clock GMC SIERRA DENALI 2020 User Guide

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
368 Vehicle Care
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps
Base Level Taillamp Assembly
1. Stoplamp/Turn Signal Lamp
2. Back-Up Lamp
Uplevel Taillamp Assembly
See your dealer for taillamp
replacement.
It is recommended to replace the
grommets when replacing a bulb.
See your dealer.To replace one of these bulbs:
1. Open the tailgate.
2. Remove the two rear lamp assembly screws.
4. Pull the rear lamp assembly
outward and rearward away
from the box side to remove it
from the vehicle.
5. Turn the bulb socket counterclockwise.
6. Pull the bulb straight out from the socket.
7. Replace the bulb and reverse Steps 1–5 to reinstall.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 369
Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp
This procedure is for the regular cab
only. For crew cab and double cab
see your dealer.
1. Cargo Lamp Bulbs
2. Center High-MountedStoplamp (CHMSL) Bulb
To replace one of these bulbs:
1. Remove the two screws and lift off the lamp assembly.
2. Turn the bulb socket counterclockwise and pull it
straight out.
3. Pull the bulb straight out from the socket.
License Plate Lamp
To replace the bulb:
1. Reach behind the rear bumper and locate the bulb.
2. Turn the bulb socket counterclockwise and pull the
bulb straight out of the socket.
3. Replace the bulb and reverseStep 2 to reinstall.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 407
1. Wheel Block (If Equipped)
2. Flat Tire
The following information explains
how to use the jack and change
a tire.
Tire Changing
Removing the Spare Tire and
Tools
1. Jack
2. Jack Knob
3. Tool Kit
4. Wing Nut Retaining Tool Kit
5. Wheel Blocks6. Wing Nut Retaining Wheel
Blocks
The equipment is under the second
row seats, if equipped, or behind the
front row seats on regular cab
models.
1. Turn the knob on the jack counterclockwise to lower the
jack head to release the jack
from its holder.
2. Turn the wing nut counterclockwise to remove the
wheel blocks and the wheel
block retainer.
3. Turn the wing nut used to retain the storage bag and
tools counterclockwise to
remove it.
Use the jack handle extensions and
the wheel wrench to remove the
underbody-mounted spare tire.
1. Spare Tire (Valve Stem Pointed Down)
2. Tire/Wheel Retainer
3. Hoist Cable
4. Hoist Assembly
5. Hoist Shaft
6. Jack Handle Extensions
7. Wheel Wrench
8. Spare Tire Lock (If Equipped)
9. Hoist Shaft Access Hole
10. Hoist End of Extension Tool
1. Open the spare tire lock cover on the bumper and use the
ignition key to remove the
spare tire lock (8). To remove

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
408 Vehicle Care
the spare tire lock, insert the
ignition key, turn, and pull
straight out.
2. Assemble the wheel wrench (7)and the two jack handle
extensions (6), as shown.Spare Tire Cable (If Equipped)
3. If the vehicle is equipped with a spare tire cable disconnect the
cable from the attachment on
the frame by unclipping it from
the frame attachment bracket.
4. Insert the hoist end (openend) (10) of the extension
through the hole (9) in the rear
bumper.
Do not use the chiseled end of
the wheel wrench.
Be sure the hoist end of the
extension (10) connects to the
hoist shaft. The ribbed square
end of the extension is used to
lower the spare tire.
5. Turn the wheel wrench counterclockwise to lower the
spare tire to the ground.
Continue to turn the wheel
wrench until the spare tire can
be pulled out from under the
vehicle.
6. Pull the spare tire out from under the vehicle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
410 Vehicle Care
The tools you will be using include
the jack (1), the wheel blocks (2),
the jack handle (3), the jack handle
extensions (4), and the wheel
wrench (5).1. Do a safety check before proceeding. See If a Tire Goes
Flat 0405.
2. If the vehicle has wheel nut
caps, loosen them by turning
the wheel wrench
counterclockwise.
If the vehicle has a center cap
with wheel nut caps, the wheel
nut caps are designed to stay with the center cap after they
are loosened. Remove the
entire center cap.
If the wheel has a smooth
center cap, concealing access
to the wheel nuts, place the
chisel end of the wheel wrench
in the slot on the wheel, and
gently pry it out.
If the wheel’
s center cap does
not conceal the wheel nuts, the
center cap may remain during
wheel removal. If the removed
wheel is to be stowed in the
hoist, the cap needs to be
detached from the wheel.
Access the wheel from the back side, and use a jack
handle extension to push out
the center cap.
3. Use the wheel wrench and turn
it counterclockwise to loosen
the wheel nuts. Do not remove
the wheel nuts yet.
{Warning
To avoid personal injury and
vehicle damage, disable the
power assist steps before using a
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
412 Vehicle Care
Rear Position All Other ModelsFor all other models, position
the jack under the rear axle
between the spring anchor and
the shock absorber bracket.
If a snow plow has been added
to the front of the vehicle, lower
the snow plow fully before
raising the vehicle.
Make sure that the jack head is
positioned so that the rear axle
is resting securely between the
grooves that are on the
jack head.
{Warning
Getting under a vehicle when it is
lifted on a jack is dangerous.
If the vehicle slips off the jack,
you could be badly injured or
killed. Never get under a vehicle
when it is supported only by
a jack.
{Warning
Raising the vehicle with the jack
improperly positioned can
damage the vehicle and even
make the vehicle fall. To help
avoid personal injury and vehicle
damage, be sure to fit the jack lift
head into the proper location
before raising the vehicle.
6. Turn the wheel wrench clockwise to raise the vehicle.
Raise the vehicle far enough
off the ground so there is
enough room for the spare tire
to fit under the wheel well.
7. Remove all the wheel nuts andtake off the flat tire.
{Warning
Rust or dirt on a wheel, or on
the parts to which it is
fastened, can make wheel
nuts become loose after time.
The wheel could come off and
cause a crash. When
changing a wheel, remove any
rust or dirt from places where
the wheel attaches to the
vehicle. In an emergency, a
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 413
Warning (Continued)
cloth or a paper towel can be
used; however, use a scraper
or wire brush later to remove
all rust or dirt.
8. Remove any rust or dirt from the wheel bolts, mounting
surfaces, and spare wheel.
9. Install the spare tire.
{Warning
Never use oil or grease on bolts
or nuts because the nuts might
come loose. The vehicle's wheel
could fall off, causing a crash.
10. Put the wheel nuts back on with the rounded end of the
nuts toward the wheel.
11. Tighten each wheel nut by hand. Then use the wheel
wrench to tighten the nuts until
the wheel is held against
the hub.
12. Turn the wheel wrench counterclockwise to lower the
vehicle. Lower the jack
completely.
{Warning
If wheel studs are damaged, they
can break. If all the studs on a
wheel broke, the wheel could
come off and cause a crash.
(Continued)
Warning (Continued)
If any stud is damaged because
of a loose-running wheel, it could
be that all of the studs are
damaged. To be sure, replace all
studs on the wheel. If the stud
holes in a wheel have become
larger, the wheel could collapse in
operation. Replace any wheel if
its stud holes have become larger
or distorted in any way. Inspect
hubs and hub‐piloted wheels for
damage. Because of loose
running wheels, piloting pad
damage may occur and require
replacement of the entire hub, for
proper centering of the wheels.
When replacing studs, hubs,
wheel nuts or wheels, be sure to
use GM original equipment parts.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
414 Vehicle Care
{Warning
Wheel nuts that are improperly or
incorrectly tightened can cause
the wheels to become loose or
come off. The wheel nuts should
be tightened with a torque wrench
to the proper torque specification
after replacing. Follow the torque
specification supplied by the
aftermarket manufacturer when
using accessory locking wheel
nuts. SeeCapacities and
Specifications 0458 for original
equipment wheel nut torque
specifications.
Caution
Improperly tightened wheel nuts
can lead to brake pulsation and
rotor damage. To avoid expensive
brake repairs, evenly tighten the
wheel nuts in the proper
sequence and to the proper
(Continued)
Caution (Continued)
torque specification. See
Capacities and Specifications
0458 for the wheel nut torque
specification.
13. Tighten the nuts firmly in a crisscross sequence, as
shown, by turning the wheel
wrench clockwise.
For vehicles with dual wheels, have
a technician check the wheel nut
tightness of all wheels with a torque
wrench after the first 160, 1 600 and
10 000 km (100, 1,000 and 6,000 mi).
Repeat this service whenever you have a tire removed or serviced.
See
Capacities and Specifications
0 458.
When reinstalling the regular wheel
and tire, also reinstall either the
center cap, or bolt-on hub cap,
depending on what the vehicle is
equipped with. For center caps,
place the cap on the wheel and tap
it into place until it seats flush with
the wheel. The cap only goes on
one way. Be sure to line up the tab
on the center cap with the
indentation on the wheel. For
bolt-on hub caps, align the plastic
nut caps with the wheel nuts and
then tighten by hand. Then use the
wheel wrench to tighten.
Storing a Flat or Spare Tire
and Tools
{Warning
Storing a jack, a tire, or other
equipment in the passenger
compartment of the vehicle could
cause injury. In a sudden stop or (Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 417
5. Insert the hoist end (10)through the hole (9) in the rear
bumper and onto the hoist
shaft.
Do not use the chiseled end of
the wheel wrench.
6. Raise the tire part way upward. Make sure the retainer is
seated in the wheel opening.
7. If equipped with a spare tirecable, orient the cable by
rotating the spare tire so that
the cable is by the frame
attachment location.
8. Raise the tire fully against the underside of the vehicle by
turning the wheel wrench
clockwise until you hear two
clicks or feel it skip twice. You
cannot overtighten the cable.9. Make sure the tire is storedsecurely. Push, pull, and then
try to turn the tire. If the tire
moves, use the wheel wrench
to tighten the cable.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-13337776) - 2020 - CRC - 8/27/19
Index 489
Caution, Danger, and Warning . . . . 3
Center Console Storage . . . . . . . . 113
Center High-MountedStoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . . . 369
Center Seat . . . . . . . . . . . . . . . . . . . . . 55
Chains, Tire . . . . . . . . . . . . . . . . . . . . 404
Charging Wireless . . . . . . . . . . . . . . . . . . . . . . 122
Charging System Light . . . . . . . . . 137
Check Engine Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . 137
Ignition Transmission Lock . . . 363
Child Restraints Infants and Young Children . . . . . 86
Lower Anchors and Tethers
for Children . . . . . . . . . . . . . . . . . . . 91
Older Children . . . . . . . . . . . . . . . . . . 84
Securing . . . . . . . . . . . . 104, 107, 108
Systems . . . . . . . . . . . . . . . . . . . . . . . . 88
Circuit Breakers . . . . . . . . . . . . . . . . 370
Cleaning Exterior Care . . . . . . . . . . . . . . . . . 429
Interior Care . . . . . . . . . . . . . . . . . . 435
Climate Control Systems . . . . . . . 177 Air Conditioning . . . . . . . . . . . . . . 177
Dual Automatic . . . . . . . . . . . . . . . 179 Climate Control Systems (cont'd)
Heating . . . . . . . . . . . . . . . . . . . . . . . 177
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . 120
Cluster, Instrument . . . . . . . . . . . . . 126
Collision Damage Repair . . . . . . . 469
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . .112
Compass . . . . . . . . . . . . . . . . . . . . . . . 120
Connected Services Connections . . . . . . . . . . . . . . . . . . 485
Diagnostics . . . . . . . . . . . . . . . . . . . 486
Navigation . . . . . . . . . . . . . . . . . . . . 484
Connections Connected Services . . . . . . . . . . 485
Control Hill Descent . . . . . . . . . . . . . . . . . . 237
Traction and ElectronicStability . . . . . . . . . . . . . . . . . . . . . 235
Control Light Hill Descent . . . . . . . . . . . . . . . . . . 141
Control of a Vehicle . . . . . . . . . . . . . 188
Convex Mirrors . . . . . . . . . . . . . . . . . . 39
Coolant Engine Temperature Gauge . . 133
Engine TemperatureWarning Light . . . . . . . . . . . . . . . 144
Cooling . . . . . . . . . . . . . . . . . . . . 177, 179
Cooling System . . . . . . . . . . . . . . . . . 346 Courtesy Transportation
Program . . . . . . . . . . . . . . . . . . . . . . . 468
Cruise Control . . . . . . . . . . . . . . . . . . 243 Light . . . . . . . . . . . . . . . . . . . . . . . . . . 146
Cruise Control, Adaptive . . . . . . . . 245
Cupholders . . . . . . . . . . . . . . . . . . . . . 112
Customer Assistance . . . . . . . . . . . 465 Offices . . . . . . . . . . . . . . . . . . . . . . . . 464
Text Telephone (TTY)Users . . . . . . . . . . . . . . . . . . . . . . . 465
Customer Information
Publications OrderingInformation . . . . . . . . . . . . . . . . . . 471
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . . . 462
Cybersecurity . . . . . . . . . . . . . . . . . . . 474
D
Damage Repair, Collision . . . . . . . 469
Danger, Warning, and Caution . . . . 3
Data Collection
Infotainment System . . . . . . . . . . 475
OnStar . . . . . . . . . . . . . . . . . . . . . . . 475
Data Recorders, Event . . . . . . . . . 474
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . 168
Defensive Driving . . . . . . . . . . . . . . . 187
Delayed Locking . . . . . . . . . . . . . . . . . 27