2019 GMC SIERRA coolant temperature

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/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
334 Vehicle Care
.Helps keep the proper engine
temperature.
Caution
Do not use anything other than a
mix of DEX-COOL coolant that
meets GM Standard
GMW3420 and clean, drinkable
water. Anything else can cause
damage to the engine cooling
system and the vehicle, which
would not be covered by the
vehicle warranty.
Never dispose of engine coolant by
putting it in the trash, or by pouring
it on the ground, or into sewers,
streams, or bodies of water. Have
the coolant changed by an
authorized service center, familiar
with legal requirements regarding
used coolant disposal. This will help
protect the environment and your
health.
Checking Coolant
The coolant surge tank is in the
engine compartment on the driver
side of the vehicle. See Engine
Compartment Overview 0321.
The vehicle must be on a level
surface when checking the coolant
level.
Check to see if coolant is visible in
the coolant surge tank. If the coolant
inside the coolant surge tank is
boiling, wait until it cools down. The
coolant level should be at or above the indicated mark. If it is not, there
may be a leak in the cooling
system.
If coolant is visible but the coolant
level is not at or above the indicated
mark, see the following sections on
how to add coolant to the coolant
surge tank.
Automatic Coolant Service Fill
Instructions (L3B Engine)
See 3.0L Duramax Diesel
supplement for the diesel engine
procedure.
If equipped, this feature assists in
filling and removing air from the
cooling system after service of
components or when coolant is
added after being too low.
To activate the fill and air removal
process:
1. With a cold system, add coolant to the indicated mark
on the surge tank.
2. Replace the cap on the surge tank.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
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
338 Vehicle Care
3. When it is safe to do so, pull offthe road, shift to P (Park) or
N (Neutral) and let the
engine idle.
If the temperature overheat gauge is
no longer in the overheat zone or an
overheat warning no longer
displays, the vehicle can be driven.
Continue to drive the vehicle slowly
for about 10 minutes. Keep a safe
vehicle distance from the vehicle in
front. If the warning does not come
back on, continue to drive normally
and have the cooling system
checked for proper fill and function.
If the warning continues, pull over,
stop, and park the vehicle
right away.
If there is still no sign of steam and
the vehicle is equipped with an
engine driven cooling fan, push
down the accelerator until the
engine speed is about twice as fast
as normal idle speed for at least
five minutes while the vehicle is
parked. If the warning is still there,
turn off the engine and get everyone
out of the vehicle until it cools down. If there is no sign of steam, idle the
engine for five minutes while
parked. If the warning is still
displayed, turn off the engine until it
cools down.
Overheated Engine
Protection
Operating Mode
If an overheated engine condition
exists and the ENGINE POWER IS
REDUCED message displays, an
overheat protection mode which
alternates firing groups of cylinders
helps to prevent engine damage. In
this mode, a loss in power and
engine performance will be noticed.
This operating mode allows the
vehicle to be driven to a safe place
in an emergency. Driving extended
distances and/or towing a trailer in
the overheat protection mode
should be avoided.
Caution
After driving in the overheated
engine protection operating
mode, the engine oil will be
severely degraded. Any repairs
performed before the engine is
cool may cause engine damage.
Allow the engine to cool before
attempting any repair. Repair the
cause of coolant loss, change the
oil, and reset the oil life system.
See
Engine Oil 0326.
Engine Fan
The vehicle has electric cooling
fan(s). The fans may be heard
spinning at low speed during most
everyday driving. The fans may turn
off if no cooling is required. Under
heavy vehicle loading, trailer towing,
high outside temperatures,
or operation of the air conditioning
system, the fans may change to
high speed and an increase in fan
noise may be heard. This is normal
and indicates that the cooling
system is functioning properly. The

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-1500-11698638) - 2019 - CRC - 5/14/19
Vehicle Care 339
fans will change to low speed when
additional cooling is no longer
required.
The electric engine cooling fans
may run after the engine has been
turned off. This is normal and no
service is required.
Washer Fluid
What to Use
When windshield washer fluid needs
to be added, be sure to read the
manufacturer's instructions before
use. Use a fluid that has sufficient
protection against freezing in an
area where the temperature may fall
below freezing.
Adding Washer Fluid
The vehicle has a low washer fluid
message on the DIC that comes on
when the washer fluid is low. The
message is displayed for
15 seconds at the start of each
ignition cycle. When the WASHER
FLUID LOW ADD FLUID messagedisplays, washer fluid will need to
be added to the windshield washer
fluid reservoir.
Open the cap with the washer
symbol on it. Add washer fluid until
the tank is full. See
Engine
Compartment Overview 0321 for
reservoir location.
Caution
. Do not use washer fluid that
contains any type of water
repellent coating. This can
cause the wiper blades to
chatter or skip.
(Continued)
Caution (Continued)
.Do not use engine coolant
(antifreeze) in the
windshield washer. It can
damage the windshield
washer system and paint.
. Do not mix water with
ready-to-use washer fluid.
Water can cause the
solution to freeze and
damage the washer fluid
tank and other parts of the
washer system.
. When using concentrated
washer fluid, follow the
manufacturer instructions for
adding water.
. Fill the washer fluid tank
only three-quarters full when
it is very cold. This allows
for fluid expansion if
freezing occurs, which could
damage the tank if it is
completely full.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-1500-11698638) - 2019 - CRC - 5/13/19
466 Index
ChargingWireless . . . . . . . . . . . . . . . . . . . . . . 137
Charging System Light . . . . . . . . . 151
Check Engine Light (MalfunctionIndicator) . . . . . . . . . . . . . . . . . . . . 151
Ignition Transmission Lock . . . 348
Child Restraints Infants and Young Children . . . 101
Lower Anchors and Tethersfor Children . . . . . . . . . . . . . . . . . 107
Older Children . . . . . . . . . . . . . . . . 100
Securing . . . . . . . . . . . . . . . . . 118, 122
Systems . . . . . . . . . . . . . . . . . . . . . . 104
Circuit Breakers . . . . . . . . . . . . . . . . 355
Cleaning Exterior Care . . . . . . . . . . . . . . . . . 408
Interior Care . . . . . . . . . . . . . . . . . . 413
Climate Control Systems . . . . . . . 191 Air Conditioning . . . . . . . . . . . . . . 191
Dual Automatic . . . . . . . . . . . . . . . 193
Heating . . . . . . . . . . . . . . . . . . . . . . . 191
Clock . . . . . . . . . . . . . . . . . . . . . . . . . . . 134
Cluster, Instrument . . . . . . . . . . . . . 140
Collision Damage Repair . . . . . . . 445
Compartments Storage . . . . . . . . . . . . . . . . . . . . . . . 126
Compass . . . . . . . . . . . . . . . . . . . . . . . 134 Connected Services
Connections . . . . . . . . . . . . . . . . . . 461
Diagnostics . . . . . . . . . . . . . . . . . . . 463
Navigation . . . . . . . . . . . . . . . . . . . . 460
Connections Connected Services . . . . . . . . . . 461
Control
Hill Descent . . . . . . . . . . . . . . . . . . 249
Traction and ElectronicStability . . . . . . . . . . . . . . . . . . . . . 247
Control Light
Hill Descent . . . . . . . . . . . . . . . . . . 156
Control of a Vehicle . . . . . . . . . . . . . 201
Convex Mirrors . . . . . . . . . . . . . . . . . . 57
Coolant Engine Temperature Gauge . . 147
Engine Temperature
Warning Light . . . . . . . . . . . . . . . 158
Cooling . . . . . . . . . . . . . . . . . . . . 191, 193
Cooling System . . . . . . . . . . . . . . . . . 332
Courtesy Transportation Program . . . . . . . . . . . . . . . . . . . . . . . 444
Cruise Control . . . . . . . . . . . . . . . . . . 255 Light . . . . . . . . . . . . . . . . . . . . . . . . . . 161
Cupholders . . . . . . . . . . . . . . . . . . . . . 126
Customer Assistance . . . . . . . . . . . 441
Offices . . . . . . . . . . . . . . . . . . . . . . . . 440 Customer Assistance (cont'd)
Text Telephone (TTY)
Users . . . . . . . . . . . . . . . . . . . . . . . 441
Customer Information
Publications OrderingInformation . . . . . . . . . . . . . . . . . . 447
Customer Satisfaction Procedure . . . . . . . . . . . . . . . . . . . . . 438
D
Damage Repair, Collision . . . . . . . 445
Danger, Warning, and Caution . . . . 3
Data CollectionInfotainment System . . . . . . . . . . 451
OnStar . . . . . . . . . . . . . . . . . . . . . . . 451
Data Recorders, Event . . . . . . . . . 450
Daytime Running Lamps (DRL) . . . . . . . . . . . . . . . . . . 182
Defensive Driving . . . . . . . . . . . . . . . 201
Delayed Locking . . . . . . . . . . . . . . . . . 46
Diagnostics
Connected Services . . . . . . . . . . 463
Differential, Limited-Slip . . . . . . . . 255
Distracted Driving . . . . . . . . . . . . . . . 200
Dome Lamps . . . . . . . . . . . . . . . . . . . 186
Door Ajar Light . . . . . . . . . . . . . . . . . . . . . 161
Delayed Locking . . . . . . . . . . . . . . . . 46

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/-
Mexico-1500-11698638) - 2019 - CRC - 5/13/19
Index 467
Door (cont'd)Locks . . . . . . . . . . . . . . . . . . . . . . . . . . . 45
Power Locks . . . . . . . . . . . . . . . . . . . . 46
Drive Belt Routing, Engine . . . . . . 437
Driver Assistance Systems . . . . . 258
Driver Information
Center (DIC) . . . . . . . . . . . . . 161, 163
Driver Mode Control . . . . . . . . . . . . 250
Driver Mode Control Light . . . . . . 158
Driving Assistance Systems . . . . . . . . . . 265
Characteristics andTowing Tips . . . . . . . . . . . . . . . . . 281
Defensive . . . . . . . . . . . . . . . . . . . . . 201
Drunk . . . . . . . . . . . . . . . . . . . . . . . . . 201
For Better Fuel Economy . . . . . . . 30
Hill and Mountain Roads . . . . . . 209
If the Vehicle is Stuck . . . . . . . . . .211
Loss of Control . . . . . . . . . . . . . . . 203
Off-Road . . . . . . . . . . . . . . . . . . . . . 203
Off-Road Recovery . . . . . . . . . . . 202
Vehicle Load Limits . . . . . . . . . . . 212
Wet Roads . . . . . . . . . . . . . . . . . . . 208
Winter . . . . . . . . . . . . . . . . . . . . . . . . 210
Dual Automatic Climate Control System . . . . . . . . . . . . . . . . 193E
E85 or FlexFuel . . . . . . . . . . . . . . . . 278
Electric Parking Brake . . . . . . . . . . 245
Electric Parking Brake Light . . . . 154
Electrical Equipment,Add-On . . . . . . . . . . . . . . . . . . . . . . . 311
Electrical System Engine Compartment FuseBlock . . . . . . . . . . . . . . . . . . . . . . . . 355
Fuses and Circuit Breakers . . . 355
Instrument Panel Fuse
Block . . . . . . . . . . . . . . . . . . . 359, 361
Overload . . . . . . . . . . . . . . . . . . . . . 354
Electronic Stability Control
(ESC) Off Light . . . . . . . . . . . . . . . . 157
Emergency OnStar . . . . . . . . . . . . . . . . . . . . . . . 453
Engine Air Cleaner/Filter . . . . . . . . . . . . . 331
Check Light (Malfunction
Indicator) . . . . . . . . . . . . . . . . . . . . 151
Compartment Overview . . . . . . . 321
Coolant Temperature Gauge . . . . . . . . . . . . . . . . . . . . . . 147
Coolant Temperature Warning Light . . . . . . . . . . . . . . . 158
Cooling System . . . . . . . . . . . . . . . 332
Drive Belt Routing . . . . . . . . . . . . 437 Engine (cont'd)
Exhaust . . . . . . . . . . . . . . . . . . . . . . 232
Fan . . . . . . . . . . . . . . . . . . . . . . . . . . . 338
Heater . . . . . . . . . . . . . . . . . . . . . . . . 227
Oil Life System . . . . . . . . . . . . . . . 328
Oil Pressure Gauge . . . . . . . . . . 146
Oil Pressure Light . . . . . . . . . . . . 159
Overheated Protection
Operating Mode . . . . . . . . . . . . . 338
Overheating . . . . . . . . . . . . . . . . . . 336
Power Messages . . . . . . . . . . . . . 169
Running While Parked . . . . . . . . 232
Starting . . . . . . . . . . . . . . . . . . . . . . . 224
Engine Air Filter Life System . . . . 330
Entry Lighting . . . . . . . . . . . . . . . . . . . 187
Equipment, Towing . . . . . . . . . . . . . 290
Event Data Recorders . . . . . . . . . . 450
Exit Lighting . . . . . . . . . . . . . . . . . . . . 187
Extended Parking . . . . . . . . . . . . . . . 231
Extender, Seat Belt . . . . . . . . . . . . . . 85
Exterior Cargo Lamps . . . . . . . . . . 185
Exterior Lamp Controls . . . . . . . . . 179
Exterior Lamps Off Reminder . . . 181
Exterior Lighting Battery
Saver . . . . . . . . . . . . . . . . . . . . . . . . . 188