reset GMC SIERRA 2020 Owner's Guide

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 345
3. Disconnect the electricalharness connector (2) from the
cover.
4. Remove the three screws on top of the cover of the housing,
then slide and lift the cover.
5. Lift and remove the engine air cleaner/filter.
6. Lightly tap and shake the engine air cleaner/filter, away
from the vehicle, to release
loose dust and dirt. Replace
the engine air filter if damaged.
7. Reverse steps 2–5 to reinstall the engine air cleaner/filter
cover housing.
8. If equipped, reset the engine air filter life system after
replacing the engine air filter.
See Engine Air Filter Life
System 0343.
6.6L V8 Engine (L8T)
1. Locate the air cleaner/filter assembly. See Engine
Compartment Overview 0332.
2. Remove the eight screws on top of the cover of the housing,
then lift the cover.
3. Remove the engine air cleaner/ filter from the housing. Take
care to dislodge as little dirt as
possible.
4. Clean the engine air cleaner/ filter sealing surfaces and the
housing. 5. Inspect or replace the engine
air cleaner/filter.
6. Reverse Steps 2–4 to reinstall the filter cover housing.
7. If equipped, reset the engine air filter life system after
replacing the engine air filter.
see Engine Air Filter Life
System 0343.
{Warning
Operating the engine with the air
cleaner/filter off can cause you or
others to be burned. Use caution
when working on the engine. Do
not start the engine or drive the
vehicle with the air cleaner/filter
off, as flames may be present if
the engine backfires.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 353
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.
SeeEngine Oil 0339.
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
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

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
366 Vehicle Care
Caution
Do not apply tape or hang any
objects from gas struts. Also do
not push down or pull on gas
struts. This may cause damage to
the vehicle.
See Maintenance Schedule 0442.
Hood
Trunk
Liftgate
Headlamp Aiming
Headlamp aim has been preset and
should need no further adjustment.
If the vehicle is damaged in a crash,
the headlamp aim may be affected.
If adjustment to the headlamps is
necessary, see your dealer.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 393
.The battery of the TPMS sensor
is low.
If the tire fill alert does not operate
due to TPMS interference, move the
vehicle about 1 m (3 ft) back or
forward and try again. If the tire fill
alert feature is not working, use a
tire pressure gauge.
TPMS Sensor Matching
Process
Each TPMS sensor has a unique
identification code. The identification
code needs to be matched to a new
tire/wheel position after rotating the
vehicle’s tires or replacing one or
more of the TPMS sensors. Also,
the TPMS sensor matching process
should be performed after replacing
a spare tire with a road tire
containing the TPMS sensor. The
malfunction light and the DIC
message should go off at the next
ignition cycle. The sensors are
matched to the tire/wheel positions,
using a TPMS relearn tool, in the
following order: driver side front tire,
passenger side front tire, passenger
side rear tire, and driver side rear. See your dealer for service or to
purchase a relearn tool. A TPMS
relearn tool can also be purchased.
See Tire Pressure Monitor Sensor
Activation Tool at
www.gmtoolsandequipment.com or
call 1-800-GM TOOLS
(1-800-468-6657).
There are two minutes to match the
first tire/wheel position, and
five minutes overall to match all four
tire/wheel positions. If it takes
longer, the matching process stops
and must be restarted.
The TPMS sensor matching
process is:
1. Set the parking brake.
2. Turn the ignition on without starting the vehicle.
3. Uplevel DIC Only: Make sure the Tire Pressure info page
option is turned on. The info
pages on the DIC can be
turned on and off through the Options menu. See
Driver
Information Center (DIC) (Base
Level) 0148 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0149.
4. If the vehicle has an uplevel DIC, use the DIC controls on
the right side of the steering
wheel to scroll to the Tire
Pressure screen under the DIC
info page.
If the vehicle has a base level
DIC, use the trip odometer
reset stem to scroll to the Tire
Pressure screen.
5. If the vehicle has an uplevel DIC, press and hold the
thumbwheel located in the
center of the DIC controls on
the right side of the steering
wheel.
If the vehicle has a base level
DIC, press and hold the trip
odometer reset stem for about
five seconds. A message
asking if the process should
begin should appear. Select

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
394 Vehicle Care
yes and press the trip
odometer reset stem to confirm
the selection.
The horn sounds twice to
signal the receiver is in relearn
mode and the TIRE
LEARNING ACTIVE message
displays on the DIC screen.
6. Start with the driver side front tire.
7. Place the relearn tool against the tire sidewall, near the valve
stem. Then press the button to
activate the TPMS sensor.
A horn chirp confirms that the
sensor identification code has
been matched to this tire and
wheel position.
8. Proceed to the passenger side front tire, and repeat the
procedure in Step 7.
9. Proceed to the passenger side rear tire, and repeat the
procedure in Step 7.
10. Proceed to the driver side rear tire, and repeat the procedure
in Step 7. The horn sounds two times to indicate the sensor
identification code has been
matched to the driver side rear
tire, and the TPMS sensor
matching process is no longer
active. The TIRE LEARNING
ACTIVE message on the DIC
display screen goes off.
11. Turn the vehicle off.
12. Set all four tires to the recommended air pressure
level as indicated on the Tire
and Loading Information label.
Trailer Tire Pressure
Monitoring Operation
If equipped, the Trailer Tire
Pressure Monitoring System
(TTPMS) is designed to monitor the
pressure of the trailer tires and warn
the driver when a low pressure
condition exists. TTPMS sensors for
four tires are provided. The system
can accommodate a trailer with up
to six tires if additional sensors are
purchased from the dealer. Also, the
system can be paired with up to five
individual trailers. Prior to use, the vehicle must learn
the sensors by following the
learning process. See
Trailering App
0 310.Contact your trailer service center or
tire service center to have the
pressure sensors installed inside
the trailer tires. The technician
should insert the sensor stem
through the hole in the trailer wheel.
When the sensor is correctly
positioned, the nut on the sensor
stem should be tightened to 8 Y
(6 lb ft). When mounting the trailer
tire onto the trailer wheel be careful
not to damage the sensor.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
398 Vehicle Care
Use this rotation pattern when
rotating the tires if the vehicle
has polished forged aluminum
dual rear wheels. The spare
wheel can be used in any
position in the event of a flat tire,
and can be rotated with the rear
inner wheels. After the flat tire is
repaired, if the spare is not on
one of the inner rear positions, it
must be replaced by the correct
wheel in the front or rear outer
positions.
When installing dual wheels,
check that the vent holes in the
inner and outer wheels on each
side are lined up.
Adjust the front and rear tires to
the recommended inflation
pressure on the Tire and
Loading Information label after
the tires have been rotated. See
Tire Pressure0387 and
Vehicle Load Limits 0200. Check that all wheel nuts are
properly tightened. See
“Wheel
Nut Torque” underCapacities
and Specifications 0459, and
“Removing the Flat Tire and
Installing the Spare Tire” under
Tire Changing 0407.
{Warning
Rust or dirt on a wheel, or on the
parts to which it is fastened, can
make wheel nuts become loose
after time. The wheel could come
off and cause a crash. When
changing a wheel, remove any
rust or dirt from places where the
wheel attaches to the vehicle. In
an emergency, a cloth or a paper
towel can be used; however, use
a scraper or wire brush later to
remove all rust or dirt.
Lightly coat the inner diameter of
the wheel hub opening with
wheel bearing grease after a
wheel change or tire rotation to
prevent corrosion or rust build-up. Do not get grease on
the flat wheel mounting surface
or on the wheel nuts or bolts.
Reset the Tire Pressure Monitor
System (TPMS), if the vehicle
has one. See
Tire Pressure
Monitor Operation 0390.
If the full-size tire is part of the
tire rotation, make sure the tire
rotated into the spare position is
stored securely. Push, pull, and
then try to rotate or turn the tire.
If it moves, use the wheel
wrench/hoist shaft to tighten the
cable. See Tire Changing 0407.
When It Is Time for New
Tires
Factors, such as maintenance,
temperatures, driving speeds,
vehicle loading, and road conditions
affect the wear rate of the tires.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
428 Vehicle Care
light in the instrument cluster
will stop flashing and stay lit.
SeeFour-Wheel-Drive Light
0 142.
8. Start the engine. Check that the vehicle is in 2
m
(Two-Wheel Drive High) by
starting the engine and shifting
the transmission to D (Drive)
and then to R (Reverse). There
should be movement of the
vehicle while shifting.
9. Shift the transmission to P (Park) and turn off the
ignition.
10. Release the parking brake and remove the wheel blocks.
11. Reset any lost presets. The outside temperature
display will default to 0 °C (32 °
F) but will reset with normal
usage.
Dolly TowingCaution
Do not tow this vehicle with two
wheels on the ground, or vehicle
damage could occur. This
damage would not be covered by
the vehicle warranty.
Dolly towing this vehicle is not
allowed with either the front or the
rear tires on the ground for
two-wheel drive or four-wheel drive,
regardless of transfer case.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
442 Service and Maintenance
Refer to the information in the
Maintenance Schedule Additional
Required Services - Severe chart.
{Warning
Performing maintenance work can
be dangerous and can cause
serious injury. Perform
maintenance work only if the
required information, proper tools,
and equipment are available.
If they are not, see your dealer to
have a trained technician do the
work. SeeDoing Your Own
Service Work 0330.
Maintenance
Schedule
Owner Checks and Services
At Each Fuel Stop
.
Check the engine oil level. See
Engine Oil 0339.
Once a Month
. Check the tire inflation
pressures, including the spare.
See Tire Pressure 0387.
. Inspect the tires for wear. See
Tire Inspection 0396.
. Check the windshield washer
fluid level. See Washer Fluid
0 354.
Engine Oil Change
When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the
engine oil life system may not
indicate the need for vehicle service
for up to a year. The engine oil and filter must be changed at least once
a year and the oil life system must
be reset. Your trained dealer
technician can perform this work.
If the engine oil life system is reset
accidentally, service the vehicle
within 5 000 km/3,000 mi since the
last service. Reset the oil life
system when the oil is changed.
See
Engine Oil Life System 0341.
Engine Air Filter Change
When the REPLACE AT NEXT OIL
CHANGE message displays, the
engine air filter should be replaced
at the next engine oil change. When
the REPLACE ENGINE AIR FILTER
SOON message displays, the
engine air filter should be replaced
at the earliest convenience. Reset
the engine air filter life system after
the engine air filter is replaced. See
Engine Air Filter Life System 0343.
Passenger Compartment Air
Filter
The passenger compartment air
filter removes dust, pollen, and
other airborne irritants from outside
air that is pulled into the vehicle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/4/19
Service and Maintenance 443
The filter should be replaced as part
of routine scheduled maintenance.
Inspect the passenger compartment
air filter every 36 000 km/
22,500 miles or two years,
whichever comes first. Replace if
necessary. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy
traffic, areas with poor air quality,
or areas with high dust levels.
Replacement may also be needed if
there is a reduction in air flow,
excessive window fogging, or odors.
Power Take Off (PTO) and
Extended Idle Use
When the vehicle is used with the
PTO equipment or used in a way
that requires extended idle time,
one hour of use shall be deemed
the same as 53 km (33 mi). See
Driver Information Center (DIC)
(Base Level)0148 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0149 for
hourmeter, if equipped.
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. See Tire
Rotation 0396.
. Check engine oil level and oil
life percentage. If needed,
change engine oil and filter, and
reset oil life system. See Engine
Oil 0339 and
Engine Oil Life System 0341.
. 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 0343. If the
vehicle is not equipped with the
engine air filter life system,
inspect the engine air cleaner
filter. See Engine Air Cleaner/
Filter 0344.
. Check engine coolant level. See
Cooling System 0346.
. Check windshield washer fluid
level. See Washer Fluid 0354.
. Check tire inflation pressures,
including the spare. See Tire
Pressure 0387.
. Inspect tire wear. See Tire
Inspection 0396.
. Visually check for fluid leaks.
. Inspect brake system. See
Exterior Care 0429.
. 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
0 429. If equipped with grease