2020 CHEVROLET SILVERADO cooling

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
346 Vehicle Care
Warning (Continued)
warning. The engine could catch
fire and you or others could be
burned.
{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.
Caution
Failure to follow the specific
coolant fill procedure could cause
the engine to overheat and could(Continued)
Caution (Continued)
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.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
Vehicle Care 347
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.
The vehicle has several indicators
to warn of engine overheating. There is a coolant temperature
gauge in the vehicle's instrument
cluster. See
Engine Coolant
Temperature Gauge 0131.
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
0 462.
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 and have
the vehicle serviced. If the engine or transmission detects
an impending hot fluid condition,
then the transmission may force
upshifts to limit temperatures.
Downshifts may also be prevented
in this instance. Normal operation
may continue unless the display
indicates there is a hot condition
and engine should be idled.
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.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
348 Vehicle Care
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 L4 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
0 288. 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.
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

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
Vehicle Care 349
in an emergency. Driving extended
distances and/or towing a trailer in
the overheat protection mode
should be avoided.
If the engine or transmission detects
an impending hot fluid condition,
then the transmission may force
upshifts to limit temperatures.
Downshifts may also be prevented
in this instance. Normal operation
may continue unless the display
indicates there is a hot condition
and engine should be idled.
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.
SeeEngine Oil 0335.
Engine Fan
If the vehicle has the Duramax
diesel engine, see the Duramax
diesel supplement.
All Engines Except 6.6L
V8 Engine (L8T)
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
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.
6.6L V8 Engine (L8T) Only
The vehicle has a clutched engine
cooling fan. When the clutch is
engaged, the fan spins faster to
provide more air to cool the engine.
In most everyday driving conditions,
the fan is spinning slower and the
clutch is not fully engaged. This
improves fuel economy and reduces
fan noise. Under heavy vehicle
loading, trailer towing, and/or high
outside temperatures, the fan speed
increases as the clutch more fully
engages, so an increase in fan
noise may be heard. This is normal
and should not be mistaken as the
transmission slipping or making
extra shifts. It is merely the cooling
system functioning properly. The fan
will slow down when additional
cooling is not required and the
clutch partially disengages.
This fan noise may be heard when
starting the engine. It will go away
as the fan clutch partially
disengages.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
Vehicle Care 369
FusesUsage
27 Horn
28 –
29 –
30 –
31 –
32 Rear window defogger
33 Heated mirror
34 Parking lamp left
37 Euro trailer
38 TIM
39 –
40 Misc ignition
41 Trailer parking lamp
42 Park lamp right
44 –
45 Second fuel pump
46 Engine control module ignition Fuses
Usage
47 Transmission control module
ignition
48 –
49 Transmission control module
50 A/C clutch
51 Transfer case control module
52 Front wiper
53 Center high-mounted
stop lamp
54 Trailer reverse lamp
55 Trailer back-up lamp
56 SADS
57 TTPM
58 Starter motor (LD & HD DSL)
60 Active fuel management 1 Fuses
Usage
61 VES
62 Integrated chassis control
module/CVS
63 Trailer battery
65 Auxiliary underhood
electrical center
66 Cooling fan motor left
67 Active fuel management 2
68 –
69 Starter Pinion (LD) / Starter Motor
(HD Gas)
71 Cooling fan
72 Cooling fan right
73 Trailer stop/turn lamp left
74 TIM
75 DEFC
76 Electric RNG BDS

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
370 Vehicle Care
FusesUsage
78 Engine control module
79 Auxiliary battery
80 Cabin cooling pump
81 Trailer stop/turn lamp right
82 TIM
83 FTZM
84 Trailer brake
85 ENG
86 Engine control module
87 Injector B even
88 O2 B sensor
89 O2 A sensor
90 Injector A odd
91 Engine control module throttle
control
92 Cool fan clutch Relays
Usage
5 Headlamp
18 DC/AC inverter
23 Rear window defogger
35 Parking lamp
36 Run/Crank
43 Second fuel pump
59 A/C clutch
64 Starter Motor (LD & HD DSL) / Cool
Fan Clutch
(HD Gas)
70 Starter Pinion (LD) / Starter Motor
(HD Gas)
77 PowertrainInstrument Panel Fuse
Block (Left)
The left instrument panel fuse block
access door is on the driver side
edge of the instrument panel.
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.
Pull off the cover to access the fuse
block. A fuse puller is available in
the left instrument panel end cap.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
Vehicle Care 399
performance which all
passenger car tires must meet
under the Federal Motor Safety
Standard No. 109. Grades B and
A represent higher levels of
performance on the laboratory
test wheel than the minimum
required by law. Warning: The
temperature grade for this tire is
established for a tire that is
properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned
and balanced at the factory to
provide the longest tire life and best
overall performance. Adjustments to
wheel alignment and tire balancing
are not necessary on a regular
basis. Consider an alignment check
if there is unusual tire wear or the
vehicle is significantly pulling to oneside or the other. Some slight pull to
the left or right, depending on the
crown of the road and/or other road
surface variations such as troughs
or ruts, is normal. If the vehicle is
vibrating when driving on a smooth
road, the tires and wheels may need
to be rebalanced. See your dealer
for proper diagnosis.
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or
corroded. If wheel nuts keep coming
loose, the wheel, wheel bolts and
wheel nuts should be replaced.
If the wheel leaks air, replace it.
Some aluminum wheels can be
repaired. See your dealer if any of
these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the
same load-carrying capacity,
diameter, width, offset and be
mounted the same way as the one it
replaces.
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor
System (TPMS) sensors with new
GM original equipment parts.
{Warning
Using the wrong replacement
wheels, wheel bolts, or wheel
nuts can be dangerous. It could
affect the braking and handling of
the vehicle. Tires can lose air,
and cause loss of control, causing
a crash. Always use the correct
wheel, wheel bolts, and wheel
nuts for replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or
odometer calibration, headlamp
aim, bumper height, vehicle
ground clearance, and tire or tire
chain clearance to the body and
chassis.

Chevrolet Silverado Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
13337620) - 2020 - CTC - 1/27/20
438 Service and Maintenance
Air Conditioning Desiccant
(Replace Every Seven Years)
The air conditioning system requires
maintenance every seven years.
This service requires replacement of
the desiccant to help the longevity
and efficient operation of the air
conditioning system. This service
can be complex. See your dealer.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi
Rotate the tires, if recommended for
the vehicle, and perform the
following services. SeeTire
Rotation 0392.
. Check engine oil level and oil
life percentage. If needed,
change engine oil and filter, and
reset oil life system. See Engine
Oil 0335 and
Engine Oil Life System 0337.
. If equipped with the engine air
filter life system, check the air
filter life percentage.
If necessary, replace the engine
air filter and reset the engine air filter life system. See
Engine Air
Filter Life System 0339. If the
vehicle is not equipped with the
engine air filter life system,
inspect the engine air cleaner
filter. See Engine Air Cleaner/
Filter 0340.
. Check engine coolant level. See
Cooling System 0342.
. Check windshield washer fluid
level. See Washer Fluid 0350.
. Check tire inflation pressures,
including the spare. See Tire
Pressure 0383.
. Inspect tire wear. See Tire
Inspection 0392.
. Visually check for fluid leaks.
. Inspect brake system. See
Exterior Care 0424.
. Visually inspect steering,
suspension, and chassis
components for damage,
including cracks or tears in the
rubber boots, loose or missing
parts, or signs of wear at least
once a year. See Exterior Care
0 424. If equipped with grease fittings, lubricate the suspension
and steering components every
other oil change for normal
usage and every oil change for
severe usage.
. Inspect power steering for
proper attachment, connections,
binding, leaks, cracks,
chafing, etc.
. Visually inspect drive shafts for
excessive wear, lubricant leaks
or damage including: tube dents,
cracks, constant velocity joint or
universal joint looseness,
cracked or missing boots, loose
or missing boot clamps, center
bearing excessive looseness,
missing or loose fasteners.
. Check restraint system
components. See Safety System
Check 068.
. Visually inspect fuel system for
damage or leaks.
. Visually inspect exhaust system
and nearby heat shields for
loose or damaged parts.
. Lubricate body components. See
Exterior Care 0424.