warning GMC SIERRA DENALI 2020 Owners Manual

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 379
Wheels and Tires
Tires
Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer. See
the warranty manual for
information regarding the tire
warranty and where to get
service. For additional
information refer to the tire
manufacturer.
{Warning
.Poorly maintained and
improperly used tires are
dangerous.
.Overloading the tires can
cause overheating as a
result of too much
flexing. There could be a
blowout and a serious
crash. SeeVehicle Load
Limits 0200.
(Continued)
Warning (Continued)
.Underinflated tires pose
the same danger as
overloaded tires. The
resulting crash could
cause serious injury.
Check all tires frequently
to maintain the
recommended pressure.
Tire pressure should be
checked when the tires
are cold.
.Overinflated tires are
more likely to be cut,
punctured, or broken by
a sudden impact —such
as when hitting a pothole.
Keep tires at the
recommended pressure.
.Worn or old tires can
cause a crash. If the
tread is badly worn,
replace them.
(Continued)
Warning (Continued)
.Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc.
.Improperly repaired tires
can cause a crash. Only
the dealer or an
authorized tire service
center should repair,
replace, dismount, and
mount the tires.
.Do not spin the tires in
excess of 56 km/h
(35 mph) on slippery
surfaces such as snow,
mud, ice, etc. Excessive
spinning may cause the
tires to explode.
All-Season Tires
This vehicle may come with
all-season tires. These tires are
designed to provide good overall

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
388 Vehicle Care
{Warning
Neither tire underinflation nor
overinflation is good.
Underinflated tires, or tires
that do not have enough air,
can result in:
.Tire overloading and
overheating which could
lead to a blowout.
.Premature or
irregular wear.
.Poor handling.
.Reduced fuel economy.
Overinflated tires, or tires that
have too much air, can
result in:
.Unusual wear.
.Poor handling.
.Rough ride.
.Needless damage from
road hazards. The Tire and Loading
Information label on the vehicle
indicates the original equipment
tires and the correct cold tire
inflation pressures. The
recommended pressure is the
minimum air pressure needed to
support the vehicle's maximum
load carrying capacity.
For additional information
regarding how much weight the
vehicle can carry, and an
example of the Tire and Loading
Information label, see
Vehicle
Load Limits 0200. How the
vehicle is loaded affects vehicle
handling and ride comfort. Never
load the vehicle with more
weight than it was designed to
carry.
When to Check
Check the pressure of the tires
once a month or more. Do not forget the spare tire,
if the vehicle has one. See
Full-Size Spare Tire
0418 for
additional information.
How to Check
Use a good quality pocket-type
gauge to check tire pressure.
Proper tire inflation cannot be
determined by looking at the tire.
Check the tire inflation pressure
when the tires are cold, meaning
the vehicle has not been driven
for at least three hours or no
more than 1.6 km (1 mi).
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to
get a pressure measurement.
If the cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the inflation pressure is low,
add air until the recommended
pressure is reached. If the

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 389
inflation pressure is high, press
on the metal stem in the center
of the tire valve to release air.
Re-check the tire pressure with
the tire gauge.
Put the valve caps back on the
valve stems to keep out dirt and
moisture and prevent leaks. Use
only valve caps designed for the
vehicle by GM. TPMS sensors
could be damaged and would
not be covered by the vehicle
warranty.
Tire Pressure for
High-Speed Operation
{Warning
Driving at high speeds, 160 km/h
(100 mph) or higher, puts
additional strain on tires.
Sustained high-speed driving
causes excessive heat buildup
and can cause sudden tire failure.(Continued)
Warning (Continued)
This could cause a crash, and
you or others could be killed.
Some high-speed rated tires
require inflation pressure
adjustment for high-speed
operation. When speed limits and
road conditions allow the vehicle
to be driven at high speeds, make
sure the tires are rated for
high-speed operation, are in
excellent condition, and are set to
the correct cold tire inflation
pressure for the vehicle load.
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor
the air pressure in your tires and
transmit tire pressure readings to a
receiver located in the vehicle. Each tire, including the spare (if
provided), should be checked
monthly when cold and inflated to
the inflation pressure recommended
by the vehicle manufacturer on the
vehicle placard or tire inflation
pressure label. (If your vehicle has
tires of a different size than the size
indicated on the vehicle placard or
tire inflation pressure label, you
should determine the proper tire
inflation pressure for those tires.)
As an added safety feature, your
vehicle has been equipped with a
tire pressure monitoring system
(TPMS) that illuminates a low tire
pressure telltale when one or more
of your tires is significantly
under-inflated.
Accordingly, when the low tire
pressure telltale illuminates, you
should stop and check your tires as
soon as possible, and inflate them
to the proper pressure. Driving on a
significantly under-inflated tire
causes the tire to overheat and can
lead to tire failure. Under-inflation
also reduces fuel efficiency and tire

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
390 Vehicle Care
tread life, and may affect the
vehicle's handling and stopping
ability.
Please note that the TPMS is not a
substitute for proper tire
maintenance, and it is the driver's
responsibility to maintain correct tire
pressure, even if under-inflation has
not reached the level to trigger
illumination of the TPMS low tire
pressure telltale.
Your vehicle has also been
equipped with a TPMS malfunction
indicator to indicate when the
system is not operating properly.
The TPMS malfunction indicator is
combined with the low tire pressure
telltale. When the system detects a
malfunction, the telltale will flash for
approximately one minute and then
remain continuously illuminated.
This sequence will continue upon
subsequent vehicle start-ups as
long as the malfunction exists.
When the malfunction indicator is
illuminated, the system may not be
able to detect or signal low tire
pressure as intended. TPMS
malfunctions may occur for a varietyof reasons, including the installation
of replacement or alternate tires or
wheels on the vehicle that prevent
the TPMS from functioning properly.
Always check the TPMS malfunction
telltale after replacing one or more
tires or wheels on your vehicle to
ensure that the replacement or
alternate tires and wheels allow the
TPMS to continue to function
properly.
See
Tire Pressure Monitor
Operation 0390.
See Radio Frequency Statement
0 472.
Tire Pressure Monitor
Operation
This vehicle may have a Tire
Pressure Monitor System (TPMS).
The TPMS is designed to warn the
driver when a low tire pressure
condition exists. TPMS sensors are
mounted onto each tire and wheel
assembly, excluding the spare tire
and wheel assembly. The TPMS
sensors monitor the air pressure in the tires and transmit the tire
pressure readings to a receiver
located in the vehicle.
When a low tire pressure condition
is detected, the TPMS illuminates
the low tire pressure warning light
located on the instrument cluster.
If the warning light comes on, stop
as soon as possible and inflate the
tires to the recommended pressure
shown on the Tire and Loading
Information label. See
Vehicle Load
Limits 0200.
A message to check the pressure in
a specific tire displays in the Driver
Information Center (DIC). The low
tire pressure warning light and the
DIC warning message come on at
each ignition cycle until the tires are
inflated to the correct inflation
pressure. If the vehicle has DIC
buttons, tire pressure levels can be

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 391
viewed. For additional information
and details about the DIC operation
and displays, seeDriver Information
Center (DIC) (Base Level) 0147 or
Driver Information Center (DIC)
(Midlevel and Uplevel) 0148.
The low tire pressure warning light
may come on in cool weather when
the vehicle is first started, and then
turn off as the vehicle is driven. This
could be an early indicator that the
air pressure is getting low and
needs to be inflated to the proper
pressure.
A Tire and Loading Information label
shows the size of the original
equipment tires and the correct
inflation pressure for the tires when
they are cold. See Vehicle Load
Limits 0200, for an example of the
Tire and Loading Information label
and its location. Also see Tire
Pressure 0387.
The TPMS can warn about a low
tire pressure condition but it does
not replace normal tire
maintenance. See Tire Inspection
0 396, Tire Rotation 0396 and
Tires 0379.Caution
Tire sealant materials are not all
the same. A non-approved tire
sealant could damage the TPMS
sensors. TPMS sensor damage
caused by using an incorrect tire
sealant is not covered by the
vehicle warranty. Always use only
the GM approved tire sealant
available through your dealer or
included in the vehicle.
TPMS Malfunction Light and
Message
The TPMS will not function properly
if one or more of the TPMS sensors
are missing or inoperable. When the
system detects a malfunction, the
low tire pressure warning light
flashes for about one minute and
then stays on for the remainder of
the ignition cycle. A DIC warning
message also displays. The
malfunction light and DIC warning
message come on at each ignition cycle until the problem is corrected.
Some of the conditions that can
cause these to come on are:
.
One of the road tires has been
replaced with the spare tire. The
spare tire does not have a
TPMS sensor. The malfunction
light and the DIC message
should go off after the road tire
is replaced and the sensor
matching process is performed
successfully. See "TPMS Sensor
Matching Process" later in this
section.
. The TPMS sensor matching
process was not done or not
completed successfully after
rotating the tires. The
malfunction light and the DIC
message should go off after
successfully completing the
sensor matching process. See
"TPMS Sensor Matching
Process" later in this section.
. One or more TPMS sensors are
missing or damaged. The
malfunction light and the DIC
message should go off when the
TPMS sensors are installed and

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
392 Vehicle Care
the sensor matching process is
performed successfully. See
your dealer for service.
. Replacement tires or wheels do
not match the original equipment
tires or wheels. Tires and wheels
other than those recommended
could prevent the TPMS from
functioning properly. See Buying
New Tires 0399.
. Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TPMS could cause the TPMS
sensors to malfunction.
If the TPMS is not functioning
properly, it cannot detect or signal a
low tire pressure condition. See
your dealer for service if the TPMS
malfunction light and DIC message
come on and stay on.
Tire Fill Alert (If Equipped)
This feature provides visual and
audible alerts outside the vehicle to
help when inflating an underinflated
tire to the recommended cold tire
pressure. When the low tire pressure warning
light comes on:
1. Park the vehicle in a safe, level place.
2. Set the parking brake firmly.
3. Place the vehicle in P (Park).
4. Add air to the tire that is underinflated. The turn signal
lamp will flash.
When the recommended
pressure is reached, the horn
sounds once and the turn
signal lamp will stop flashing
and briefly turn solid.
Repeat these steps for all
underinflated tires that have
illuminated the low tire pressure
warning light.
{Warning
Overinflating a tire could cause
the tire to rupture and you or
others could be injured. Do not
exceed the maximum pressure (Continued)
Warning (Continued)
listed on the tire sidewall. See
Tire Sidewall Labeling 0381 and
Vehicle Load Limits 0200.
If the tire is overinflated by more
than 35 kPa (5 psi), the horn will
sound multiple times and the turn
signal lamp will continue to flash for
several seconds after filling stops.
To release and correct the pressure,
while the turn signal lamp is still
flashing, briefly press the center of
the valve stem. When the
recommended pressure is reached,
the horn sounds once.
If the turn signal lamp does not flash
within 15 seconds after starting to
inflate the tire, the tire fill alert has
not been activated or is not working.
If the hazard warning flashers are
on, the tire fill alert visual feedback
will not work properly.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 395
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 8Y
(6 lb ft). When mounting the trailer
tire onto the trailer wheel be careful
not to damage the sensor.
The Trailering App can be used to
view the tire pressures after the
recommended trailer tire pressures
have been entered. Refer to the trailer tire placard on the trailer or
the trailer tire sidewall for the
recommended tire pressure.
The system is compatible with trailer
tires that have placard pressure
values from 103 - 689 kpa
(15 - 100 psi). The hole in the wheel
for the tire stem must be 11.43 mm
(0.453 in) in diameter. Use of the
pressure sensors on a wheel with a
different stem hole size could result
in loss of air from the tire.
If a low trailer tire pressure condition
is detected, the TTPMS displays a
warning message on the DIC. If the
warning message is displayed, stop
as soon as possible and inflate the
tires to the recommended pressure
shown on the tire placard on the
trailer.
In addition, the TTPMS monitors the
temperature of the trailer tires. If the
system detects a high temperature
on one or more of the trailer tires, a
warning message will be displayed
on the DIC. If this warning message
is displayed, stop as soon as
possible, and inspect the
overheated trailer tire. Commoncauses for high trailer tire
temperature are underinflation,
overloading, or tire damage.
TTPMS Malfunction Message
The TTPMS will not function
properly if one or more of the trailer
tire sensors are missing or
inoperable. If the system detects a
malfunction, a DIC message
indicates that the system requires
service. Some of the conditions that
can cause the service message to
occur are:
.
One of the trailer tires has been
replaced with the spare tire
which does not have a learned
TTPMS sensor. The DIC
message should turn off after the
pressure sensor is installed in
the tire, and the learning process
is performed successfully. See
"TTPMS Sensor Learning
Process" under Trailering App
0 310.
. The TTPMS sensor learning
process was not done or not
completed successfully. The DIC
message should go off after

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 8/27/19
Vehicle Care 397
Use this rotation pattern when
rotating the tires if the vehicle
has single rear wheels.
Dual Tire Rotation
When the vehicle is new,
or whenever a wheel, wheel
bolt, or wheel nut is replaced or
serviced, check the wheel nut
torque after 160, 1 600, and
10 000 km (100, 1,000, and
6,000 mi) of driving. For proper
torque and wheel nut tightening
information, see“Removing the
Flat Tire and Installing the Spare
Tire” under Tire Changing 0407 and
“Wheel Nut Torque” under
Capacities and Specifications
0 458 and “Removing the Flat
Tire and Installing the Spare
Tire” under Tire Changing 0407.
The outer tire on a dual wheel
setup generally wears faster
than the inner tire. Tires last
longer and wear more evenly if
they are rotated. See Tire
Inspection 0396 and
Tire Rotation 0396. Also see
Maintenance Schedule 0441.
{Warning
If the vehicle is operated with a
tire that is underinflated, the tire
can overheat. An overheated tire
can lose air suddenly or catch
fire. You or others could be
injured. Properly inflate all tires,
including the spare.
See Tire Pressure 0387, for
information on proper tire
inflation.
Use this rotation pattern when
rotating the tires if the vehicle
has dual rear wheels (except
polished forged aluminum
wheels).
Vehicles with polished forged
aluminum dual wheels have
three unique wheels; a front, a
rear outer and a rear inner.
These wheels cannot be rotated
to another position, however,
they can be rotated from left to
right to the same position.

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
400 Vehicle Care
Specification (TPC Spec)
system rating. When
replacement tires are needed,
GM strongly recommends
buying tires with the same TPC
Spec rating.
GM's exclusive TPC Spec
system considers over a dozen
critical specifications that impact
the overall performance of the
vehicle, including brake system
performance, ride and handling,
traction control, and tire
pressure monitoring
performance. GM's TPC Spec
number is molded onto the tire's
sidewall near the tire size. If the
tires have an all-season tread
design, the TPC Spec number
will be followed by MS for mud
and snow. SeeTire Sidewall
Labeling 0381 for additional
information.
GM recommends replacing worn
tires in complete sets of four (six
for dual rear wheels). Uniform tread depth on all tires will help
to maintain the performance of
the vehicle. Braking and
handling performance may be
adversely affected if all the tires
are not replaced at the same
time. If proper rotation and
maintenance have been done,
all four tires (six for dual rear
wheels) should wear out at
about the same time. See
Tire
Rotation 0396 for information
on proper tire rotation. However,
if it is necessary to replace only
one axle set of worn tires, place
the new tires on the rear axle
(two for single rear wheels, four
for dual rear wheels).
{Warning
Tires could explode during
improper service. Attempting
to mount or dismount a tire
could cause injury or death.
(Continued)
Warning (Continued)
Only your dealer or authorized
tire service center should
mount or dismount the tires.
{Warning
Mixing tires of different sizes,
tread patterns, or types on the
same axle may cause loss of
control of the vehicle, resulting
in a crash or other vehicle
damage. Use the same size,
load range, and type of tires
as the original tires.
This vehicle may have a
different size spare than the
road tires originally installed
on the vehicle. When new, the
vehicle included a spare tire
and wheel assembly with a
similar overall diameter as the
road tires and wheels, so it is
(Continued)