
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Climate Controls 243
Climate Controls
Climate Control Systems
Climate Control Systems (withHeater Only) . . . . . . . . . . . . . . . . 243
Climate Control Systems (with Air Conditioning) . . . . . . . . . . . . 245
Dual Automatic Climate Control System . . . . . . . . . . . . . 246
Air Vents
Air Vents . . . . . . . . . . . . . . . . . . . . . 250
Maintenance
Passenger Compartment AirFilter . . . . . . . . . . . . . . . . . . . . . . . . 250
Service . . . . . . . . . . . . . . . . . . . . . . . 251
Climate Control Systems
Climate Control Systems (with Heater Only)
With this system, the heating and ventilation can be controlled.
1. Fan Control
2. Air Recirculation
3. Air Delivery Mode Controls 4. Defrost
5. TEMP (Temperature Control)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
252 Driving and Operating
Driving and
Operating
Driving Information
Distracted Driving . . . . . . . . . . . . 253
Defensive Driving . . . . . . . . . . . . . 254
Drunk Driving . . . . . . . . . . . . . . . . . 254
Control of a Vehicle . . . . . . . . . . . 254
Braking . . . . . . . . . . . . . . . . . . . . . . . 254
Steering . . . . . . . . . . . . . . . . . . . . . . 255
Off-Road Recovery . . . . . . . . . . . 256
Loss of Control . . . . . . . . . . . . . . . 256
Off-Road Driving . . . . . . . . . . . . . 257
Driving on Wet Roads . . . . . . . . 261
Hill and Mountain Roads . . . . . 262
Winter Driving . . . . . . . . . . . . . . . . 263
If the Vehicle Is Stuck . . . . . . . . 264
Vehicle Load Limits . . . . . . . . . . . 265
Truck-Camper LoadingInformation . . . . . . . . . . . . . . . . . . 271
Starting and Operating
New Vehicle Break-In . . . . . . . . . 273
Adjustable Throttle and BrakePedal . . . . . . . . . . . . . . . . . . . . . . . 273
Ignition Positions . . . . . . . . . . . . . 274
Starting the Engine . . . . . . . . . . . 275
Fast Idle System . . . . . . . . . . . . . 276 Retained Accessory
Power (RAP) . . . . . . . . . . . . . . . . 277
Engine Coolant Heater . . . . . . . 278
Shifting Into Park . . . . . . . . . . . . . 279
Shifting out of Park . . . . . . . . . . . 280
Parking over Things That Burn . . . . . . . . . . . . . . . . . . . 281
Active Fuel Management . . . . . 281
Engine Exhaust
Engine Exhaust . . . . . . . . . . . . . . 282
Running the Vehicle While Parked . . . . . . . . . . . . . . . . . . . . . . 282
Automatic Transmission
Automatic Transmission . . . . . . 283
Manual Mode . . . . . . . . . . . . . . . . . 286
Tow/Haul Mode . . . . . . . . . . . . . . . 288
Drive Systems
Four-Wheel Drive . . . . . . . . . . . . . 289
Brakes
Antilock BrakeSystem (ABS) . . . . . . . . . . . . . . . 297
Parking Brake . . . . . . . . . . . . . . . . 297
Brake Assist . . . . . . . . . . . . . . . . . . 298
Hill Start Assist (HSA) . . . . . . . . 298
Ride Control Systems
Traction Control/Electronic Stability Control . . . . . . . . . . . . . 299 Hill Descent Control (HDC) . . . 301
Locking Rear Axle . . . . . . . . . . . . 302
Cruise Control
Cruise Control . . . . . . . . . . . . . . . . 302
Driver Assistance Systems
Driver Assistance Systems . . . 305
Assistance Systems for
Parking or Backing . . . . . . . . . . 306
Assistance Systems for Driving . . . . . . . . . . . . . . . . . . . . . . 308
Forward Collision Alert (FCA) System . . . . . . . . . . . . . . . . . . . . . . 308
Forward Automatic Braking (FAB) . . . . . . . . . . . . . . . 310
Lane Departure Warning (LDW) (2500/3500
Series) . . . . . . . . . . . . . . . . . . . . . . 312
Lane Keep Assist (LKA) (1500 Series) . . . . . . . . . . . . . . . . . . . . . . 313
Fuel
Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 315
California FuelRequirements . . . . . . . . . . . . . . . 316
Fuels in Foreign Countries . . . 316
Fuel Additives . . . . . . . . . . . . . . . . 316
E85 or FlexFuel . . . . . . . . . . . . . . 317
Filling the Tank . . . . . . . . . . . . . . . 317
Filling a Portable Fuel Container . . . . . . . . . . . . . . . . . . . 319

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
278 Driving and Operating
Engine Coolant Heater
The engine heater can provide
easier starting and better fuel
economy during engine warm-up in
cold weather conditions at or below
−18 °C (0 °F). Vehicles with an
engine heater should be plugged in
at least four hours before starting.
An internal thermostat in the
plug-end of the cord may exist,
which will prevent engine coolant
heater operation at temperatures
above−18 °C (0 °F).
If the vehicle has a diesel engine,
see the Duramax diesel
supplement.
{Warning
Do not plug in the engine block
heater while the vehicle is parked
in a garage or under a carport.
Property damage or personal
injury may result. Always park the
vehicle in a clear open area away
from buildings or structures.
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The cord is
secured to the driver side
fender with a clip, next to the
engine compartment fuse
block. Carefully remove the
wire tie that bundles the
electrical plug. Do not cut the
electrical cord.
Check the heater cord for
damage. If it is damaged, do
not use it. See your dealer for
a replacement. Inspect the
cord for damage yearly.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{Warning
Improper use of the heater cord
or an extension cord can damage
the cord and may result in
overheating and fire.
. Plug the cord into a
three-prong electrical utility
receptacle that is protected
by a ground fault detection
function. An ungrounded
outlet could cause an
electric shock.
. Use a weatherproof,
heavy-duty, 15 amp-rated
extension cord if needed.
Failure to use the
recommended extension
cord in good operating
condition, or using a
damaged heater or
extension cord, could make
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Driving and Operating 279
Warning (Continued)
it overheat and cause a fire,
property damage, electric
shock, and injury.
. Do not operate the vehicle
with the heater cord
permanently attached to the
vehicle. Possible heater
cord and thermostat
damage could occur.
. While in use, do not let the
heater cord touch vehicle
parts or sharp edges. Never
close the hood on the
heater cord.
. Before starting the vehicle,
unplug the cord, reattach
the cover to the plug, and
securely fasten the cord.
Keep the cord away from
any moving parts. 4. Before starting the engine, be
sure to unplug and store the
cord as it was before to keep it
away from moving engine
parts. If you do not, it could be
damaged.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.
Shifting Into Park
{Warning
It can be dangerous to get out of
the vehicle if the shift lever is not
fully in P (Park) with the parking
brake firmly set. The vehicle can
roll. If you have left the engine
running, the vehicle can move
suddenly. You or others could be
injured. To be sure the vehicle will
not move, even when you are on
fairly level ground, use the steps
that follow. With four-wheel drive,
if the transfer case is in (Continued)
Warning (Continued)
N (Neutral), the vehicle will be
free to 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 0320.
1. Hold the brake pedal down, then set the parking brake.
See Parking Brake 0297.
2. Move the shift lever into the P (Park) position 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 ignition key to LOCK/OFF.
5. Remove the key and take it with you. If you can leave the
vehicle with the ignition key in
your hand, the vehicle is in
P (Park).

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Vehicle Care 373
5.3L V8 Engine Shown, 4.3L
V6 Engine and 6.2L V8 Engine Similar
1. Coolant Surge Tank
2. Coolant Surge TankPressure Cap
3. Engine Electric Cooling Fans (Out of View)
{Warning
An electric engine cooling fan can
start even when the engine is not
running. To avoid injury, always
(Continued)
Warning (Continued)
keep hands, clothing, and tools
away from any engine
cooling fan.
6.0L V8 Engine
1. Coolant Surge Tank
2. Coolant Surge TankPressure Cap
3. Engine Belt-Driven Cooling Fan (Out of View)
{Warning
Heater and radiator hoses, and
other engine parts, can be very
hot. Do not touch them. If you do,
you can be burned.
Do not run the engine if there is a
leak. If you run the engine, it
could lose all coolant. That could
cause an engine fire, and you
could be burned. Get any leak
fixed before you drive the vehicle.
Caution
Using coolant other than
DEX-COOL®can cause
premature engine, heater core,
or radiator corrosion. In addition,
the engine coolant could require
changing sooner. Any repairs
would not be covered by the
vehicle warranty. Always use
DEX-COOL (silicate-free) coolant
in the vehicle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Vehicle Care 377
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program
0478.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
4.3L V6, 5.3L V8, and 6.2L
V8 Engines
Check to see if the engine cooling
fans are running. If the engine is
overheating, the fans should be
running. If they are not, do not
continue to run the engine and have
the vehicle serviced.
If Steam is Coming from the
Engine Compartment
{Warning
Steam from an overheated engine
can burn you badly, even if you
just open the hood. Stay away
from the engine if you see or hear
steam coming from it. Just turn it (Continued)
Warning (Continued)
off and get everyone away from
the vehicle until it cools down.
Wait until there is no sign of
steam or coolant before you open
the hood.
If you keep driving when the
engine is overheated, the liquids
in it can catch fire. You or others
could be badly burned. Stop the
engine if it overheats, and get out
of the vehicle until the engine
is cool.
If No Steam is Coming from
the Engine Compartment
The ENGINE OVERHEATED STOP
ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message, along with a low coolant
condition, can indicate a serious
problem. If there is an engine overheat
warning, but no steam is seen or
heard, the problem may not be too
serious. Sometimes the engine can
get a little too hot when the vehicle:
.
Climbs a long hill on a hot day.
. Stops after high-speed driving.
. Idles for long periods in traffic.
. Tows a trailer; see Trailer Towing
0 323.
If the ENGINE OVERHEATED
STOP ENGINE or the ENGINE
OVERHEATED IDLE ENGINE
message appears with no sign of
steam, try this for a minute or so: 1. Turn the air conditioning off.
2. Turn the heater on to the highest temperature and to the
highest fan speed. Open the
windows as necessary.
3. When it is safe to do so, pull off the road, shift to P (Park) or
N (Neutral) and let the
engine idle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Vehicle Care 395
FusesUsage
19 Integrated chassis control module
20 Electronic suspension control
module
21 Fuel pump power module
22 Upfitter 1
23 Upfitter 2
24 Front wiper
25 ABS Valves
26 Upfitter 2
27 Upfitter 3
28 Right parking lamps
29 Left parking lamps
30 Upfitter 3
31 Upfitter 4
32 Upfitter 4
33 Reverse lamps
34 Engine control module/Ignition Fuses
Usage
35 A/C clutch
36 Heated mirrors
37 Upfitter 1
38 Center high-mounted
stoplamp
39 Miscellaneous/ Ignition
40 Transmission/ Ignition
41 Fuel pump 2
42 Cooling fan clutch
43 Engine
44 Fuel injectors A –odd
45 Fuel injectors B –even
46 O2 Sensor B
47 Throttle control
48 Horn
49 Fog lamps
50 O2 Sensor A Fuses
Usage
51 Engine control module
52 Interior heater
53 Accessory power module/TPM pump
54 Front washer
55 A/C/Battery regulated voltage
control
56 A/C module/ Battery pack
57 Transmission control module/
Engine control
module
58 Headlamps
74 Electric running boards (if
equipped)
76 Fuel pump prime
Relays Usage
59 Fuel pump
60 Upfitter 2

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-9955992) - 2017 - crc - 4/18/17
Index 501
Customer SatisfactionProcedure . . . . . . . . . . . . . . . . . . . . . 474
D
Damage Repair, Collision . . . . . . . 481
Danger, Warning, and Caution . . . . 3
Data Collection
Infotainment System . . . . . . . . . . 487
OnStar . . . . . . . . . . . . . . . . . . . . . . . 486
Data Recorders, Event . . . . . . . . . 486
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . 181
Defensive Driving . . . . . . . . . . . . . . . 254
Delayed Locking . . . . . . . . . . . . . . . . . 40
Diagnostics OnStar
®. . . . . . . . . . . . . . . . . . . . . . 492
Distracted Driving . . . . . . . . . . . . . . . 253
Dome Lamps . . . . . . . . . . . . . . . . . . . 185
Door
Ajar Light . . . . . . . . . . . . . . . . . . . . . 152
Ajar Messages . . . . . . . . . . . . . . . 158
Delayed Locking . . . . . . . . . . . . . . . . 40
Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . 39
Power Locks . . . . . . . . . . . . . . . . . . . . 40
Drive Belt Routing, Engine . . . . . . 473
Driver Assistance Systems . . . . . 305
Driver Information Center (DIC) . . . . . . . . . . . . . 152, 154 Driving
Assistance Systems . . . . . . . . . . 308
Characteristics and
Towing Tips . . . . . . . . . . . . . . . . . 320
Defensive . . . . . . . . . . . . . . . . . . . . . 254
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . 254
For Better Fuel Economy . . . . . . . 31
Hill and Mountain Roads . . . . . . 262
If the Vehicle is Stuck . . . . . . . . . 264
Loss of Control . . . . . . . . . . . . . . . 256
Off-Road . . . . . . . . . . . . . . . . . . . . . 257
Off-Road Recovery . . . . . . . . . . . 256
Vehicle Load Limits . . . . . . . . . . . 265
Wet Roads . . . . . . . . . . . . . . . . . . . 261
Winter . . . . . . . . . . . . . . . . . . . . . . . . 263
Dual Automatic Climate
Control System . . . . . . . . . . . . . . . . 246
E
E85 or FlexFuel . . . . . . . . . . . . . . . . 317
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . . 350
Electrical System Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 393
Fuses . . . . . . . . . . . . . . . . . . . . . . . . 393
Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . 396, 398
Overload . . . . . . . . . . . . . . . . . . . . . 392 Emergency
OnStar
®. . . . . . . . . . . . . . . . . . . . . . 489
Engine Air Cleaner/Filter . . . . . . . . . . . . . 371
Check Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . 144
Compartment Overview . . . . . . . 359
Coolant . . . . . . . . . . . . . . . . . . . . . . . 374
Coolant Heater . . . . . . . . . . . . . . . 278
Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 138
Coolant Temperature Warning Light . . . . . . . . . . . . . . . 149
Cooling System . . . . . . . . . . . . . . . 372
Cooling System Messages . . . 159
Drive Belt Routing . . . . . . . . . . . . 473
Exhaust . . . . . . . . . . . . . . . . . . . . . . 282
Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . 378
Oil Life System . . . . . . . . . . . . . . . 367
Oil Messages . . . . . . . . . . . . . . . . . 159
Oil Pressure Gauge . . . . . . . . . . 137
Oil Pressure Light . . . . . . . . . . . . 150
Overheated Protection Operating Mode . . . . . . . . . . . . . 378
Overheating . . . . . . . . . . . . . . . . . . 376
Power Messages . . . . . . . . . . . . . 160
Running While Parked . . . . . . . . 282
Starting . . . . . . . . . . . . . . . . . . . . . . . 275