensors that are part
of the passenger seat. The
passenger sensing system may not
operate properly if the original seat
trim is replaced with non-GM
covers, upholstery, or trim; or with
GM covers, upholstery, or trim
designed for a different vehicle. Any
object, such as an aftermarket seat
heater or a comfort-enhancing pad
or device, installed under or on top

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Instruments and Controls 155
Clean the HUD lens with a soft cloth
sprayed with glass cleaner. Wipe
the lens gently, then dry it.
HUD Troubleshooting
Check that:
.Nothing is covering the
HUD lens.
. The HUD brightness setting is
not too dim or too bright.
. The HUD is adjusted to the
proper height.
. Polarized sunglasses are
not worn.
. The windshield and HUD lens
are clean.
If the HUD image is not correct,
contact your dealer.
The windshield is part of the HUD
system. See Windshield
Replacement 0365.
Vehicle Messages
Messages displayed on the Driver
Information Center (DIC) indicate
the status of the vehicle or some
action that may be needed to
correct a condition. Multiple
messages may appear one after
another.
The messages that do not require
immediate action can be
acknowledged and cleared by
pressing the thumbwheel. The
messages that require immediate
action cannot be cleared until that
action is performed.
All messages should be taken
seriously; clearing the message
does not correct the problem.
If a SERVICE message appears,
see your dealer.
Follow the instructions given in the
messages. The system displays
messages regarding the following
topics:
.
Service Messages
. Fluid Levels .
Vehicle Security
. Brakes
. Steering
. 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. A reduction in propulsion
power can affect the vehicle's ability
to accelerate. If this message is on,
but there is no observed reduction

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 327
Vehicle Care
General Information
General Information . . . . . . . . . . 328
California Proposition65 Warning . . . . . . . . . . . . . . . . . 329
California Perchlorate Materials Requirements . . . . . 329
Accessories and Modifications . . . . . . . . . . . . . . . . 329
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 330
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 330
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 332
Engine Oil . . . . . . . . . . . . . . . . . . . . 339
Engine Oil Life System . . . . . . . 341
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 343
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 343
Engine Air Cleaner/Filter . . . . . . 344
Cooling System . . . . . . . . . . . . . . 346
Engine Overheating . . . . . . . . . . 351
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 352
Engine Fan . . . . . . . . . . . . . . . . . . . 353 Power Steering Fluid . . . . . . . . . 354
Washer Fluid . . . . . . . . . . . . . . . . . 354
Brakes . . . . . . . . . . . . . . . . . . . . . . . 355
Brake Pad Life System . . . . . . . 356
Brake Fluid . . . . . . . . . . . . . . . . . . . 357
Battery - North America . . . . . . 358
Four-Wheel Drive . . . . . . . . . . . . . 361
Front Axle . . . . . . . . . . . . . . . . . . . . 361
Rear Axle . . . . . . . . . . . . . . . . . . . . 362
Noise Control System . . . . . . . . 362
Starter Switch Check . . . . . . . . . 363
Automatic Transmission Shift
Lock Control Function
Check . . . . . . . . . . . . . . . . . . . . . . . 363
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . . 363
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 364
Wiper Blade Replacement . . . . 364
Windshield Replacement . . . . . 365
Gas Strut(s) . . . . . . . . . . . . . . . . . . 365
Headlamp Aiming
Front Headlamp Aiming . . . . . . 366
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 367
Halogen Bulbs . . . . . . . . . . . . . . . . 367
LED Lighting . . . . . . . . . . . . . . . . . 367 Headlamps, Front Turn Signal,
Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 367
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 368
Center High-Mounted Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 369
License Plate Lamp . . . . . . . . . . 369
Electrical System
Electrical System Overload . . . 370
Fuses and Circuit Breakers . . . 370
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 371
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 374
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 376
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 379
All-Season Tires . . . . . . . . . . . . . . 379
Winter Tires . . . . . . . . . . . . . . . . . . 380
Low-Profile Tires . . . . . . . . . . . . . 380
All-Terrain Tires . . . . . . . . . . . . . . . 381
Tire Sidewall Labeling . . . . . . . . 381
Tire Designations . . . . . . . . . . . . . 383
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 385

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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358 Vehicle Care
{Warning
If too much brake fluid is added, it
can spill on the engine and burn,
if the engine is hot enough. You
or others could be burned, and
the vehicle could be damaged.
Add brake fluid only when work is
done on the brake hydraulic
system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light 0139.
Brake fluid absorbs water over time
which degrades the effectiveness of
the brake fluid. Replace brake fluid
at the specified intervals to prevent
increased stopping distance. See
Maintenance Schedule 0441.
What to Add
Use only GM approved DOT 3 or
DOT 4 brake fluid, as indicated on
the reservoir cap, from a clean, sealed container. See
Recommended Fluids and
Lubricants
0452.
{Warning
The wrong or contaminated brake
fluid could result in damage to the
brake system. This could result in
the loss of braking leading to a
possible injury. Always use the
proper GM approved brake fluid.
Caution
If brake fluid is spilled on the
vehicle's painted surfaces, the
paint finish can be damaged.
Immediately wash off any painted
surface.
Battery - North America
The original equipment battery is
maintenance free. Do not remove
the cap and do not add fluid. Refer to the replacement number
shown on the original battery label
when a new battery is needed. See
Engine Compartment Overview
0
332 for battery location.
Stop/Start System
Vehicles equipped with a 2.7L L3B,
3.0L LM2, 5.3L L84 or 6.2L L87 are
equipped with a Stop/Start system
to shut off the engine to help
conserve fuel. See Stop/Start
System 0213.
Vehicles with the Stop/Start system
have an Absorbed Glass Mat (AGM)
12-volt battery. Installation of a
standard 12-volt battery will result in
reduced 12-volt battery life. When
using a 12-volt battery charger on
the 12-volt AGM battery, some
chargers have an AGM battery
setting on the charger. If available,
use the AGM setting on the charger
to limit charge voltage to 14.8 volts.
Follow the charger manufacturer ’s
instructions.