GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
340 Vehicle Care
If a low oil Driver Information Center
(DIC) message displays, check the
oil level.
Follow these guidelines:
.To get an accurate reading, park
the vehicle on level ground.
Check the engine oil level after
the engine has been off for at
least two hours. Checking the
engine oil level on steep grades
or too soon after engine shutoff
can result in incorrect readings.
Accuracy improves when
checking a cold engine prior to
starting. Remove the dipstick
and check the level.
. If unable to wait two hours, the
engine must be off for at least
15 minutes if the engine is
warm, or at least 30 minutes if
the engine is not warm. Pull out
the dipstick, wipe it with a clean
paper towel or cloth, then push it
back in all the way. Remove it
again, keeping the tip down, and
check the level.When to Add Engine Oil
If the oil is below the cross-hatched
area at the tip of the dipstick and
the engine has been off for at least
15 minutes, add 1 L (1 qt) of the
recommended oil and then recheck
the level. See “Selecting the Right
Engine Oil” later in this section for
an explanation of what kind of oil to
use. For engine oil crankcase
capacity, see Capacities and
Specifications 0459.
Caution
Do not add too much oil. Oil
levels above or below the
acceptable operating range
shown on the dipstick are harmful
to the engine. If the oil level is
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Caution (Continued)
above the operating range (i.e.,
the engine has so much oil that
the oil level gets above the
cross-hatched area that shows
the proper operating range), the
engine could be damaged. Drain
the excess oil or limit driving of
the vehicle, and seek a service
professional to remove the
excess oil.
See Engine Compartment Overview
0 332 for the location of the engine
oil fill cap.
Add enough oil to put the level
somewhere in the proper operating
range. Push the dipstick all the way
back in when through.
Selecting the Right Engine Oil
Selecting the right engine oil
depends on both the proper oil
specification and viscosity grade.
See Recommended Fluids and
Lubricants 0453.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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342 Vehicle Care
include engine revolutions, engine
temperature, and miles driven.
Based on driving conditions, the
mileage at which an oil change is
indicated can vary considerably. For
the oil life system to work properly,
the system must be reset every time
the oil is changed.
On some vehicles, when the system
has calculated that oil life has been
diminished, a CHANGE ENGINE
OIL SOON message comes on to
indicate that an oil change is
necessary. Change the oil as soon
as possible within the next 1 000 km
(600 mi). It is possible that, if driving
under the best conditions, the oil life
system might indicate that an oil
change is not necessary for up to a
year. The engine oil and filter must
be changed at least once a year
and, at this time, the system must
be reset. For vehicles without the
CHANGE ENGINE OIL SOON
message, an oil change is needed
when the REMAINING OIL LIFE
percentage is near 0%. Your dealer
has trained service people who will
perform this work and reset the
system. It is also important to checkthe oil regularly over the course of
an oil drain interval and keep it at
the proper level.
If the system is ever reset
accidentally, the oil must be
changed at 5 000 km (3,000 mi)
since the last oil change.
Remember to reset the oil life
system whenever the oil is changed.
How to Reset the Engine Oil
Life System
Reset the system whenever the
engine oil is changed so that the
system can calculate the next
engine oil change. Always reset the
engine oil life to 100% after every oil
change. It will not reset itself. To
reset the engine oil life system:
1. Display the oil life percentage on the DIC. See Driver
Information Center (DIC) (Base
Level) 0148 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0149.
2. Press the thumbwheel on the steering wheel, or the trip
odometer reset stem if the
vehicle does not have DIC controls, for several seconds.
When the confirmation
message displays, select YES.
The oil life will change
to 100%.
The oil life system can also be reset
as follows:
1. Display the oil life percentage on the DIC. See Driver
Information Center (DIC) (Base
Level) 0148 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0149.
2. Fully press the accelerator pedal slowly three times within
five seconds.
3. If the display changes to 100%, the system is reset.
If the vehicle has a CHANGE
ENGINE OIL SOON message and it
comes back on when the vehicle is
started and/or the oil life percentage
is near 0%, the engine oil life
system has not been reset. Repeat
the procedure.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 343
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. SeePublication
Ordering Information 0472.
Caution
Use of the incorrect automatic
transmission fluid may damage
the vehicle, and the damage may
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Caution (Continued)
not be covered by the vehicle
warranty. Always use the correct
automatic transmission fluid. See
Recommended Fluids and
Lubricants0453.
Change the fluid and filter at the
scheduled maintenance intervals
listed in Maintenance Schedule
0 442. Be sure to use the
transmission fluid listed in
Recommended Fluids and
Lubricants 0453.
Engine Air Filter Life
System
If equipped, this feature provides
the engine air filter ’s remaining life
and best timing for a change. The
timing to change an engine air filter
depends on driving and
environmental conditions.
When to Change the Engine
Air Filter
When the Driver Information Center
(DIC) displays a message to replace
the engine air filter at the next oil
change, follow this timing.
When the DIC displays a message
to replace the engine air filter soon,
replace the engine air filter at the
earliest convenience.
The system must be reset after the
engine air filter is changed.
If the DIC displays a message to
check the engine air filter system,
see your dealer.
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) (Base Level)
0 148 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0149.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
344 Vehicle Care
3. PressTon the steering wheel,
or press the trip odometer reset
stem if the vehicle does not
have DIC controls, to move to
the Reset/Disable display area.
Select Reset then press the
thumbwheel or press the reset
stem for several seconds.
4. Press the thumbwheel or the reset stem to confirm the reset.
Engine Air Cleaner/Filter
The engine air cleaner/filter is on
the driver side of the engine
compartment. See Engine
Compartment Overview 0332.
When to Inspect the Engine Air
Cleaner/Filter
If the vehicle is not equipped with
the engine air filter life system see
Maintenance Schedule 0442 for
intervals on inspecting and
replacing the engine air cleaner
filter.
How to Inspect/Replace the
Engine Air Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/
filter, make sure that the engine air
cleaner/filter housing and nearby
components are free of dirt and
debris. Do not clean the engine air
cleaner/filter or components with
water or compressed air.
To inspect or replace the engine air
cleaner/filter:
5.3L V8 Engine (L84) Shown, 2.7L
L4 Engine (L3B), 4.3L V6 Engine(LV3), 5.3L V8 Engine (L82), and
6.2L V8 Engine (L87) Similar
1. Air Duct Clamp
2. Electrical Harness Connector
3. Screws
1. Locate the air cleaner/filter assembly. See Engine
Compartment Overview 0332.
2. Disconnect the outlet duct by loosening the air duct
clamp (1).
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 351
6. Verify coolant level after theengine 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. 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 0134.
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
0 467.
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.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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352 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
0 292. 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
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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Vehicle Care 355
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 message
displays, 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. SeeEngine
Compartment Overview 0332 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.
. 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
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Caution (Continued)
for fluid expansion if
freezing occurs, which could
damage the tank if it is
completely full.
Brakes
Disc brake pads have built-in wear
indicators that make a high-pitched
warning sound when the brake pads
are worn and new pads are needed.
The sound can come and go or be
heard all the time the vehicle is
moving, except when applying the
brake pedal firmly.
{Warning
The brake wear warning sound
means that soon the brakes will
not work well. That could lead to
a crash. When the brake wear
warning sound is heard, have the
vehicle serviced.
GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
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356 Vehicle Care
Caution
Continuing to drive with worn-out
brake pads could result in costly
brake repair.
Some driving conditions or climates
can cause a brake squeal when the
brakes are first applied or lightly
applied. This does not mean
something is wrong with the brakes.
Properly torqued wheel nuts are
necessary to help prevent brake
pulsation. When tires are rotated,
inspect brake pads for wear and
evenly tighten wheel nuts in the
proper sequence to torque
specifications in Capacities and
Specifications 0459.
Brake linings should always be
replaced as complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal
does not return to normal height,
or if there is a rapid increase in
pedal travel. This could be a sign
that brake service may be required.
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed or parts are improperly
installed.
Brake Pad Life System
When to Change Brake Pads
This vehicle has a system that
estimates the remaining life of the
front and rear brake pads. Brake
pad life is displayed in the Driver
Information Center (DIC), along with
a percentage for each axle. The
system must be reset every time the
brake pads are changed.
When the system has determined
that the brake pads need to be
replaced, a message will display,
which may include mileage
remaining. Brake pads should always be
replaced as complete axle sets.
How to Reset the Brake Pad
Life System
The system will automatically detect
when significantly worn brake pads
are replaced. When the ignition is
turned on after new pads and wear
sensors are installed, a message
will display. Follow the prompts to
reset the system.
The brake pad life system can also
be manually reset:
1. Display Brake Pad Life on the DIC. See Driver Information
Center (DIC) (Base Level)
0 148 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0149.
2. Press the thumbwheel or the trip odometer reset stem if the
vehicle does not have DIC
buttons. Select front or rear
pads as appropriate.
3. Select YES on the confirmation message, or press the trip
odometer reset stem on a base