GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
218 Driving and Operating
The vehicle will switch from accessory mode
to off after five minutes to prevent battery
rundown.
ON/RUN/START (Green Indicator Light) :This
mode is for driving and starting. With the
vehicle off, and the brake pedal applied,
pressing ENGINE START/STOP button once
will turn the ignition on. Once engine
cranking begins, release the button. Engine
cranking will continue until the engine
starts. See Starting the Engine 0218.
Service Mode
This power mode is available for service and
diagnostics, and to verify the proper
operation of the malfunction indicator lamp
as may be required for emission inspection
purposes. With the vehicle off, and the
brake pedal not applied, pressing and
holding the ENGINE START/STOP button for
more than five seconds will place the vehicle
in Service Mode. The instruments and audio
systems will operate as they do when the
vehicle is on, but the vehicle will not be able
to be driven. The engine will not start in
Service Mode. Press the ENGINE START/STOP
button again to turn the vehicle off.Starting the Engine
If the vehicle has a diesel engine, see the
Duramax diesel supplement.
Caution
If you add electrical parts or accessories,
you could change the way the engine
operates. Any resulting damage would
not be covered by the vehicle warranty.
See Add-On Electrical Equipment 0306.
Move the shift lever to P (Park) or
N (Neutral). To restart the engine when the
vehicle is already moving, use
N (Neutral) only.
Caution
Do not try to shift to P (Park) if the
vehicle is moving. If you do, you could
damage the transmission. Shift to P (Park)
only when the vehicle is stopped.
Starting Procedure
1. The remote key must be in the vehicle. Press ENGINE START/STOP with the brake
pedal applied. When the engine begins
cranking, let go of the button. The driver may observe a minor, and
temporary, brake pedal kickback when
starting the vehicle. This is normal.
The idle speed will go down as the
engine gets warm. Do not race the
engine immediately after starting it.
Operate the engine and transmission
gently to allow the oil to warm up and
lubricate all moving parts.
When the low fuel warning light is on
and the FUEL LEVEL LOW message is
displayed in the Driver Information
Center (DIC), press ENGINE START/STOP
to continue engine cranking.
Caution
Cranking the engine for long periods of
time, by returning the ignition to the
START position immediately after
cranking has ended, can overheat and
damage the cranking motor, and drain
the battery. Wait at least 15 seconds
between each try, to let the cranking
motor cool down.
2. If the engine does not start after five to 10 seconds, especially in very cold
weather (below −18 °C or 0 °F), it could
be flooded with too much gasoline. Try
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
Driving and Operating 221
Warning (Continued)
roll, even if the shift lever is in P (Park).
Be sure the transfer case is in a drive
gear. If towing a trailer, seeDriving
Characteristics and Towing Tips 0276.
1. Hold the brake pedal down, then set the parking brake. See Electric Parking Brake
0 234.
2. Move the shift lever into P (Park) by pulling the shift lever toward you and
moving it up as far as it will go.
3. Be sure the transfer case, if equipped, is in a drive gear, not in N (Neutral).
4. Turn the vehicle off.
5. Take the remote key with you.
Leaving the Vehicle with the Engine
Running
{Warning
It can be dangerous to leave the vehicle
with the engine running. The vehicle
could move suddenly if the shift lever is
not fully in P (Park) with the parking
brake firmly set. (Continued)
Warning (Continued)
If you have four-wheel drive and the
transfer case is in N (Neutral), the vehicle
will be free to roll, even if the shift lever
is in P (Park). So be sure the transfer case
is in a drive gear–not in N (Neutral).
And, if you leave the vehicle with the
engine running, it could overheat and
even catch fire. You or others could be
injured. Do not leave the vehicle with the
engine running unless you have to.
If you have to leave the vehicle with the
engine running, be sure the vehicle is in
P (Park) and the parking brake is firmly set
before you leave it. After moving the shift
lever into P (Park), hold the regular brake
pedal down. Then, see if you can move the
shift lever away from P (Park) without first
pulling it toward you. If you can, it means
that the shift lever was not fully locked into
P (Park).
Torque Lock
If you are parking on a hill and you do not
shift the transmission into P (Park) properly,
the weight of the vehicle may put too much
force on the parking pawl in the transmission. You may find it difficult to pull
the shift lever out of P (Park). This is called
torque lock. To prevent torque lock, set the
parking brake and then shift into P (Park)
properly before you leave the driver seat.
When you are ready to drive, move the
shift lever out of P (Park) before you release
the parking brake.
If torque lock does occur, you may need to
have another vehicle push yours a little
uphill to take some of the pressure from the
parking pawl in the transmission. You will
then be able to pull the shift lever out of
P (Park).
Shifting out of Park
This vehicle is equipped with an electronic
shift lock release system. The system is
designed to prevent movement of the shift
lever out of P (Park), unless the brake pedal
is applied and the ignition is on or in
Service Mode.
The shift lock release is always functional
except in the case of an uncharged or low
voltage
–less than 9 volt –battery.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/13/22
222 Driving and Operating
If the vehicle has an uncharged or low
voltage battery, try charging or jump
starting the battery. SeeJump Starting -
North America 0376.
To shift out of P (Park): 1. Apply the brake pedal.
2. Release the parking brake if it is applied. See Electric Parking Brake 0234.
3. Pull the shift lever toward you, then move it to the desired position, and
release.
If the vehicle still cannot be shifted out of
P (Park): 1. Ease the pressure on, or release the shift lever.
2. While holding the brake pedal, push the shift lever all the way into P (Park).
3. Pull the shift lever toward you, then move it to the desired position, and
release.
If equipped, the Buckle to Drive feature may
prevent shifting from P (Park). See Buckle To
Drive 058.
If there is still a problem shifting, have the
vehicle serviced soon.Parking over Things That Burn
{Warning
Things that can burn could touch hot
exhaust parts under the vehicle and
ignite. Do not park over papers, leaves,
dry grass, or other things that can burn.
Extended Parking
It is best not to park with the vehicle
running. If the vehicle is left running, be
sure it will not move and there is adequate
ventilation.
See Shifting Into Park 0220 and
Engine Exhaust 0222.
If the vehicle is left parked and running with
the remote key outside the vehicle, it will
continue to run for up to 15 minutes.
If the vehicle is left parked and running with
the remote key inside the vehicle, it will
continue to run for up to 30 minutes.
The vehicle could turn off sooner if it is
parked on a hill, due to lack of
available fuel.
The timer will reset if the vehicle is taken
out of P (Park) while it is running. When the vehicle was produced, it came
with the auto-shutdown feature enabled.
If you are not the primary owner of your
vehicle, please note that this feature may
have been disabled by a previous owner.
The vehicle owners can have this feature
re-enabled at owner cost at any GM service
center.
Engine Exhaust
{
Warning
Engine exhaust contains carbon monoxide
(CO), which cannot be seen or smelled.
Exposure to CO can cause
unconsciousness and even death.
Exhaust may enter the vehicle if:
.The vehicle idles in areas with poor
ventilation (parking garages, tunnels,
deep snow that may block underbody
airflow or tail pipes).
.The exhaust smells or sounds strange
or different.
.The exhaust system leaks due to
corrosion or damage. (Continued)
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
328 Vehicle Care
Extended Storage: Remove the black,
negative (−) cable from the battery or use a
battery trickle charger.
Negative Battery Cable Disconnection
{Warning
Before disconnecting the negative battery
cable, turn off all features, turn the
ignition off, and remove the key,
if equipped, from the vehicle. If this is
not done, you or others could be injured,
and the vehicle could be damaged.
Caution
If the battery is disconnected with the
ignition on or the vehicle in Retained
Accessory Power (RAP), the OnStar
back-up battery will be permanently
discharged and will need to be replaced.
1. Make sure the lamps, features, and accessories are turned off.
2. Turn the vehicle off and remove the key, if equipped.
1. Loosen the negative battery cable nut (1).
2. Remove the negative battery cableclamp (2) from the negative battery post.
3. Cover the negative battery cable clamp, and negative battery post with a
non-conductive material to prevent any
contact with the negative battery cable.
Negative Battery Cable Reconnection
Caution
When reconnecting the battery:
.Use the original nut from the vehicle
to secure the negative battery cable.
Do not use a different nut. If you
need a replacement nut, see your
dealer.
.Tighten the nut with a hand tool. Do
not use an impact wrench or power
tools to tighten the nut.
The vehicle could be damaged if these
guidelines are not followed.
Caution
Do not use paints, lubricants, or corrosion
inhibitors on the nut that secures the
negative battery cable to the vehicle. This
could damage the vehicle.
1. Install the negative battery cable clamp to the negative battery post.
2. Tighten the negative battery cable nut.
3. Turn the vehicle on.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
382 Vehicle Care
{Warning
To avoid death, serious injury,
or property damage, before dinghy
towing the vehicle, always disconnect and
secure the negative battery cable and
cover the negative battery post and cable
with a non-conductive material. If the
battery is left connected or the battery
cable contacts the post, the Electric
Parking Brake may activate during
towing, which could cause a crash.
8. Disconnect the negative (–) battery cable. See “Negative Battery Cable
Disconnection” inBattery - North
America 0327.
9. Shift the transmission to P (Park).
Caution
If the steering column is locked, vehicle
damage may occur.
10. Move the steering wheel to make sure the steering column is unlocked.
11. Keep the remote key outside of the vehicle and manually lock the doors.
Access the vehicle by using the key in
the door lock. See Door Locks022. Disconnecting the Towed Vehicle
Before disconnecting from the tow vehicle:
1. Park on a level surface. Secure the vehicle with wheel blocks.
2. Reconnect the negative (–) battery. See Battery - North America 0327.
3. Turn on the vehicle. With your foot off the brake pedal, press and hold ENGINE
START/STOP for five seconds until the
green light comes on in the button. See
Ignition Positions 0216.
4. Set the parking brake. See Electric
Parking Brake 0234.
5. Disconnect from the tow vehicle.
6. Shift the transmission to N (Neutral).
7. Shift the transfer case to 2
m(Two-Wheel
Drive High). When the shift to 2
m
(Two-Wheel Drive High) is complete, the
light in the instrument cluster will stop
flashing and stay lit. See
Four-Wheel-Drive Light 0125.
8. Start the engine. Check that the vehicle is in 2
m(Two-Wheel Drive High) by
starting the engine and shifting the
transmission to D (Drive) and then to
R (Reverse). There should be movement
of the vehicle while shifting. 9. Shift the transmission to P (Park) and
turn off the vehicle.
10. Release the parking brake and remove the wheel blocks.
11. Reset any lost presets.
The outside temperature display will
default to 0 °C (32 °F) but will reset with
normal usage.
Dolly Towing
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
418 OnStar
Or
.Give OnStar Turn-by-Turn Navigation voice
commands.
.Obtain and customize the Wi-Fi hotspot
name or SSID and password, if equipped.
Press
Qto connect to an Advisor to:
.Verify account information or update
contact information.
.Get driving directions.
.Receive a Diagnostic check of the vehicle's
key operating systems.
.Receive Roadside Assistance.
.Manage Wi-Fi Settings, if equipped.
Press
>to get a priority connection to an
OnStar Advisor available 24/7 to:
.Get help for an emergency.
.Be a Good Samaritan or respond to an
AMBER Alert.
.Get assistance in severe weather or other
crisis situations and find evacuation
routes.
OnStar Services
Emergency
Emergency Services require an active safety
and security plan. With Automatic Crash
Response, built-in sensors can automatically
alert a specially trained OnStar Advisor who
is immediately connected in to the vehicle
to help.
Press
>for a priority connection to an
OnStar Advisor who can contact emergency
service providers, direct them to your exact
location, and relay important information.
With OnStar Crisis Assist, specially trained
Advisors are available 24 hours a day, 7 days
a week, to provide a central point of
contact, assistance, and information during a
crisis.
With Roadside Assistance, Advisors can
locate a nearby service provider to help with
a flat tire, a battery jump, or an empty
gas tank.
Security
If equipped, OnStar provides these services:
.With Stolen Vehicle Assistance, OnStar
Advisors can use GPS to pinpoint the
vehicle and help authorities quickly
recover it.
.With Remote Ignition Block, if equipped,
OnStar can block the vehicle from being
restarted.
.With Stolen Vehicle Slowdown,
if equipped, OnStar can work with law
enforcement to gradually slow the
vehicle down.
Theft Alarm Notification
If equipped, if the doors are locked and the
vehicle alarm sounds, a notification by text,
e-mail, or phone call will be sent. If the
vehicle is stolen, an OnStar Advisor can work
with authorities to recover the vehicle.
GMC Sierra/Sierra Denali 2500 HD/3500 HD Owner Manual (GMNA-
Localizing-U.S./Canada-16908340) - 2024 - CRC - 12/7/22
Index 433
ParkingBrake and P (Park) Mechanism
Check . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 331
Extended . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 222
Over Things That Burn . . . . . . . . . . . . . . . . . 222
Parking or Backing Assistance Systems . . . . . . . . . . . . . . . . . . . . 253
Passenger Airbag Status Indicator . . . . . . . . . . . . . . . . . 121
Compartment Air Filter . . . . . . . . . . . . . . . . 196
Sensing System . . . . . . . . . . . . . . . . . . . . . . . . . 69
Pedestrian Ahead Indicator . . . . . . . . . . . . . . 126
Perchlorate Materials Requirements, California . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 310
Phone Apple CarPlay and
Android Auto . . . . . . . . . . . . . . . . . . . . 177, 179
Bluetooth . . . . . . . . . . . . . . . . . . . . . . 170, 171, 174
Pickup Conversion to Chassis Cab . . . . . . . . 308
Port USB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Positioning Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 167
Power Assist Steps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 31
Door Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 23
Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 35
Outlets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 107 Power (cont'd)
Protection, Battery . . . . . . . . . . . . . . . . . . . . . 152
Retained Accessory (RAP) . . . . . . . . . . . . . . 220
Seat Adjustment . . . . . . . . . . . . . . . . . . . . . . . . 49
Steering Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 323
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42
Pregnancy, Using Seat Belts . . . . . . . . . . . . . . 63
Privacy
Vehicle Data Recording . . . . . . . . . . . . . . . . 415
Problems with Route Guidance . . . . . . . . . . 168
Program Courtesy Transportation . . . . . . . . . . . . . . . 410
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . . . 272
Proposition 65 Warning California . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1
Proposition 65 Warning, California . . . . . . . 376
Publication Ordering Information . . . . . . . . .413
R
Radiator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 319
Radio AM-FM Radio . . . . . . . . . . . . . . . . . . . . . . 159, 161
Frequency Statement . . . . . . . . . . . . . . . . . . 413
Reception . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Satellite . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 162
Reading Lamps . . . . . . . . . . . . . . . . . . . . . . . . . . . 151 Rear
Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Camera Mirror . . . . . . . . . . . . . . . . . . . . . . . . . . 38
Heated Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Locking Axle . . . . . . . . . . . . . . . . . . . . . . . . . . . 239
Seats . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 55
Storage . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 100
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 44
Rearview Mirror Truck Bed Camera . . . . . . . . . . . . . . . . . . . . . . 41
Rearview Mirrors . . . . . . . . . . . . . . . . . . . . . . . . . 38
Automatic Dimming . . . . . . . . . . . . . . . . . . . . 38
Reclining Seatbacks . . . . . . . . . . . . . . . . . . . . . . . 49
Recognition Voice . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 168
Recommended
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 272
Recommended Fluids and Lubricants . . . . . 398
Records Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . 400
Recreational Vehicle Towing . . . . . . . . . . . . . 380
Reimbursement Program, GM
Mobility . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 408
Remote Key . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Key Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . 15
Vehicle Start . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21