
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
222 Driving and Operating CautionCranking 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 pushing the
accelerator pedal all the way to
the floor and holding it there
while holding the key in START
or ENGINE START/STOP for
up to a maximum of
15 seconds. Wait at least
15 seconds between each try,
to allow the cranking motor to
cool down. When the engine
starts, let go of the key or button and accelerator. If the
vehicle starts briefly but then
stops again, do the same thing.
This clears the extra gasoline
from the engine. Do not race
the engine immediately after
starting it. Operate the engine
and transmission gently until
the oil warms up and lubricates
all moving parts.
Stop/Start System If equipped, the Stop/Start system
will shut off the engine to help
conserve fuel. It has components
designed for the increased number
of starts.
{ Warning
The automatic engine Stop/Start
feature causes the engine to shut
off while the vehicle is still on. Do
not exit the vehicle before shifting
to P (Park). The vehicle may
restart and move unexpectedly.
(Continued) Warning (Continued) Always shift to P (Park), and then
turn the ignition off before exiting
the vehicle.
Auto Engine Stop/Start
When the brakes are applied and
the vehicle is at a complete stop,
the engine may turn off. When
stopped, the tachometer displays
AUTO STOP. See Tachometer
0 143 . When the brake pedal is
released or the accelerator pedal is
pressed, the engine will restart.
To maintain vehicle performance,
other conditions may cause the
engine to automatically restart
before the brake pedal is released.
Auto Stops may not occur and/or
Auto Starts may occur because:
.
The climate control settings
require the engine to be running
to cool or heat the vehicle
interior.
.
The vehicle battery charge
is low.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
224 Driving and Operating
Base model shown other models
are similar
3. Remove the engine heater
connector cover by gently
prying with a flat blade tool. 4. Plug the heater cord into the
connector in the front fascia.
5. Plug the cord into a grounded
110-volt AC outlet that is
protected by a ground fault
detection function. { WarningImproper 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-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 225Warning (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.
6. Before starting the engine, be
sure to unplug and store
the cord. 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.
Retained Accessory
Power (RAP) Some vehicle accessories may be
used after the ignition is turned off.
The power windows and sunroof,
if equipped, will continue to work for
up to 10 minutes or until any door is
opened.
The infotainment system will
continue to work for 10 minutes,
until the driver door is opened,
or until the ignition is turned on or
placed in ACC/ACCESSORY. Shifting Into Park
{ WarningIt 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
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, see Driving Characteristics
and Towing Tips 0 276 .
1. Hold the brake pedal down,
then set the parking brake. See
Electric Parking Brake 0 241 .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
226 Driving and Operating 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 off. For Key
Access, push the ignition key
in, towards the steering column
and then turn the ignition off.
5. For Key Access, 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).
For Keyless Access, take the
Remote Keyless Entry (RKE)
transmitter with you. Leaving the Vehicle with the
Engine Running
{ WarningIt 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.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 279The 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 Overheating 0 331 .
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 0 253 . Parking on Hills
{ WarningTo 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/
Mexico-1500-11698638) - 2019 - crc - 5/16/18
Driving and Operating 281the drive mode that is
appropriate for the road
conditions.
CautionIf 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 0 415 . It is
especially important to check the
automatic transmission fluid, 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
0 331 .
Trailer Towing If equipped with a diesel engine,
see the Duramax diesel
supplement.
CautionTowing 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
{ WarningNever 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 - 5/16/18
Driving and Operating 307
Adding a Snow Plow or
Similar Equipment CautionDo not exceed 72 km/h (45 mph)
with a snow plow mounted to the
vehicle. The vehicle could
overheat and be damaged.
Before installing a snow plow on the
vehicle, follow these guidelines:
CautionIf the vehicle does not have the
snow plow prep package, RPO
VYU, adding a plow can damage
the vehicle, and the repairs would
not be covered by the vehicle
warranty. Unless the vehicle was
built to carry a snow plow, do not
add one to the vehicle. If the
vehicle has RPO VYU, then the
payload the vehicle can carry will
be reduced when a snow plow is
(Continued) Caution (Continued) installed. The vehicle can be
damaged if either the front or rear
axle ratings or the Gross Vehicle
Weight Rating (GVWR) are
exceeded.
The plow the vehicle can carry
depends on many things, such as:
.
The options the vehicle came
with, and the weight of those
options.
.
The weight and number of
passengers to be carried.
.
The weight of items added to the
vehicle, like a tool box or
truck cap.
.
The total weight of any
additional cargo to be carried.
For example, if the snow plow
weighs 318 kg (700 lb), the total
weight of all occupants and cargo
inside the cab should not exceed
135 kg (300 lb). This means that you
may only be able to carry one
passenger. Even this may be too much if there is other equipment
already adding to the weight of the
vehicle.
To safely carry a snow plow on the
vehicle:
.
Follow all aftermarket snow plow
manufacturer ’ s instructions for
the operation and transportation
of the snow plow.
.
With a snow plow attached, the
engine coolant temperature
gauge may show a higher
temperature than while driving
without one. The snow plow
could block the airflow to the
radiator. This could be more
noticeable as vehicle speed
increases. At speeds above
72 km (45 mph), this may cause
the engine coolant to overheat.
.
To increase the airflow, move the
snow plow blade postion.
.
If driving more than 24 km
(15 mi), angle the plow blade
position.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Vehicle Care 311
Vehicle Care General Information General Information . . . . . . . . . . 312
California Proposition
65 Warning . . . . . . . . . . . . . . . . . 313
California Perchlorate
Materials Requirements . . . . . 313
Accessories and
Modifications . . . . . . . . . . . . . . . . 313
Vehicle Checks Doing Your Own
Service Work . . . . . . . . . . . . . . . 314
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 314
Engine Compartment
Overview . . . . . . . . . . . . . . . . . . . . 316
Engine Oil . . . . . . . . . . . . . . . . . . . . 321
Engine Oil Life System . . . . . . . 323
Automatic Transmission
Fluid . . . . . . . . . . . . . . . . . . . . . . . . 325
Engine Air Filter Life
System . . . . . . . . . . . . . . . . . . . . . . 325
Engine Air Cleaner/Filter . . . . . . 326
Cooling System . . . . . . . . . . . . . . 327
Engine Overheating . . . . . . . . . . 331
Overheated Engine Protection
Operating Mode . . . . . . . . . . . . . 333
Engine Fan . . . . . . . . . . . . . . . . . . . 333 Washer Fluid . . . . . . . . . . . . . . . . . 334
Brakes . . . . . . . . . . . . . . . . . . . . . . . 335
Brake Pad Life System . . . . . . . 335
Brake Fluid . . . . . . . . . . . . . . . . . . . 336
Battery - North America . . . . . . 337
Four-Wheel Drive . . . . . . . . . . . . . 340
Front Axle . . . . . . . . . . . . . . . . . . . . 340
Rear Axle . . . . . . . . . . . . . . . . . . . . 341
Noise Control System . . . . . . . . 342
Starter Switch Check . . . . . . . . . 343
Ignition Transmission Lock
Check . . . . . . . . . . . . . . . . . . . . . . . 343
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . 343
Wiper Blade Replacement . . . . 344
Windshield Replacement . . . . . 345
Gas Strut(s) . . . . . . . . . . . . . . . . . . 345
Headlamp Aiming Headlamp Aiming . . . . . . . . . . . . 346
Bulb Replacement Bulb Replacement . . . . . . . . . . . . 346
Halogen Bulbs . . . . . . . . . . . . . . . . 346
LED Lighting . . . . . . . . . . . . . . . . . 347
Headlamps, Front Turn Signal,
Sidemarker, and Parking
Lamps . . . . . . . . . . . . . . . . . . . . . . 347
Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 347 Center High-Mounted
Stoplamp (CHMSL) and
Cargo Lamp . . . . . . . . . . . . . . . . . 348
License Plate Lamp . . . . . . . . . . 349
Electrical System Electrical System Overload . . . 349
Fuses and Circuit Breakers . . . 350
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . 350
Instrument Panel Fuse Block
(Right) . . . . . . . . . . . . . . . . . . . . . . 354
Instrument Panel Fuse
Block (Left) . . . . . . . . . . . . . . . . . 356
Wheels and Tires Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 358
All-Season Tires . . . . . . . . . . . . . . 359
Winter Tires . . . . . . . . . . . . . . . . . . 359
Low-Profile Tires . . . . . . . . . . . . . 360
All-Terrain Tires . . . . . . . . . . . . . . . 360
Tire Sidewall Labeling . . . . . . . . 360
Tire Designations . . . . . . . . . . . . . 363
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 364
Tire Pressure . . . . . . . . . . . . . . . . . 367
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . . 368
Tire Pressure Monitor
System . . . . . . . . . . . . . . . . . . . . . . 369