change time GMC SIERRA DENALI 2020 Service Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
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) 0147 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0148.
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) 0147 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0148.
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 - 8/27/19
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 0458.
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)
0 147 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0148.
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 - 8/27/19
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 Pressure
0387 and
Vehicle Load Limits 0200.
Check that all wheel nuts are
properly tightened. See “Wheel
Nut Torque” underCapacities
and Specifications 0458, 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.
(Continued)
Warning (Continued)
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.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Service and Maintenance 441
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. 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)
0147 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0148 for
hourmeter, if equipped.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Service and Maintenance 445
Maintenance Schedule
Additional Required
Services - Normal12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi 180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Replace brake fluid. (7)
Replace windshield wiper blades. (8)
@ @ @ @ @ @ @ @ @ @
Replace hood gas struts and tailgate
dampener. (9)@ @
Replace air conditioning desiccant. (10)
Footnotes—Maintenance
Schedule Additional Required
Services - Normal
(1) Or every two years, whichever
comes first. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy
traffic, poor air quality, areas with
high dust levels or are sensitive to
environmental allergens. Filter
replacement may also be needed if
you notice reduced airflow, windows
fogging up, or odors. Your local GM Service location can help you
determine when it is the right time to
replace your filter.
(2)
Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0344.
(3) Visually check all fuel and vapor
lines and hoses for proper
attachment, connection, routing, and
condition. (4)
Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water
can overcome the seals and
contaminate the fluid. Contaminated
fluid will decrease the life of the
transfer case and/or drive axles and
should be replaced.
(5) Or every five years, whichever
comes first. See Cooling System
0 346.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
448 Service and Maintenance
Footnotes—Maintenance
Schedule Additional Required
Services - Severe
(1) Or every two years, whichever
comes first. More frequent
replacement may be needed if the
vehicle is driven in areas with heavy
traffic, poor air quality, areas with
high dust levels or are sensitive to
environmental allergens. Filter
replacement may also be needed if
you notice reduced airflow, windows
fogging up, or odors. Your local GM
Service location can help you
determine when it is the right time to
replace your filter.
(2) Or every four years, whichever
comes first. If driving in dusty
conditions, inspect the filter at each
oil change or more often as needed.
See Engine Air Cleaner/Filter 0344.
(3) Visually check all fuel and vapor
lines and hoses for proper
attachment, connection, routing, and
condition. (4)
Do not directly power wash the
transfer case and/or front/rear axle
output seals. High pressure water
can overcome the seals and
contaminate the fluid. Contaminated
fluid will decrease the life of the
transfer case and/or drive axles and
should be replaced.
(5) Or every five years, whichever
comes first. See Cooling System
0 346.
(6) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage;
replace, if needed.
(7) Replace brake fluid every five
years. See Brake Fluid 0357.
(8) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0364.
(9) Or every 10 years, whichever
comes first. See Gas Strut(s)0365.
(10) Replace air conditioning
desiccant every seven years.Special Application
Services
. Vehicles with Dual Wheels:
Check dual wheel nut torque at
160, 1 600, and 10 000 km (100,
1,000, and 6,000 mi) of driving.
Repeat this service whenever a
tire/wheel is serviced or
removed.
. Severe Commercial Use
Vehicles Only: Lubricate chassis
components every oil change.
. Have underbody flushing service
performed. See “Underbody
Maintenance” inExterior Care
0 429.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
466 Customer Information
Center at 1-800-323-9935. Text
Telephone (TTY) users, call
1-800-833-9935.
General Motors of Canada also has
a Mobility program. See www.gm.ca
or call 1-800-GM-DRIVE
(800-463-7483) for details. TTY
users call 1-800-263-3830.
Roadside Assistance
Program
For U.S.-purchased vehicles, call
1-888-881-3302; (Text Telephone
(TTY): 1-888-889-2438).
For Canadian-purchased vehicles,
call 1-800-268-6800.
Service is available 24 hours a day,
365 days a year.
Calling for Assistance
When calling Roadside Assistance,
have the following information
ready:
.Your name, home address, and
home telephone number
. Telephone number of your
location .
Location of the vehicle
. Model, year, color, and license
plate number of the vehicle
. Odometer reading, Vehicle
Identification Number (VIN), and
delivery date of the vehicle
. Description of the problem
Coverage
Services are provided for the
duration of the vehicle's powertrain
warranty.
In the U.S., anyone driving the
vehicle is covered. In Canada, a
person driving the vehicle without
permission from the owner is not
covered.
Roadside Assistance is not a part of
the New Vehicle Limited Warranty.
General Motors North America and
GMC reserve the right to make any
changes or discontinue the
Roadside Assistance program at
any time without notification.
General Motors North America and
GMC reserve the right to limit
services or payment to an owner or driver if they decide the claims are
made too often, or the same type of
claim is made many times.
Services Provided
.
Emergency Fuel Delivery:
Delivery of enough fuel for the
vehicle to get to the nearest
service station.
. Lock-Out Service: Service to
unlock the vehicle if you are
locked out. A remote unlock may
be available if you have OnStar.
For security reasons, the driver
must present identification
before this service is given.
. Emergency Tow from a Public
Road or Highway: Tow to the
nearest GMC dealer for warranty
service, or if the vehicle was in a
crash and cannot be driven.
Assistance is not given when the
vehicle is stuck in the sand,
mud, or snow.
. Flat Tire Change: Service to
change a flat tire with the spare
tire. The spare tire, if equipped,
must be in good condition and
properly inflated. It is the owner's

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Customer Information 469
Additional Program
Information
All program options, such as shuttle
service, may not be available at
every dealer. Contact your dealer
for specific availability.
General Motors reserves the right to
unilaterally modify, change,
or discontinue Courtesy
Transportation at any time and to
resolve all questions of claim
eligibility pursuant to the terms and
conditions described herein at its
sole discretion.
Collision Damage Repair
If the vehicle is involved in a
collision and it is damaged, have the
damage repaired by a qualified
technician using the proper
equipment and quality replacement
parts. Poorly performed collision
repairs diminish the vehicle resale
value, and safety performance can
be compromised in subsequent
collisions.
Collision Parts
Genuine GM Collision parts are new
parts made with the same materials
and construction methods as the
parts with which the vehicle was
originally built. Genuine GM
Collision parts are the best choice to
ensure that the vehicle's designed
appearance, durability, and safety
are preserved. The use of Genuine
GM parts can help maintain the GM
New Vehicle Limited Warranty.
Recycled original equipment parts
may also be used for repair. These
parts are typically removed from
vehicles that were total losses in
prior crashes. In most cases, the
parts being recycled are from
undamaged sections of the vehicle.
A recycled original equipment GM
part may be an acceptable choice to
maintain the vehicle's originally
designed appearance and safety
performance; however, the history of
these parts is not known. Such parts
are not covered by the GM New
Vehicle Limited Warranty, and any
related failures are not covered by
that warranty.Aftermarket collision parts are also
available. These are made by
companies other than GM and may
not have been tested for the vehicle.
As a result, these parts may fit
poorly, exhibit premature durability/
corrosion problems, and may not
perform properly in subsequent
collisions. Aftermarket parts are not
covered by the GM New Vehicle
Limited Warranty, and any vehicle
failure related to such parts is not
covered by that warranty.
Repair Facility
GM also recommends that you
choose a collision repair facility that
meets your needs before you ever
need collision repairs. Your dealer
may have a collision repair center
with GM-trained technicians and
state-of-the-art equipment, or be
able to recommend a collision repair
center that has GM-trained
technicians and comparable
equipment.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
478 OnStar
Security
If equipped, OnStar provides these
services:
.With Stolen Vehicle Assistance,
OnStar Advisors can use GPS to
pinpoint the vehicle and help
authorities quickly recover it.
. With Remote Ignition Block,
if equipped, OnStar can block
the engine from being restarted.
. With Stolen Vehicle Slowdown,
if equipped, OnStar can work
with law enforcement to
gradually slow the vehicle down.
Theft Alarm Notification
If equipped, if the doors are locked
and the vehicle alarm sounds, a
notification by text, e-mail, or phone
call will be sent. If the vehicle is
stolen, an OnStar Advisor can work
with authorities to recover the
vehicle.
OnStar Additional
Information
In-Vehicle Audio Messages
Audio messages may play important
information at the following times:
.Prior to vehicle purchase.
Press
Qto set up an account.
. After change in ownership and
at 90 days.
Transferring Service
PressQto request account transfer
eligibility information. The Advisor
can cancel or change account
information.
Selling/Transferring the
Vehicle
Call 1-888-4ONSTAR
(1-888-466-7827) immediately to
terminate your OnStar or connected
services if the vehicle is disposed
of, sold, transferred, or if the
lease ends.
Reactivation for Subsequent
Owners
PressQand follow the prompts to
speak to an Advisor as soon as
possible. The Advisor will update
vehicle records and explain OnStar
or connected service options.
How OnStar Service Works
Automatic Crash Response,
Emergency Services, Crisis Assist,
Stolen Vehicle Assistance, Remote
Services, and Roadside Assistance
are available on most vehicles. Not
all OnStar services are available
everywhere or on all vehicles. For
more information, a full description
of OnStar services, system
limitations, and OnStar User Terms,
Privacy Statement, and Software
Terms:
. Call 1-888-4ONSTAR
(1-888-466-7827).
. See www.onstar.com (U.S.).
. See www.onstar.ca (Canada).
. Call TTY 1-877-248-2080.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
OnStar 479
.PressQto speak with an
Advisor.
OnStar or connected services
cannot work unless the vehicle is in
a place where OnStar has an
agreement with a wireless service
provider for service in that area. The
wireless service provider must also
have coverage, network capacity,
reception, and technology
compatible with OnStar or
connected services. Service
involving location information about
the vehicle cannot work unless GPS
signals are available, unobstructed,
and compatible with the OnStar
hardware. OnStar or connected
services may not work if the OnStar
equipment is not properly installed
or it has not been properly
maintained. If equipment or software
is added, connected, or modified,
OnStar or connected services may
not work. Other problems beyond
the control of OnStar —such as
hills, tall buildings, tunnels, weather,
electrical system design and
architecture of the vehicle, damage to the vehicle in a crash, or wireless
phone network congestion or
jamming
—may prevent service.
See Radio Frequency Statement
0 472.
Services for People with
Disabilities
Advisors provide services to help
with physical disabilities and
medical conditions.
Press
Qto help:
. Locate a gas station with an
attendant to pump gas.
. Find a hotel, restaurant, etc.,
that meets accessibility needs.
. Provide directions to the closest
hospital or pharmacy in urgent
situations.
TTY Users
OnStar has the ability to
communicate to deaf,
hard-of-hearing, or speech-impaired
customers while in the vehicle. The
available dealer-installed TTY
system can provide in-vehicle access to all OnStar services,
except Virtual Advisor and OnStar
Turn-by-Turn Navigation.
If equipped, TTY mode can be
turned on or off by touching
Settings, then Apps, and then
Phone. When TTY mode is on,
phone calls can be made or
received with OnStar using the
infotainment display.
OnStar Personal Identification
Number (PIN)
A PIN is needed to access some
OnStar services. The PIN will need
to be changed the first time when
speaking with an Advisor. To
change the OnStar PIN, contact an
OnStar Advisor by pressing
Qor
calling 1-888-4ONSTAR.
Warranty
OnStar equipment may be
warranted as part of the vehicle
warranty.