engine overheat GMC SIERRA DENALI 2019 User Guide

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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Vehicle Care 325
Automatic Transmission
Fluid When to Check and Change
Automatic Transmission Fluid It is usually not necessary to check
the transmission fluid level. The only
reason for fluid loss is a
transmission leak or overheated
transmission. This vehicle is not
equipped with a transmission fluid
level dipstick. There is a special
procedure for checking and
changing the transmission fluid in
these vehicles. Because this
procedure is difficult, this should be
done at the dealer. Contact the
dealer for additional information or
the procedure can be found in the
service manual. See Publication
Ordering Information 0 442 .
Caution
Use of the incorrect automatic
transmission fluid may damage
the vehicle, and the damage may
(Continued) Caution (Continued) not be covered by the vehicle
warranty. Always use the correct
automatic transmission fluid. See
Recommended Fluids and
Lubricants 0 425 .
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule
0 415 . Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0 425 .
Engine Air Filter Life
System When to Change the Engine
Air Filter
When the “ Replace at Next Oil
Change ” message displays, the
engine air filter should be replaced
at the time of the next engine oil
change. When the “ Replace Engine
Air Filter Now ” message displays,
the engine air filter should be replaced as soon as possible. Reset
the engine air filter life system after
the engine air filter is replaced. See
your dealer for service and to reset
the system.
If equipped, this feature provides an
indication of when to change the
engine air filter. It is based on
driving conditions, which can cause
when to change to vary greatly. It is
possible an air filter change may not
be indicated for up to four years.
How to Reset the Engine Air
Filter Life System To reset:
1. Place the vehicle in P (Park).
2. Display the Air Filter Life on the
DIC.
See Driver Information Center
(DIC) (Midlevel and Uplevel)
0 160 or Driver Information
Center (DIC) (Base Level)
0 159 .
3. Press
T to move to the Reset/
Disable display area. Select
Reset then press
V .

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
328 Vehicle Care
5.3L V8 Engine (L84) Shown, 5.3L
V8 Engine (L82) and 6.2L
V8 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. { WarningDo 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 0 331 . What to Use
{ WarningPlain 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/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
330 Vehicle Care 3. Connect the vehicle to a
battery charger.
4. Turn the ignition on for Key
Access vehicles or to Service
Only for Keyless Access
vehicles.
See Ignition Positions (Key
Access) 0 217 or Ignition
Positions (Keyless Access)
0 219 .
5. Turn off the air conditioning.
6. Set the parking brake.
7. At the same time, press the
accelerator and the brake for
automatic transmission
vehicles for two seconds, then
release.
At the end of the cycle, check the
coolant level in the surge tank and
add coolant if it is low. Turn off the
vehicle, allow the Electronic Control
Module (ECM) to go to sleep, about
2 minutes, and repeat Steps 3-7.
Listen for pump activation and
movement of the control valves
while watching the level of the
coolant in the surge tank. If the tank empties, turn the ignition off,
carefully remove the surge tank cap,
refill to the COLD FILL mark, and
repeat Steps 3-6. The fill and air
removal process will run for
approximately 10 minutes.
How to Add Coolant to the
Coolant Surge Tank for
Gasoline Engines Except L3B If the vehicle has a diesel engine,
see “ Cooling System ” in the
Duramax diesel supplement for the
proper coolant fill procedure.
{ WarningSpilling coolant on hot engine
parts can burn you. Coolant
contains ethylene glycol and it will
burn if the engine parts are hot
enough. { WarningPlain 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.
{ WarningSteam 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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - crc - 5/15/18
Vehicle Care 331CautionFailure 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.
CautionIf 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.