
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
284 Driving and Operating
The vehicle can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts too
often under heavy loads and/or hilly
conditions.
When towing at higher altitudes,
engine coolant will boil at a lower
temperature than at lower altitudes.
If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the
vehicle could show signs similar to
engine overheating. To avoid this,
let the engine run, preferably on
level ground, with the transmission
in P (Park) for a few minutes before
turning the engine off. If the
overheat warning comes on, see
Engine Overheating0336.
Viewing Systems
If equipped, the viewing systems on
the vehicle can improve visibility
while hitching, backing, and driving
with a trailer. See Driver Assistance
Systems 0258.
Parking on Hills
{Warning
To prevent serious injury or death,
always park your vehicle and
trailer on a level surface when
possible.
When parking your vehicle and your
trailer on a hill: 1. Press the brake pedal, but do not shift into P (Park) yet. Turn
the wheels into the curb if
facing downhill or into traffic if
facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, gradually release the
brake pedal to allow the chocks
to absorb the load of the trailer.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
.Start the engine.
. Shift into a gear.
. Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Launching and Retrieving
a Boat
Backing the Trailer into the Water
{Warning
.Have all passengers get out
of the vehicle before
backing onto the sloped part
of the ramp. Lower the
driver and passenger side
windows before backing
onto the ramp. This will
(Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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286 Driving and Operating
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 Schedule0420. 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
0 336.
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,
durability, and fuel economy. 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.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring
the weight, speed, altitude, road
grades, outside temperature, and
how frequently the vehicle is used to
tow a trailer.
Trailer Weight Ratings
When towing a trailer, the combined
weight of the vehicle, vehicle
contents, trailer, and trailer contents

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
316 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . . . . . 317
California Proposition65 Warning . . . . . . . . . . . . . . . . . 318
California Perchlorate Materials Requirements . . . . . 318
Accessories and Modifications . . . . . . . . . . . . . . . . 318
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 319
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 319
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 321
Engine Oil . . . . . . . . . . . . . . . . . . . . 326
Engine Oil Life System . . . . . . . 328
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 330
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 330
Engine Air Cleaner/Filter . . . . . . 331
Cooling System . . . . . . . . . . . . . . 332
Engine Overheating . . . . . . . . . . 336
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 338
Engine Fan . . . . . . . . . . . . . . . . . . . 338 Washer Fluid . . . . . . . . . . . . . . . . . 339
Brakes . . . . . . . . . . . . . . . . . . . . . . . 340
Brake Pad Life System . . . . . . . 340
Brake Fluid . . . . . . . . . . . . . . . . . . . 341
Battery - North America . . . . . . 342
Four-Wheel Drive . . . . . . . . . . . . . 345
Front Axle . . . . . . . . . . . . . . . . . . . . 345
Rear Axle . . . . . . . . . . . . . . . . . . . . 346
Noise Control System . . . . . . . . 347
Starter Switch Check . . . . . . . . . 348
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 348
Park Brake and P (Park) Mechanism Check . . . . . . . . . . 348
Wiper Blade Replacement . . . . 349
Windshield Replacement . . . . . 350
Gas Strut(s) . . . . . . . . . . . . . . . . . . 350
Headlamp Aiming
Front Headlamp Aiming . . . . . . 351
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 351
Halogen Bulbs . . . . . . . . . . . . . . . . 351
LED Lighting . . . . . . . . . . . . . . . . . 352
Headlamps, Front Turn Signal, Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 352
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 352 Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 353
License Plate Lamp . . . . . . . . . . 354
Electrical System
Electrical System Overload . . . 354
Fuses and Circuit Breakers . . . 355
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 355
Instrument Panel Fuse Block (Right) . . . . . . . . . . . . . . . . . . . . . . 359
Instrument Panel Fuse Block (Left) . . . . . . . . . . . . . . . . . 361
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 363
All-Season Tires . . . . . . . . . . . . . . 364
Winter Tires . . . . . . . . . . . . . . . . . . 364
Low-Profile Tires . . . . . . . . . . . . . 365
All-Terrain Tires . . . . . . . . . . . . . . . 365
Tire Sidewall Labeling . . . . . . . . 365
Tire Designations . . . . . . . . . . . . . 368
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 369
Tire Pressure . . . . . . . . . . . . . . . . . 372
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 373
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 374

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 333
5.3L V8 Engine (L84) Shown, 5.3LV8 Engine (L82) and 6.2LV8 Engine (L87) Similar
1. Engine Electric Cooling Fans (Out of View)
2. Coolant Surge Tank and Pressure Cap
{Warning
An underhood electric fan can
start up even when the engine is
not running and can cause injury.
Keep hands, clothing, and tools
away from any underhood
electric fan.
{Warning
Do not touch heater, radiator, a/c
pipes or hoses, or other engine
parts. They can be very hot and
can burn you. Do not run the
engine if there is a leak; all
coolant could leak out. That could
cause an engine fire and can
burn you. Fix any leak before
driving the vehicle.
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL engine
coolant. This coolant is designed to
remain in the vehicle for 5 years or
240 000 km (150,000 mi), whichever
occurs first.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating 0336.
What to Use
{Warning
Plain water, or other liquids such
as alcohol, can boil before the
proper coolant mixture will. With
plain water or the wrong mixture,
the engine could get too hot but
there would not be an overheat
warning. The engine could catch
fire and you or others could be
burned.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
coolant. This mixture:
. Gives freezing protection down
to−37 °C (−34 °F), outside
temperature.
. Gives boiling protection up to
129 °C (265 °F), engine
temperature.
. Protects against rust and
corrosion.
. Will not damage aluminum parts.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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336 Vehicle Care
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could
cause system damage. If coolant
is not visible in the surge tank,
contact your dealer.
If no coolant is visible in the surge
tank, add coolant.
1. Remove the coolant surge tank pressure cap when the cooling
system, including the coolant
surge tank pressure cap and
upper radiator hose, is no
longer hot. Turn the pressure cap slowly
counterclockwise about one full
turn. If a hiss is heard, wait for
that to stop. A hiss means
there is still some pressure left.
2. Keep turning the pressure cap slowly, and remove it.
3. Fill the coolant surge tank with the proper mixture to the full
cold mark.
4. With the coolant surge tank pressure cap off, start the
engine and let it run until the
engine coolant temperature
gauge indicates approximately
90 °C (195 °F).
By this time, the coolant level
inside the coolant surge tank
may be lower. If the level is
lower, add more of the proper
mixture to the coolant surge
tank until the level reaches the
indicated mark.
5. Replace the pressure cap tightly. 6. Verify coolant level after the
engine is shut off and the
coolant is cold. If necessary,
repeat coolant fill procedure
Steps 1–6.
Caution
If the pressure cap is not tightly
installed, coolant loss and engine
damage may occur. Be sure the
cap is properly and tightly
secured.
Engine Overheating
If the vehicle has the Duramax
diesel engine, see the Duramax
diesel supplement.
Caution
Do not run the engine if there is a
leak in the engine cooling system.
This can cause a loss of all
coolant and can damage the
system and vehicle. Have any
leaks fixed right away.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 337
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature
gauge in the vehicle's instrument
cluster. SeeEngine Coolant
Temperature Gauge 0147.
In addition, there are ENGINE
OVERHEATED STOP ENGINE,
ENGINE OVERHEATED IDLE
ENGINE, and ENGINE POWER IS
REDUCED messages in the Driver
Information Center (DIC).
If the decision is made not to lift the
hood when this warning appears,
get service help right away. See
Roadside Assistance Program
0 442.
If the decision is made to lift the
hood, make sure the vehicle is
parked on a level surface.
2.7L L4, 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. Have the
vehicle serviced.
If Steam is Coming from the
Engine Compartment
{Warning
Steam and scalding liquids from a
hot cooling system are under
pressure. Turning the pressure
cap, even a little, can cause them
to come out at high speed and
you could be burned. Never turn
the cap when the cooling system,
including the pressure cap, is hot.
Wait for the cooling system and
pressure cap to 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.The 2.7L engine will shut down
automatically if the ENGINE
OVERHEATED STOP ENGINE
message displays.
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
0 286.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
360 Vehicle Care
BackThe vehicle may not be equipped
with all of the fuses, relays, and
features shown.
Fuses Usage
F1 Right doors
F2 Left doors
F3 Universal remote system
F4 –
F5 –
F6 Front blower
F8 Lumbar switch
F10 Body control module 6/Body control
module 7
F11 Seat/CLM
F12 Body control module 3/Body control
module 5
F14 Mirrors/Windows module
F17 Steering wheel controls
F18 VPM/OBS DET Fuses Usage
F19 DLIS
F20 Cooled seats
F21 NOT R/C
F22 Heated steering wheel
F23 MISC R/C
F24 Instrument panel cluster ignition/
Overhead
F25 Heating, ventilation, and air conditioning
ignition/Heating,
ventilation, and air
conditioning auxiliary
F26 USB ports/Special equipment option
retained accessory
power
F27 Accessory power outlet/retained
accessory power
F28 Accessory power outlet/Battery

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 361
FusesUsage
F30 Sensing and diagnostic module/
Parking brake
F31 Body control module 4
F32 Special equipment option/Data link
connection
F33 Body control module 8
F34 Cargo lamp
F40 CGM
F41 Infotainment 1
F42 TCP
F43 –
F44 AVM
F45 Body control module 2
F46 Heating, ventilation, and air conditioning/
Battery 1
F47 Instrument panel cluster/Battery
F48 Transmission control module Fuses
Usage
F49 Body control module 1
F50 –
F51 Battery 1
F52 Battery 2
F53 –
F54 Sunroof
F55 Driver power seat
F56 DC DC TRANS 1
F57 DC DC TRANS 2
F58 Infotainment 2
Circuit
Breakers Usage
1 Accessory power outlet 2
2 Accessory power outlet 1/Cigarette
Lighter
3 Accessory power outlet 3
4 Accessory power outlet 4 Relays
Usage
K1 Run/Crank
K2 Retained accessory power/Accessory 1
K4 Retained accessory power/Accessory 2
K5 –
Instrument Panel Fuse
Block (Left)
The left instrument panel fuse block
access door is on the driver side
edge of the instrument panel.