lane assist GMC SIERRA 2023 Owners Manual

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Introduction 3
A circle with a slash through it is a safety
symbol which means“Do not,” “Do not do
this,” or“Do not let this happen.”
Symbols
The vehicle has components and labels that
use symbols instead of text. Symbols are
shown along with the text describing the
operation or information relating to a
specific component, control, message, gauge,
or indicator.
M:Shown when the owner’s manual has
additional instructions or information.
*: Shown when the service manual has
additional instructions or information.
0: Shown when there is more information
on another page — “see page.” Vehicle Symbol Chart
Here are some additional symbols that may
be found on the vehicle and what they
mean. See the features in this manual for
information.
u:
Air Conditioning System
G:Air Conditioning Refrigerant Oil
9:Airbag Readiness Light
!:Antilock Brake System (ABS)
$:Brake System Warning Light
9:Dispose of Used Components Properly
P:Do Not Apply High Pressure Water
B:Engine Coolant Temperature
_:Flame/Fire Prohibited
H: Flammable
[:Forward Collision Alert
R:Fuse Block Cover Lock Location
+:Fuses
j:ISOFIX/LATCH System Child Restraints
Q:Keep Fuse Block Covers Properly
Installed
|: Lane Change Alert
@:Lane Departure Warning
A:Lane Keep Assist
*: Malfunction Indicator Lamp
::Oil Pressure
X:Park Assist
~:Pedestrian Ahead Indicator
O:Power
7:Rear Cross Traffic Alert
I:Registered Technician
/:Remote Vehicle Start
h:Risk of Electrical Fire

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
6 Introduction
1. Tow/Haul Mode (On Some Models). SeeDriver Mode Control 0243.
Automatic Transfer Case Control (If
Equipped). See Four-Wheel Drive 0234.
Driver Mode Control 0243 (If Equipped).
2. Air Vents 0201.
3. Head-Up Display (HUD) 0132 (If
Equipped).
4. Turn Signal Lever. See Turn and
Lane-Change Signals 0143.
Windshield Wiper/Washer 0106.
5. Instrument Cluster 0111.
6. Shift Lever. See Automatic Transmission
0 230.
Range Selection Mode. See Manual Mode
0 232.
7. Light Sensor. See Automatic Headlamp
System 0141.
8. Infotainment Controls. See Overview
0 149.
9. Climate Control Systems 0196 (If
Equipped).
Dual Automatic Climate Control System
0 197 (If Equipped).
10. Heated and Ventilated Front Seats 056
(If Equipped). 11.XPark Assist Switch (If Equipped). See
Assistance Systems for Parking or Backing
0 248.
5Power Release Tailgate (If
Equipped). See Tailgate026.
|Hazard Warning Flashers 0142.
gTraction Control/Electronic Stability
Control 0241.
-DC/AC Switch. See Power Outlets
0 107.
@Lane Departure Warning (LDW) 0262
(If Equipped).
5Hill Descent Control Switch (If
Equipped). See Hill Descent Control (HDC)
0 242.
jPower Assist Steps 033 (If
Equipped).
LExpress Window Down Button (If
Equipped). See Power Windows 044.
Tow/Haul Mode 0234 (On Some
Models).
Exhaust Brake (If Equipped). See Duramax
Diesel Supplement.
Power Take-Off (PTO) (If Equipped). See
Duramax Diesel Supplement. 12. Power Outlet (Alternating Current) (If
Equipped). See Power Outlets0107.
13. Power Outlets 0107.
14. USB Port 0158.
15. Wireless Charging 0109 (If Equipped).
16. Trailer Brake Control Panel (If Equipped). See“Integrated Trailer Brake Control
System” underTowing Equipment 0276.
17. ENGINE START/STOP. See Ignition
Positions (Key Access) 0221 or
Ignition Positions (Keyless Access) 0223.
18. Steering Wheel Controls 0151 (If
Equipped).
Driver Information Center (DIC) Controls.
See Driver Information Center (DIC) (Base
Level) 0128 or
Driver Information Center (DIC) (Midlevel
and Uplevel) 0130.
19. Horn 0106.
20. Hood Release. See Hood0303.
21. Steering Wheel Adjustment 0105 (Out
of View).
22. Cruise Control 0244.
Forward Collision Alert (FCA) System
0 257 (If Equipped).
Heated Steering Wheel 0105 (If
Equipped).

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
38 Keys, Doors, and Windows
If a popping noise from the mirror is heard,
this sound is normal as the manual detents
are aligning after a manual extend/retract
operation has occurred.
Auxiliary Cargo Mirror Lamps
If equipped, cargo mirror lamps face
rearward to provide more light on the sides
of the vehicle, if needed. SeeExterior Cargo
Lamps 0144.
Advanced Trailering Vision System Side
Cameras
If equipped, the Advanced Trailering Vision
System side cameras are on the bottom of
the outside mirrors. See “Surround Vision
(360 Degrees)” underAssistance Systems for
Parking or Backing 0248.Power Mirrors
To adjust each mirror:
1. Press
jor|to select the driver or
passenger side mirror. The indicator light
will illuminate.
2. Press the arrows on the control pad to move the mirror in the desired direction.
3. Adjust each outside mirror so that a little of the vehicle and the area behind it can
be seen.
4. Press
jor|again to deselect the
mirror. Turn Signal Indicator
If equipped, the mirror has turn signal
indicator lights, which flash in the direction
of the turn or lane change.
Task Lighting
If equipped, task lighting projects light from
the outside mirrors to the sides of the
vehicle. See
Task Lighting 0144.
Puddle Lamps
If equipped, puddle lamps project light from
the bottom of the mirror to the area of
ground below the driver and passenger
doors. See Entry Lighting 0146 and
Exit Lighting 0146.
Memory Mirrors
The vehicle may have memory mirrors. See
Memory Seats 053.
Lane Change Alert (LCA)
The vehicle may have LCA. See Lane Change
Alert (LCA) 0261.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
124 Instruments and Controls
Lane Departure Warning (LDW)
Light
This light is green if LDW is on and ready to
operate.
This light changes to amber and flashes to
indicate that the lane marking has been
crossed without using a turn signal in that
direction.
SeeLane Departure Warning (LDW) 0262.
Vehicle Ahead Indicator
If equipped, this indicator will display green
when a vehicle is detected ahead and amber
when you are following a vehicle ahead
much too closely. See
Forward Collision Alert (FCA) System
0 257.
Traction Off Light
This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem.
The traction off light comes on when the
Traction Control System (TCS) has been
turned off. If Electronic Stability Control
(ESC) is turned off, TCS is also turned off. To
turn TCS and ESC off and on, see Traction
Control/Electronic Stability Control 0241.
If TCS is off, wheel slip during acceleration is
not limited unless necessary to help protect
the driveline from damage. Adjust driving
accordingly.
Traction Control System (TCS)/
Electronic Stability Control Light
This light comes on briefly when the vehicle
is turned on to show that the light is
working. If it does not come on then, have
it fixed so it will be ready to warn you if
there is a problem.
If the light is on and not flashing, the TCS
and potentially the ESC system are not fully
operational and may not assist in
maintaining control. Adjust driving
accordingly. If the condition persists, see
your dealer as soon as possible. A Driver
Information Center (DIC) message may
display.
The light flashes when the TCS and/or the
ESC system is actively working.
See Traction Control/Electronic Stability
Control 0241.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
132 Instruments and Controls
Engine Hours (Hourmeter) :Shows the total
number of hours the engine has run. This
display also shows the engine idle hours.
Transmission Fluid Temperature : Shows the
temperature of the automatic transmission
fluid in either degrees Celsius (°C) or degrees
Fahrenheit (°F).
Trailer Brake : On vehicles with the
Integrated Trailer Brake Control (ITBC)
system, the trailer brake display appears in
the DIC.
TRAILER GAIN shows the trailer gain setting.
This setting can be adjusted from 0.0 to 10.0
with either a trailer connected or
disconnected.
TRAILER OUTPUT shows the power output to
the trailer any time a trailer with electric
brakes is connected. Output is displayed as a
bar graph. Dotted lines may appear in the
OUTPUT display if a trailer is not connected.
Off Road : Displays vehicle pitch and roll
information, road wheel angle, and
four-wheel drive (4WD) status.
Follow Distance : If equipped, the current
follow time to the vehicle ahead is displayed
as a time value on this page. Driver Assistance :
If equipped, shows
information for Lane Departure Warning
(LDW) and Forward Collision Alert (FCA).
Info Page Options : Scroll to choose which
info pages appear on the DIC. Press the
thumbwheel to select or deselect.
Blank Page : Shows no information.
Head-Up Display (HUD)
{Warning
If the HUD image is too bright or too
high in your field of view, it may take
you more time to see things you need to
see when it is dark outside. Be sure to
keep the HUD image dim and placed low
in your field of view.
If equipped with HUD, some information
about the operation of the vehicle is
projected onto the windshield. The image is
projected through the HUD lens on top of
the instrument panel. The information
appears as an image focused out toward the
front of the vehicle.
Caution
If you try to use the HUD image as a
parking aid, you may misjudge the
distance and damage your vehicle. Do not
use the HUD image as a parking aid.
The HUD information can be displayed in
various languages. The speedometer reading
and other numerical values can be displayed
in either English or metric units.
The language selection is changed through
the radio, and the units of measurement are
changed through the instrument cluster. See
Settings 0182 and “Options” under
Instrument Cluster 0111.
HUD Display on the Windshield

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
134 Instruments and Controls
Speed View :This displays the speedometer
reading in English or metric units, and speed
limit. Some information only appears on
vehicles that have these features, and when
they are active.
English Shown, Metric Similar
Active Safety View : This displays the speed
view along with a driver assistance graphic
on the left. Driver assistance graphics show
your vehicle, vehicle ahead, gap setting, and
lane status information. In addition to driver
assistance graphics, pedestrian advisory and
trailer sway indicators will be displayed.
English Shown, Metric Similar
Navigation/Active OnStar View : This
displays the speed view along with
indicators for vehicle ahead, Lane Departure
Warning, trailer sway, and pedestrian
advisory. Turn-by-Turn navigation
information is shown during active route.
The compass heading is displayed when
navigation routing is not active.
Navigation Turn-by-Turn Alerts shown in the
instrument cluster may also be displayed in
any HUD view.English Shown, Metric Similar
Off Road View : This displays the speed
view along with indicators for vehicle ahead,
Lane Departure Warning, trailer sway,
four-wheel drive status, and pedestrian
advisory. Off-road information such as pitch
angle, steering angle, and rolling angle is
also shown.
Care of the HUD
Clean the inside of the windshield to remove
any dirt or film that could reduce the
sharpness or clarity of the HUD image.
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.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Driving and Operating 203
Driving and Operating
Driving Information
Driving for Better Fuel Economy . . . . . . 204
Distracted Driving . . . . . . . . . . . . . . . . . . . . . 204
Defensive Driving . . . . . . . . . . . . . . . . . . . . . 205
Impaired Driving . . . . . . . . . . . . . . . . . . . . . . 205
Control of a Vehicle . . . . . . . . . . . . . . . . . . . 205
Braking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 205
Steering . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . 207
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . 207
Off-Road Driving . . . . . . . . . . . . . . . . . . . . . . 208
Driving on Wet Roads . . . . . . . . . . . . . . . . . . 211
Hill and Mountain Roads . . . . . . . . . . . . . . 212
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . 212
If the Vehicle Is Stuck . . . . . . . . . . . . . . . . . 214
Vehicle Load Limits . . . . . . . . . . . . . . . . . . . . 215
Truck-Camper Loading Information . . . . . 219
Starting and Operating
New Vehicle Break-In . . . . . . . . . . . . . . . . . . 221
Ignition Positions (Key Access) . . . . . . . . . 221
Ignition Positions (Keyless Access) . . . . . 223
Starting the Engine . . . . . . . . . . . . . . . . . . . . 225
Engine Heater . . . . . . . . . . . . . . . . . . . . . . . . . 226
Retained Accessory Power (RAP) . . . . . . . 227
Shifting Into Park . . . . . . . . . . . . . . . . . . . . . . 227
Shifting out of Park . . . . . . . . . . . . . . . . . . . 228Parking over Things That Burn . . . . . . . . 229
Extended Parking . . . . . . . . . . . . . . . . . . . . . . 229
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . . . . . . . . . . . 229
Running the Vehicle While Parked . . . . . 230
Automatic Transmission
Automatic Transmission . . . . . . . . . . . . . . . 230
Manual Mode . . . . . . . . . . . . . . . . . . . . . . . . . 232
Tow/Haul Mode . . . . . . . . . . . . . . . . . . . . . . . 234
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 234
Brakes
Antilock Brake System (ABS) . . . . . . . . . . 238
Electric Parking Brake . . . . . . . . . . . . . . . . . 239
Brake Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . 240
Hill Start Assist (HSA) . . . . . . . . . . . . . . . . . 240
Ride Control Systems
Traction Control/Electronic Stability
Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 241
Hill Descent Control (HDC) . . . . . . . . . . . . . 242
Driver Mode Control . . . . . . . . . . . . . . . . . . . 243
Locking Rear Axle . . . . . . . . . . . . . . . . . . . . . 244
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . . . . . . . . . . 244
Driver Assistance Systems
Driver Assistance Systems . . . . . . . . . . . . . 246
Assistance Systems for Parking or Backing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 248
Rear Vision Camera (RVC) . . . . . . . . . . . . . 248
Surround Vision System . . . . . . . . . . . . . . . 249
Park Assist . . . . . . . . . . . . . . . . . . . . . . . . . . . . 256
Rear Cross Traffic Alert (RCTA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
Assistance Systems for Driving . . . . . . . . 257
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 257
Automatic Emergency Braking (AEB) . . . . . . . . . . . . . . . . . . . . . . . . 259
Side Blind Zone Alert (SBZA) . . . . . . . . . . 260
Lane Change Alert (LCA) . . . . . . . . . . . . . . . 261
Lane Departure Warning (LDW) . . . . . . . 262
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 263
Recommended Fuel . . . . . . . . . . . . . . . . . . . . 263
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . 264
Fuels in Foreign Countries . . . . . . . . . . . . . 264
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . 264
E85 or FlexFuel . . . . . . . . . . . . . . . . . . . . . . . . 264
Filling the Tank (Pickup Models) . . . . . . . 265
Filling the Tank (Chassis Cab and Box Delete Models) . . . . . . . . . . . . . . . . . . . . . . 266
Filling a Portable Fuel Container . . . . . . 268

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
206 Driving and Operating
Steering
Caution
To avoid damage to the steering system,
do not drive over curbs, parking barriers,
or similar objects at speeds greater than
3 km/h (1 mph). Use care when driving
over other objects such as lane dividers
and speed bumps. Damage caused by
misuse of the vehicle is not covered by
the vehicle warranty.
Hydraulic Power Steering (2500/3500
Series)
(2500/3500 Series–All Regular Cab, Double
Cab/Crew Cab with Base Interior)
The power steering system may require
maintenance. See Power Steering Fluid 0315.
If power steering assist is lost because the
engine stops or the system malfunctions,
the vehicle can be steered but may require
increased effort. See your dealer.
(2500/3500 Series –Double Cab/Crew Cab
with Uplevel Interior)
The vehicle has a power steering system
that varies the amount of effort required to
steer the vehicle. Less steering effort is
required at slower speeds. At faster speeds,
the required steering effort increases. The
system helps the steering wheel return to
center at low speeds. Pressing the Tow/Haul
mode button adjusts steering effort for
driving conditions described in Tow/Haul
Mode 0234.
The power steering system may require
maintenance. See Power Steering Fluid 0315. If power steering assist is lost because the
engine stops or the system malfunctions,
the vehicle can be steered but may require
increased effort. See your dealer.
{Warning
Do not hold the brake pedal and press
the accelerator pedal at the same time.
Damage may occur to the power steering
and power brake systems which could
lead to reduced performance, up to and
including loss of steering and brake
assist.
Caution
Do not hold the steering wheel at full
rotation for more than 15 seconds and/or
at an elevated RPM. Damage may occur
to the power steering system and there
may be loss of power steering assist.
Curve Tips
.Take curves at a reasonable speed.
.Reduce speed before entering a curve.
.Maintain a reasonable steady speed
through the curve.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
212 Driving and Operating
Hydroplaning
Hydroplaning is dangerous. Water can build
up under the vehicle's tires so they actually
ride on the water. This can happen if the
road is wet enough and you are going fast
enough. When the vehicle is hydroplaning, it
has little or no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to slow
down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather
driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping equipment in
good shape.
.Keep the windshield washer fluid reservoir
filled.
.Have good tires with proper tread depth.
SeeTires 0337.
.Turn off cruise control.
Hill and Mountain Roads
Driving on steep hills or through mountains
is different than driving on flat or rolling
terrain. Tips include:
.Keep the vehicle serviced and in good
shape.
.Check all fluid levels and brakes, tires, and
cooling system.
.Shift to a lower gear when going down
steep or long hills.
{Warning
Using the brakes to slow the vehicle on a
long downhill slope can cause brake
overheating, can reduce brake
performance, and could result in a loss of
braking. Shift the transmission to a lower
gear to let the engine assist the brakes
on a steep downhill slope.
{Warning
Coasting downhill in N (Neutral) or with
the ignition off is dangerous. This can
cause overheating of the brakes and loss
of steering assist. Always have the engine
running and the vehicle in gear.
.Drive at speeds that keep the vehicle in
its own lane. Do not swing wide or cross
the center line.
.Be alert on top of hills; something could
be in your lane (e.g., stalled car, crash).
.Pay attention to special road signs (e.g.,
falling rocks area, winding roads, long
grades, passing or no-passing zones) and
take appropriate action.
Winter Driving
Driving on Snow or Ice
Caution
To avoid damage to the wheels and
brake components, always clear snow and
ice from inside the wheels and
underneath the vehicle before driving.
Snow or ice between the tires and the road
creates less traction or grip, so drive
carefully. Wet ice can occur at about 0 °C
(32 °F) when freezing rain begins to fall.
Avoid driving on wet ice or in freezing rain
until roads can be treated.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16504257) - 2023 - CRC - 5/9/22
Driving and Operating 257
vehicle personalization. The On with Towbar
setting allows Park Assist to work properly
with a trailer hitch. Some larger trailer
hitches may not be compatible.
To view available settings for this feature,
touch the Settings icon on the infotainment
home page. Select“Vehicle”to display the
list of available options and select “Collision/
Detection Systems”.
Turn off Park Assist when towing a trailer.
To turn the “Rear Camera Park Assist
Symbols” on or off, touch the Settings icon
on the infotainment home page. Select
“Vehicle” to display the list of available
options and select “Collision/Detection
Systems”.
Rear Cross Traffic Alert (RCTA)
System
If equipped, Rear Cross Traffic Alert (RCTA)
displays a red warning triangle with a left
or right pointing arrow on the infotainment
display to warn of traffic coming from the
left or right. This system detects objects
coming from up to 20 m (65 ft) from the left
or right side of the vehicle. When an object
is detected, either three beeps sound from
the left or right or three Safety Alert Seat pulses occur on the left or right side,
depending on the direction of the detected
vehicle.
Driving With a Trailer
Use caution while backing up when towing
a trailer. The RCTA feature is automatically
disabled when a trailer is attached to the
vehicle.
Turning the Features On or Off
The
Xbutton on the center stack is used
to turn on or off the Rear Park Assist (RPA),
and Backing Warning and Reverse Automatic
Braking (RAB) systems at the same time.
The indicator light next to the button comes
on when the features are on and turns off
when the features have been disabled.
Turn off RPA, RCTA, and RAB when towing a
trailer.
RCTA can be turned on or off using the
infotainment system. To view available
settings from the infotainment screen, touch
Settings > Vehicle > Collision/Detection
Systems.
Assistance Systems for Driving
If equipped, when driving the vehicle in a
forward gear, Forward Collision Alert (FCA),
Lane Keep Assist (LKA), Lane Departure
Warning (LDW), Side Blind Zone Alert (SBZA),
Lane Change Alert (LCA), and/or the
Automatic Emergency Braking (AEB) can help
to avoid a crash or reduce crash damage.
Forward Collision Alert (FCA)
System
If equipped, the FCA system may help to
avoid or reduce the harm caused by
front-end crashes. When approaching a
vehicle ahead too quickly, FCA provides a
red flashing alert on the windshield and
rapidly beeps or pulses the driver seat. FCA
also lights an amber visual alert if following
another vehicle much too closely.
FCA detects vehicles within a distance of
approximately 60 m (197 ft) and operates at
speeds above 8 km/h (5 mph).