
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 243
*:Press to disengage ACC without erasing
the selected set speed.
[: Press to select a following gap setting
for ACC of Far, Medium, or Near.
The speedometer reading can be displayed
in either English or metric units. See
Instrument Cluster (Base Level) 0112 or
Instrument Cluster (Uplevel) 0113. The
increment value used depends on the units
displayed.
Switching Between ACC and Regular Cruise
Control
To switch between ACC and regular cruise
control, press and hold
*. A Driver
Information Display (DIC) message displays.
See Vehicle Messages 0139.
ACC Indicator (Base
Level)ACC Indicator (Uplevel)
Regular Cruise Control Indicator
When ACC is engaged, a green
oor\
indicator will be lit on the instrument cluster
and the following gap will be displayed.
When the regular cruise control is engaged,
a green
Jindicator will be lit on the
instrument cluster; the following gap will
not display.
When the vehicle is turned on, the cruise
control mode will be set to the last mode
used before the vehicle was turned off.
{Warning
Always check the cruise control indicator
on the instrument cluster to determine
which mode cruise control is in before
using the feature. If ACC is not active, the
vehicle will not automatically brake for
other vehicles, which could cause a crash
(Continued)
Warning (Continued)
if the brakes are not applied manually.
You and others could be seriously injured
or killed.
Setting Adaptive Cruise Control
If
Jis on when not in use, SET–/RES+
could be pressed by mistake and engage
ACC when not desired. Keep
Joff when
cruise is not being used.
Select the set speed desired for ACC. This is
the vehicle speed when no vehicle is
detected in your path.
While the vehicle is moving, ACC will not set
at a speed lower than 5 km/h (3 mph),
although it can be resumed. The minimum
allowable set speed is 25 km/h (15 mph).
To set ACC while moving:
1. Press
J.
2. Get up to the desired speed.
3. Press and release SET–.
4. Remove foot from the accelerator.
After ACC is set, it may immediately apply
the brakes if a vehicle ahead is detected
closer than the selected following gap.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
248 Driving and Operating
Irregular Objects Affecting ACC
ACC may have difficulty detecting the
following objects:
.Vehicles in front of your vehicle that have
a rear aspect that is low, small,
or irregular
.An empty truck or trailer that has no
cargo in the cargo bed
.Vehicles with cargo extending from the
back end
.Non-standard shaped vehicles, such as
vehicle transport, vehicles with a side car
fitted, or horse carriages
.Vehicles that are low to the road surface
.Objects that are close to the front of your
vehicle
.Vehicles on which extremely heavy cargo
is loaded in the cargo area or rear seat
ACC Automatically Disengages
ACC may automatically disengage and the
driver will need to manually apply the
brakes to slow the vehicle if:
.The front camera is blocked or visibility is
reduced.
.The Traction Control System (TCS) or
StabiliTrak/ESC system has activated or
been disabled.
.There is a fault in the system.
.A DIC message displays to indicate that
ACC is temporarily unavailable.
The ACC indicator will turn white when ACC
is no longer active.
In some cases, when ACC is temporarily
unavailable, regular cruise control may be
used. See “Switching Between ACC and
Regular Cruise Control” previously in this
section. Always consider driving conditions
before using either cruise control system.
Notification to Resume ACC
ACC will maintain a follow gap behind a
detected vehicle and slow your vehicle to a
stop behind that vehicle. If the stopped vehicle ahead has driven
away and ACC has not resumed, the vehicle
ahead indicator will flash as a reminder to
check traffic ahead before proceeding. In
addition, the left and right sides of the
Safety Alert Seat (if equipped) will pulse
three times, or three beeps will sound. To
view available settings from the
infotainment screen, touch Settings >
Vehicle > Collision/Detection Systems > Alert
Type > Adaptive Cruise Go Notifier.
When the vehicle ahead drives away, ACC
resumes automatically if the stop was brief.
If necessary, press RES+ or the accelerator
pedal to resume ACC. If stopped for more
than two minutes or if the driver door is
opened and the driver seat belt is
unbuckled, the ACC automatically applies the
Electric Parking Brake (EPB) to hold the
vehicle. The EPB status light will turn on.
See
Electric Parking Brake 0234. To release
the EPB, press the accelerator pedal.
A DIC warning message may display
indicating to shift to P (Park) before exiting
the vehicle. See Vehicle Messages 0139.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 265
shows the current setting on the DIC.
Additional button presses will change this
setting. The chosen setting will remain until
it is changed and will affect the timing of
both the Collision Alert and the Tailgating
Alert features. The timing of both alerts will
vary based on vehicle speed. The faster the
vehicle speed, the farther away the alert will
occur. Consider traffic and weather
conditions when selecting the alert timing.
The range of selectable alert timings may
not be appropriate for all drivers and driving
conditions.
If your vehicle is equipped with Adaptive
Cruise Control (ACC), changing the FCA
timing setting automatically changes the
following gap setting (Far, Medium,
or Near).
Following Distance Indicator
If equipped, the following distance to a
moving vehicle ahead in your path is
indicated in following time in seconds on
the Driver Information Center (DIC). See
Driver Information Center (DIC) (Base Level)
0131 or
Driver Information Center (DIC) (Uplevel)
0 133. The minimum following time is
0.5 seconds away. If there is no vehicle detected ahead, or the
vehicle ahead is out of sensor range, dashes
will be displayed.
Unnecessary Alerts
FCA may provide unnecessary alerts for
turning vehicles, vehicles in other lanes,
objects that are not vehicles, or shadows.
These alerts are normal operation and the
vehicle does not need service.
Cleaning the System
If the FCA system does not seem to operate
properly, this may correct the issue:
.Clean the outside of the windshield in
front of the rearview mirror.
.Clean the entire front of the vehicle.
.Clean the headlamps.
Automatic Emergency
Braking (AEB)
If equipped, AEB may help avoid or reduce
the harm caused by front-end crashes. AEB
also includes Intelligent Brake Assist (IBA).
When the system detects a vehicle ahead in
your path that is traveling in the same
direction that you may be about to crash
into, it can provide a boost to braking or
automatically brake the vehicle. This canhelp avoid or lessen the severity of crashes
when driving in a forward gear. Depending
on the situation, the vehicle may
automatically brake moderately or hard. This
automatic emergency braking can only occur
if a vehicle is detected. This is shown by the
FCA vehicle ahead indicator being lit. See
Forward Collision Alert (FCA) System
0263.
The system works when driving in a forward
gear between 8 km/h (5 mph) and 80 km/h
(50 mph). It can detect vehicles up to
approximately 60 m (197 ft).
{Warning
AEB is an emergency crash preparation
feature and is not designed to avoid
crashes. Do not rely on AEB to brake the
vehicle. AEB will not brake outside of its
operating speed range and only responds
to detected vehicles.
AEB may not:
.Detect a vehicle ahead on winding or
hilly roads.
.Detect all vehicles, especially vehicles
with a trailer, tractors, muddy
vehicles, etc. (Continued)

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Driving and Operating 277
The following information has many
time-tested, important trailering tips and
safety rules. Many of these are important
for your safety and that of your passengers.
Read this section carefully before towing a
trailer.
When towing a trailer:
.Become familiar with, and follow all state
and local laws that apply to trailer
towing. These requirements vary from
state to state.
.State laws may require the use of
extended side view mirrors. If your
visibility is limited or restricted while
towing, install extended side view mirrors
on your vehicle, even if not required.
.Do not tow a trailer during the first
800 km (500 mi) of vehicle use to prevent
damage to the engine, axle, or other
parts.
.Perform the first oil change before heavy
towing.
.Do not drive over 80 km/h (50 mph) and
do not make starts at full throttle during
the first 800 km (500 mi) of trailer
towing.
.Tow in D (Drive). Tow/Haul Mode is
recommended for heavier trailers. See
Tow/Haul Mode0227. If the transmission
downshifts too often, a lower gear may
be selected using Manual Mode. See
Manual Mode 0226.
The following advanced driver assistance
features should be turned off when towing
a trailer, and may turn off automatically
when a trailer is detected:
.Park Assist
.Reverse Automatic Braking (RAB)
.Rear Cross Traffic Alert (RCTA)
.Rear Cross Traffic Braking (RCTB)
.Lane Change Alert (LCA)
.Super Cruise and Adaptive Cruise Control
(ACC), unless equipped with trailering
functionality, see Adaptive Cruise Control
(Camera) 0241.
Automatic Emergency Braking (AEB) and
Front Pedestrian Braking (FPB) should be set
to Alert unless equipped with Super Cruise.
Do not use Automatic Parking Assist (APA)
while towing a trailer.
{Warning
To prevent serious injury or death from
carbon monoxide (CO), when towing a
trailer:
.Do not drive with the liftgate, trunk/
hatch, or rear-most window open.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to a
setting that brings in only outside air.
See “Climate Control Systems” in the
Index.
For more information about carbon
monoxide, see Engine Exhaust 0222.
Towing a trailer requires experience. The
combination of the vehicle and trailer is
longer and not as responsive as the vehicle
itself. Get used to the handling and braking
of the combination by driving on a level
road surface before driving on public roads.
The trailer structure, the tires, and the
brakes must all be rated to carry the
intended cargo. Inadequate trailer
equipment can cause the combination to
operate in an unexpected or unsafe manner.
Before driving, inspect all trailer hitch parts

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Index 425
IndexA
Accessories and Modifications . . . . . . . . . . . 310
Accessory Power . . . . . . . . . . . . . . . . . . . . . . . . . 220
AdaptiveCruise Control . . . . . . . . . . . . . . . . . . . . . . . . . 241
Add-On Electrical Equipment . . . . . . . . . . . . . 306
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Additional OnStar Information . . . . . . . . . . . . . . . . . . . . 419
Adjustments Lumbar, Front Seats . . . . . . . . . . . . . . . . . . . . 50
Advanced Driver Assistance Systems . . . . . . . . . . . . . 252
Agreements Trademarks and License . . . . . . . . . . . . . . . 188
Air Cleaner/Filter, Engine . . . . . . . . . . . . . . . . . . 318
Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . . . 193
Filter Life System . . . . . . . . . . . . . . . . . . . . . . . 317
Filter, Passenger Compartment . . . . . . . . 196
Vents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 196
Air Conditioning . . . . . . . . . . . . . . . . . . . . . . . . . . 191
Airbag System . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64 Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
How Does an Airbag Restrain? . . . . . . . . . . 68
Passenger Sensing System . . . . . . . . . . . . . . 69
What Makes an Airbag Inflate? . . . . . . . . . 68 Airbag System (cont'd)
What Will You See after an Airbag
Inflates? . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
When Should an Airbag Inflate? . . . . . . . . 67
Where Are the Airbags? . . . . . . . . . . . . . . . . 66
Airbags Adding Equipment to the Vehicle . . . . . . . 73
Passenger Status Indicator . . . . . . . . . . . . . . 121
Readiness Light . . . . . . . . . . . . . . . . . . . . . . . . . 121
Replacing System Parts after a
Crash . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Servicing Airbag-Equipped Vehicles . . . . . . 73
Alarm Vehicle Security . . . . . . . . . . . . . . . . . . . . . . . . 32
Alert Lane Change (LCA) . . . . . . . . . . . . . . . . . . . . . 268
Rear Cross Traffic . . . . . . . . . . . . . . . . . . . . . . 263
All-Season Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 345
All-Terrain Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 346
AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . . . 159, 161
Antenna Multi-band . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Antilock Brake System (ABS) . . . . . . . . . . . . . 233 Warning Light . . . . . . . . . . . . . . . . . . . . . . . . . 125
Appearance Care Exterior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Interior . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 388
Apple CarPlay and Android Auto . . . . . 177, 179

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
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Index 427
Canadian Vehicle Owners . . . . . . . . . . . . . . . . . . .2
Capacities and Specifications . . . . . . . . . . . . . 402
Carbon MonoxideEngine Exhaust . . . . . . . . . . . . . . . . . . . . . . . . 222
Tailgate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 24
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . 207
Cargo
Tie-Downs . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Caution, Danger, and Warning . . . . . . . . . . . . . .2
Center High-Mounted Stoplamp (CHMSL)
and Cargo Lamp . . . . . . . . . . . . . . . . . . . . . 335
Seat . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 48
Center Console Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 101
Chains, Tire . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 363
Charging
System Light . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Wireless . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 109
Check Engine Light (Malfunction Indicator) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 122
Child Restraints Infants and Young Children . . . . . . . . . . . . . 76
Lower Anchors and Tethers forChildren . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 81
Older Children . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Securing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 92, 95
Systems . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 78 Child Safety Locks . . . . . . . . . . . . . . . . . . . . . . . . 24
Circuit Breakers . . . . . . . . . . . . . . . . . . . . . . . . . . 337
Cleaning
Exterior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 383
Interior Care . . . . . . . . . . . . . . . . . . . . . . . . . . . 388
Climate Control Systems . . . . . . . . . . . . . . . . . . 191 Air Conditioning . . . . . . . . . . . . . . . . . . . . . . . . 191
Dual Automatic . . . . . . . . . . . . . . . . . . . . . . . . 193
Heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Cluster, Instrument . . . . . . . . . . . . . . . . . . . 112, 113
Collision Alert Forward (FCA) System . . . . . . . . . . . . . . . . . 263
Collision Damage Repair . . . . . . . . . . . . . . . . . . 411
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 99
Compass . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107
Connected Services Connections . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Diagnostics . . . . . . . . . . . . . . . . . . . . . . . . . . . . 424
Navigation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 422
Connections Connected Services . . . . . . . . . . . . . . . . . . . . 422
Control Hill Descent . . . . . . . . . . . . . . . . . . . . . . . . . . . . 237
Traction and Electronic Stability . . . . . . . 236
Control Light Hill Descent . . . . . . . . . . . . . . . . . . . . . . . . . . . . 126 Control of a Vehicle . . . . . . . . . . . . . . . . . . . . . 200
Controls
Steering Wheel . . . . . . . . . . . . . . . . . . . . . . . . 156
Convex Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . 34
Coolant Engine Temperature Gauge . . . . . . . . . . . . . 118
Engine Temperature Warning Light . . . . 128
Cooling . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 191, 193
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . . . 319
Courtesy Transportation Program . . . . . . . . 410
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . . . 239 Adaptive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Cupholders . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Customer Assistance Offices . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 407
Text Telephone (TTY) Users . . . . . . . . . . . . 407
Customer Information Publications Ordering Information . . . . . 413
Customer Satisfaction Procedure . . . . . . . . . 405
Cybersecurity . . . . . . . . . . . . . . . . . . . . . . . . . . . . .415
D
Damage Repair, Collision . . . . . . . . . . . . . . . . . . 411
Danger, Warning, and Caution . . . . . . . . . . . . . .2
Dashboard . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
Data Collection Infotainment System . . . . . . . . . . . . . . . . . . 416