2024 GMC SIERRA DENALI climate control

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
196 Climate Controls
Afterblow Feature
If equipped, under certain conditions, the
fan may stay on or may turn on and off
several times after you turn off and lock the
vehicle. This is normal.
Air Vents
Use the sliding knobs on the center and side
air vents to change the direction of the
airflow.
Air vents blow warm air on the side
windows in cold weather. If Floor, Defog,
or Defrost modes are selected, a small
amount of air will come from the vents
closest to the window.
To close the front A/C vents, move the
sliding knobs to the full down position for
vertical slats or away from you for
horizontal slats.
To close the rear A/C vents, move the
sliding knobs to the full inboard position.
Operation Tips
.Clear away any ice, snow, or leaves from
air inlets at the base of the windshield
that could block airflow.
.Clear snow off the hood to improve
visibility and help decrease moisture
drawn into the vehicle.
.Keep the path under the front seats clear
of objects to help circulate the air inside
of the vehicle more effectively.
.Use of non-GM approved hood deflectors
can adversely affect system performance.
Check with your dealer before adding
equipment to the outside of the vehicle.
.Do not attach any devices to the air vent
slats. Doing so restricts airflow and may
cause damage to the air vents.
Maintenance
Passenger Compartment Air Filter
The filter reduces the dust, pollen, and other
airborne irritants from outside air that is
pulled into the vehicle.
The filter should be replaced as part of
routine scheduled maintenance. See
Maintenance Schedule0394. To find out
what type of filter to use, see Maintenance
Replacement Parts 0399.
1. Open the lower glove box door
completely.
2. Push the dampener arm to the left untilit releases the glove box.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Climate Controls 197
3. Press the sides of the glove box doorinward and rotate the door downward to
remove.
4. Pull lever on left side of the filter doorand slide left, then remove the door.
Remove the old filter.
5. Install the new air filter.
6. Reinstall the filter door.
7. Reverse the steps to reinstall the glove box.
See your dealer if additional assistance is
needed.
Service
All vehicles have a label underhood that
identifies the refrigerant used in the vehicle.
The refrigerant system should only be
serviced by trained and certified technicians.
The air conditioning evaporator should never
be repaired or replaced by one from a
salvage vehicle. It should only be replaced
by a new evaporator to ensure proper and
safe operation.
During service, all refrigerants should be
reclaimed with proper equipment. Venting
refrigerants directly to the atmosphere is
harmful to the environment and may also
create unsafe conditions based on
inhalation, combustion, frostbite, or other
health-based concerns. The air conditioning system requires periodic
maintenance. See
Maintenance Schedule
0 394.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 199
Trailer Towing
General Towing Information . . . . . . . . . . . 276
Driving Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . . . . . 276
Trailer Towing . . . . . . . . . . . . . . . . . . . . . . . . 280
Towing Equipment . . . . . . . . . . . . . . . . . . . . 284
Trailer Sway Control (TSC) . . . . . . . . . . . . . 294
Trailering App . . . . . . . . . . . . . . . . . . . . . . . . . 296
Conversions and Add-Ons
Add-On Electrical Equipment . . . . . . . . . . 306
Adding a Snow Plow or Similar Equipment . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Pickup Conversion to Chassis Cab . . . . . 308
Driving Information
Driving for Better Fuel Economy
Driving habits can affect fuel mileage. Here
are some driving tips to get the best fuel
economy possible:
.Set the climate controls to the desired
temperature after the engine is started,
or turn them off when not required.
.Avoid fast starts and accelerate smoothly.
.Brake gradually and avoid abrupt stops.
.Avoid idling the engine for long periods
of time.
.When road and weather conditions are
appropriate, use cruise control.
.Always follow posted speed limits or
drive more slowly when conditions
require.
.Keep vehicle tires properly inflated.
.Combine several trips into a single trip.
.Replace the vehicle's tires with the same
TPC Spec number molded into the tire's
sidewall near the size.
.Follow recommended scheduled
maintenance.
Distracted Driving
Distraction comes in many forms and can
take your focus from the task of driving.
Exercise good judgment and do not let other
activities divert your attention away from
the road. Many local governments have
enacted laws regarding driver distraction.
Become familiar with the local laws in
your area.
To avoid distracted driving, keep your eyes
on the road, keep your hands on the
steering wheel, and focus your attention on
driving.
.Do not use a phone in demanding driving
situations. Use a hands-free method to
place or receive necessary phone calls.
.Watch the road. Do not read, take notes,
or look up information on phones or
other electronic devices.
.Designate a front seat passenger to
handle potential distractions.
.Become familiar with vehicle features
before driving, such as programming
favorite radio stations and adjusting
climate control and seat settings. Program
all trip information into any navigation
device prior to driving.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
208 Driving and Operating
For Slippery Road Driving:
.Accelerate gently. Accelerating too quickly
causes the wheels to spin and makes the
surface under the tires slick.
.Turn on Traction Control. SeeTraction
Control/Electronic Stability Control 0236.
.The Antilock Brake System (ABS) improves
vehicle stability during hard stops, but
the brakes should be applied sooner than
when on dry pavement. See Antilock
Brake System (ABS) 0233.
.Allow greater following distance and
watch for slippery spots. Icy patches can
occur on otherwise clear roads in shaded
areas. The surface of a curve or an
overpass can remain icy when the
surrounding roads are clear. Avoid sudden
steering maneuvers and braking while
on ice.
.Turn off cruise control.
Cold Weather Mode
In very low temperatures, a cold weather
message may display on the Driver
Information Center (DIC). The engine speed,
transmission shift patterns, and cabin fan
speed may operate differently to enable the vehicle to warm up quicker. You can
manually override the cabin fan speed in
cold weather mode.
Blizzard Conditions
Stop the vehicle in a safe place and signal
for help. Stay with the vehicle unless there
is help nearby. If possible, use Roadside
Assistance. See
Roadside Assistance Program
0 408. To get help and keep everyone in
the vehicle safe:
.Turn on the hazard warning flashers.
.Tie a red cloth to an outside mirror.
{Warning
Snow can trap engine exhaust under the
vehicle. This may cause exhaust gases to
get inside. Engine exhaust contains
carbon monoxide (CO), which cannot be
seen or smelled. It can cause
unconsciousness and even death.
If the vehicle is stuck in snow:
.Clear snow from the base of the
vehicle, especially any blocking the
exhaust pipe.
(Continued)
Warning (Continued)
.Open a window about 5 cm (2 in) on
the vehicle side that is away from the
wind, to bring in fresh air.
.Fully open the air outlets on or under
the instrument panel.
.Adjust the climate control system to
circulate the air inside the vehicle and
set the fan speed to the highest
setting. See“Climate Control Systems.”
For more information about CO, see
Engine Exhaust 0222.
To save fuel, run the engine for short
periods to warm the vehicle and then shut
the engine off and partially close the
window. Moving about to keep warm also
helps.
If it takes time for help to arrive, when
running the engine, push the accelerator
pedal slightly so the engine runs faster than
the idle speed. This keeps the battery
charged to restart the vehicle and to signal
for help with the headlamps. Do this as
little as possible, to save fuel.

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 - 12/7/22
362 Vehicle Care
times as well on the government course
as a tire graded 100. The relative
performance of tires depends upon the
actual conditions of their use, however,
and may depart significantly from the
norm due to variations in driving habits,
service practices and differences in road
characteristics and climate.
Traction
The traction grades, from highest to
lowest, are AA, A, B, and C. Those
grades represent the tire's ability to
stop on wet pavement as measured
under controlled conditions on specified
government test surfaces of asphalt and
concrete. A tire marked C may have
poor traction performance. Warning:
The traction grade assigned to this tire
is based on straight-ahead braking
traction tests, and does not include
acceleration, cornering, hydroplaning,
or peak traction characteristics.Temperature
The temperature grades are A (the
highest), B, and C, representing the
tire's resistance to the generation of
heat and its ability to dissipate heat
when tested under controlled conditions
on a specified indoor laboratory test
wheel. Sustained high temperature can
cause the material of the tire to
degenerate and reduce tire life, and
excessive temperature can lead to
sudden tire failure. The grade C
corresponds to a level of performance
which all passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B and A
represent higher levels of performance
on the laboratory test wheel than the
minimum required by law. Warning:
The temperature grade for this tire is
established for a tire that is properly
inflated and not overloaded. Excessive
speed, underinflation, or excessive
loading, either separately or in
combination, can cause heat buildup
and possible tire failure.Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider an
alignment check if there is unusual tire wear
or the vehicle is significantly pulling to one
side or the other. Some slight pull to the
left or right, depending on the crown of the
road and/or other road surface variations
such as troughs or ruts, is normal. If the
vehicle is vibrating when driving on a
smooth road, the tires and wheels may
need to be rebalanced. See your dealer for
proper diagnosis.
Wheel Replacement
Replace any wheel that is bent, cracked,
or badly rusted or corroded. If wheel nuts
keep coming loose, the wheel, wheel bolts,
and wheel nuts should be replaced. If the
wheel leaks air, replace it. Some aluminum
wheels can be repaired. See your dealer if
any of these conditions exist.

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
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

GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
428 Index
Data Collection (cont'd)OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 416
Data Recorders, Event . . . . . . . . . . . . . . . . . . . .415
Daytime Running Lamps (DRL) . . . . . . . . . . . .145
Defensive Driving . . . . . . . . . . . . . . . . . . . . . . . . 200
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . . . .23
Destination . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 166
Diagnostics Connected Services . . . . . . . . . . . . . . . . . . . . 424
Disabled Vehicle Transporting . . . . . . . . . . . . . . . . . . . . . . . . . . . 379
Distracted
Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 199
Distracted Driving . . . . . . . . . . . . . . . . . . . . . . . . 199
Dome Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 150
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 131
Delayed Locking . . . . . . . . . . . . . . . . . . . . . . . . 23
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
Power Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Drive Belt Routing, Engine . . . . . . . . . . . . . . . 404
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . . . . . . . . . . 329
Driver Assistance Systems, Advanced . . . . . . . . . 252
Information Center (DIC) . . . . . . . . . . . 131, 133
Mode Control . . . . . . . . . . . . . . . . . . . . . . . . . . 238
Mode Control Light . . . . . . . . . . . . . . . . . . . . 128 Driver (cont'd)
Teen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 185
Driving Assistance Systems . . . . . . . . . . . . . . . . . . . . 263
Better Fuel Economy . . . . . . . . . . . . . . . . . . . 199
Characteristics and Towing Tips . . . . . . . . 276
Defensive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
Hill and Mountain Roads . . . . . . . . . . . . . . 207
If the Vehicle is Stuck . . . . . . . . . . . . . . . . . 209
Impaired . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 200
Loss of Control . . . . . . . . . . . . . . . . . . . . . . . . 202
Off-Road . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 203
Off-Road Recovery . . . . . . . . . . . . . . . . . . . . . 202
Vehicle Load Limits . . . . . . . . . . . . . . . . . . . . 210
Wet Roads . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 206
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Dual Automatic Climate Control System . . . . 193
E
E85 or FlexFuel . . . . . . . . . . . . . . . . . . . . . . . . . . 272
ElectricParking Brake . . . . . . . . . . . . . . . . . . . . . . . . . . 234
Parking Brake Light . . . . . . . . . . . . . . . . . . . . 124
Electrical Equipment, Add-On . . . . . . . . . . . . . . . . . . . . 306
System Overload . . . . . . . . . . . . . . . . . . . . . . 335 Electrical System
Engine Compartment Fuse Block . . . . . . . 337
Fuses and Circuit Breakers . . . . . . . . . . . . . 337
Instrument Panel Fuse Block . . . . . . 341, 342
Electronic Stability Control (ESC) Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 127
Emergency
OnStar . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 418
Engine Air Cleaner/Filter . . . . . . . . . . . . . . . . . . . . . . 318
Air Filter Life System . . . . . . . . . . . . . . . . . . . 317
Check Light (Malfunction Indicator) . . . . 122
Compartment Overview . . . . . . . . . . . . . . . . 313
Coolant Temperature Gauge . . . . . . . . . . . . 118
Coolant Temperature WarningLight . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 128
Cooling System . . . . . . . . . . . . . . . . . . . . . . . . 319
Drive Belt Routing . . . . . . . . . . . . . . . . . . . . . 404
Exhaust . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Heater . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 219
Oil Life System . . . . . . . . . . . . . . . . . . . . . . . . 316
Oil Pressure Gauge . . . . . . . . . . . . . . . . . . . . . 117
Oil Pressure Light . . . . . . . . . . . . . . . . . . . . . . 129
Overheated Protection Operating Mode . . . . . . . . . . . . . . . . . . . . . 323
Overheating . . . . . . . . . . . . . . . . . . . . . . . . . . . 321
Power Messages . . . . . . . . . . . . . . . . . . . . . . . 139