2024 GMC SIERRA change time

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 263
Assist on again, select On in 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.
Turn off Park Assist when towing a trailer.
To turn the RPA symbols on or off, from the
infotainment screen, touch Settings >
Vehicle > Comfort and Convenience > Rear
Park Assist Symbols.
Rear Cross Traffic Alert (RCTA)
System
If equipped, when the vehicle is shifted into
R (Reverse), RCTA shows 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.Use caution while backing up when towing
a trailer, as the RCTA detection zones that
extend out from the back of the vehicle do
not move further back when a trailer is
towed.
RCTA is disabled when the trailer connection
status is displayed.
RCTA can be turned off. 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),
Front Pedestrian Braking, (FPB), 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 ared flashing alert on the windshield and
rapidly beeps or pulses the drivers seat (if
equipped). 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).
{Warning
FCA is a warning system and does not
apply the brakes. When approaching a
slower-moving or stopped vehicle ahead
too rapidly, or when following a vehicle
too closely, FCA may not provide a
warning with enough time to help avoid
a crash. It also may not provide any
warning at all. FCA does not warn of
pedestrians, animals, signs, guardrails,
bridges, construction barrels, or other
objects. Be ready to take action and
apply the brakes. See
Defensive Driving
0 200.
FCA can be disabled. To view available
settings from the infotainment screen, touch
Settings > Vehicle > Collision/Detection
Systems.

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-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 271
direction of lane departure, or if LDW
detects that you are accelerating, braking or
actively steering.
{Warning
The LDW system does not steer the
vehicle. The LDW system may not:
.Provide enough time to avoid a crash.
.Detect lane markings under poor
weather or visibility conditions. This
can occur if the windshield or
headlamps are blocked by dirt, snow,
or ice; if they are not in proper
condition; or if the sun shines directly
into the camera.
.Detect road edges.
.Detect lanes on winding or hilly roads.
If LDW only detects lane markings on one
side of the road, it will only warn you
when departing the lane on the side
where it has detected a lane marking.
Always keep your attention on the road
and maintain proper vehicle position
within the lane, or vehicle damage,
injury, or death could occur. Always keep (Continued)
Warning (Continued)
the windshield, headlamps, and camera
sensors clean and in good repair. Do not
use LDW in bad weather conditions.
How the System Works
LDW utilizes a camera sensor installed on
the windshield ahead of the rearview mirror
to detect lane markings.
To turn LDW on and off, press
@on the
center stack. The control indicator will light
when LDW is on.
BaseUplevel
When LDW is on,
@ornis green if
LDW is available to warn of a lane
departure. If the vehicle crosses a detected
lane marking without using the turn signal
in that direction,
@ornchanges to
amber and flashes. Additionally, there will
be three beeps, on the right or left, depending on the lane departure direction.
LDW will not alert if the turn signal is active
in the direction of lane departure or if LDW
detects that you are accelerating, braking or
actively steering.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine clean,
reduce engine deposits, and maintain
optimal vehicle performance. Look for the
TOP TIER Logo or see www.toptiergas.com
for a list of TOP TIER Detergent Gasoline
marketers and applicable countries.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
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 - 12/13/22
280 Driving and Operating
5. Gradually release the brake pedal toallow the chocks to absorb the load of
the trailer.
6. Reapply the brake pedal. Then, apply the parking brake and shift into P (Park).
7. Release the brake pedal.
Pulling the Trailer from the Water
To pull the trailer out of the water: 1. Press and hold the brake pedal.
2. Start the engine and shift into gear.
3. Release the parking brake.
4. Let up on the brake pedal.
5. Drive slowly until the tires are clear of the chocks.
6. Stop and have someone pick up and store the chocks.
7. Slowly pull the trailer from the water.
8. Once the vehicle and trailer have been driven from the sloped part of the boat
ramp, the vehicle can be shifted from
four-wheel-drive high. Shift into the drive
mode that is appropriate for the road
conditions.Caution
If the vehicle tires begin to spin and the
vehicle begins to slide toward the water,
remove your foot from the accelerator
pedal and apply the brake pedal. Seek
help to have the vehicle towed up
the ramp.
Maintenance when Trailer Towing
The vehicle needs service more often when
used to tow trailers. See Maintenance
Schedule 0394. It is especially important to
check the engine oil, axle lubricant, belts,
cooling system, and brake system before
and during each trip.
Check periodically to see that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily
overheat during severe operating conditions.
See Engine Overheating 0321.
Trailer Towing
If equipped with a diesel engine, see the
Duramax diesel supplement.
Caution
Towing a trailer improperly can damage
the vehicle and result in costly repairs
not covered by the vehicle warranty. To
tow a trailer correctly, follow the
directions in this section and see your
dealer for important information about
towing a trailer with the vehicle.
Trailering is different than just driving the
vehicle by itself. Trailering means changes in
handling, acceleration, braking, and
durability. Successful, safe trailering takes
correct equipment, and it has to be used
properly.
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 pulling a
trailer.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
292 Driving and Operating
Warning (Continued)
injury, death, or property damage. Only
use the ITBC system with electric or
electric over hydraulic trailer brake
systems.
Trailer Brake Control Panel
1. Manual Trailer Brake Apply Lever
2. Trailer Symbol
3. Trailer Gain Adjustment Buttons
The trailer symbol on the control panel will
light amber when a trailer with electric
brakes is connected.The ITBC control panel is on the center stack
or center console. See
Instrument Panel
Overview 05. The control panel allows
adjustment to the amount of output,
referred to as Trailer Gain, available to the
trailer brakes and allows manual application
of the trailer brakes. Use the ITBC control
panel and the DIC trailer brake display page
to adjust and display power output to the
trailer brakes.
Trailer Brake DIC Display Page
The ITBC display page indicates:
.Trailer Gain setting
.Output to the trailer brakes
.Trailer connection
.System operational status
To display:
.Scroll through the DIC menu pages
.Press a Trailer Gain (+) or (−) button
.Activate the Manual Trailer Brake Apply
Lever
TRAILER GAIN: Press a Trailer Gain button to
recall the current Trailer Gain setting. Each
press and release of the gain buttons will
then change the Trailer Gain setting. Press
the Trailer Gain (+) or (-) to adjust. Press and
hold to continuously adjust the Trailer Gain. To turn the output to the trailer off, adjust
the Trailer Gain setting to 0.0. This setting
can be adjusted from 0.0 to 10.0 with a
trailer connected or disconnected.
TRAILER OUTPUT: This displays anytime a
trailer with electric brakes is connected.
Output to the trailer brakes is based on the
amount of vehicle braking present and
relative to the Trailer Gain setting. Output is
displayed from 0 to 100% for each gain
setting.
The Trailer Output will indicate
“- - - - - -”on
the Trailer Brake Display Page whenever the
following occur:
.No trailer is connected.
.A trailer without electric brakes is
connected. No DIC message displays.
.A trailer with electric brakes has become
disconnected. A CHECK TRAILER WIRING
message displays on the DIC.
.There is a fault present in the wiring to
the trailer brakes. A CHECK TRAILER
WIRING message displays on the DIC.
.The ITBC system is not working due to a
fault. A SERVICE TRAILER BRAKE SYSTEM
message displays in the DIC.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 293
Manual Trailer Brake Apply Lever
Slide this lever to apply the trailer’s electric
brakes independent of the vehicle’s brakes.
Use this lever to adjust the Trailer Gain to
achieve proper power output to the trailer
brakes. Under certain circumstances, this
lever can also be used to apply additional
trailer braking. The trailer and vehicle brake
lamps will come on when either the vehicle
brakes or trailer brakes are applied and
properly connected.
Trailer Gain Adjustment Procedure
Trailer Gain should be set for a specific
trailering condition and it must be
readjusted anytime vehicle loading, trailer
loading, or road surface conditions change.
{Warning
Trailer brakes that are over-gained or
under-gained may not stop the vehicle
and the trailer as intended and can result
in a crash. Always follow the instructions
to set the Trailer Gain for the proper
trailer stopping performance.To adjust Trailer Gain for each towing
condition:
1. Drive the vehicle with the trailer attached on a level road surface
representative of the towing condition
and free of traffic at about 32–40 km/h
(20–25 mph) and fully apply the Manual
Trailer Brake Apply Lever.
Adjusting Trailer Gain at speeds lower
than 32–40 km/h (20–25 mph) may
result in an incorrect gain setting.
2. Adjust the Trailer Gain, using the Trailer Gain (+) or (−) adjustment buttons, to
just below the point of trailer wheel
lock-up, indicated by trailer wheel squeal
or tire smoke when a trailer wheel locks.
Trailer wheel lock-up may not occur if
towing a heavily loaded trailer. Adjust
the Trailer Gain to the highest allowable
setting for the towing condition.
3. Readjust Trailer Gain anytime vehicle loading, trailer loading, or road surface
conditions change or if trailer wheel
lock-up is noticed at any time while
towing.
Other ITBC-Related DIC Messages
TRAILER BRAKES CONNECTED: This message
will briefly display when a trailer with
electric brakes is first connected to the
vehicle. This message will automatically turn
off in about 10 seconds. This message can
be acknowledged before it automatically
turns off.
CHECK TRAILER WIRING: This message will
display if:
.The ITBC system first determines
connection to a trailer with electric brakes
and then the trailer harness becomes
disconnected from the vehicle.
.The disconnect occurs while the vehicle is
stationary, this message will
automatically turn off in about
30 seconds. This message will also turn
off if it is acknowledged or if the trailer
harness is reconnected.
.The disconnect occurs while the vehicle is
moving, this message will continue until
the vehicle is turned off. This message
will also turn off if it is acknowledged or
if the trailer harness is reconnected.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
302 Driving and Operating
tires were rotated or if the tire pressure
sensors in the tires were replaced for this
Trailer Profile. The vehicle will need to
relearn the tire sensors and their locations.
See“Trailer Tire Pressure Setup” previously
in this section.
Touch Edit Target Pressure to change the
recommended tire pressure for the trailer
tires. This will change the number at which
the vehicle displays alerts related to trailer
tire pressure.
Maintenance
Touch to view a list of maintenance
reminders for the Trailer Profile.
The Maintenance Status view displays
reminders for the Trailer Profile. Touch a
reminder to view, reset, delete, or edit it. Resetting a reminder will reset the time and
mileage values for the reminder. The
progress bar turns yellow when the
maintenance item reaches 90% complete.
The progress bar turns red when the
maintenance item reaches 100% complete.
Touch New Reminder to add a new
maintenance reminder.
Suggested reminders that were previously
set will not appear. Suggested reminders
that have not been set have empty boxes
next to them. The maximum number of
reminders is 50.
Maintenance Notifications
Touch Reset to reset time and mileage
values for the reminder.
Touch Remind Me Later to delay the
reminder.
If an Upcoming Alert (90%) is dismissed, it
will not appear again.
If a Maintenance Due Alert (100%) is
dismissed, it will appear when the vehicle is
turned off and back on again.
Always follow all of the maintenance
instructions that came with your trailer.
Cameras
This view shows a preview of the selected
camera view. Touch X to exit the preview.
Touch the camera icon to open the
camera app.
Checklist View
This view shows the recommended steps to
take before towing a trailer.