2020 GMC SIERRA Service

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 395
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 displayedon the DIC. If this warning message
is displayed, stop as soon as
possible, and inspect the
overheated trailer tire. Common
causes 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
successfully completing the
sensor learning process. See
"TTPMS Sensor Learning
Process" under Trailering App
0 310.
. One or more TTPMS sensors
are missing or damaged. The
DIC message should go off
when the TTPMS sensors are
installed and the sensor learning
process is performed
successfully. See "TTPMS
Sensor Learning Process" under
Trailering App 0310.
. Operating electronic devices or
being near facilities using radio
wave frequencies similar to the
TTPMS could cause interference
to the TTPMS which could
cause loss of signal reception
from the sensor.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
396 Vehicle Care
.If the system does not receive
the signal from an individual
sensor, an error message may
not occur until the vehicle has
been driver for a period of time.
If the TTPMS is not functioning
properly, it cannot detect or signal a
low tire condition. See your dealer
for service if the DIC message
comes on and stays on when the
trailer tire pressures have been
checked and determined to be
correct.
Tire Inspection
We recommend that the tires,
including the spare tire, if the
vehicle has one, be inspected
for signs of wear or damage at
least once a month.
Replace the tire if:
.The indicators at three or
more places around the tire
can be seen.
.There is cord or fabric
showing through the tire's
rubber.
.The tread or sidewall is
cracked, cut, or snagged
deep enough to show cord or
fabric.
.The tire has a bump, bulge,
or split.
.The tire has a puncture, cut,
or other damage that cannot
be repaired well because of
the size or location of the
damage.
Tire Rotation
Tires should be rotated every
12 000 km (7,500 mi). See
Maintenance Schedule 0442.
Tires are rotated to achieve a
more uniform wear for all tires.
The first rotation is the most
important. Anytime unusual wear is
noticed, rotate the tires as soon
as possible, check for proper tire
inflation pressure, and check for
damaged tires or wheels. If the
unusual wear continues after the
rotation, check the wheel
alignment. See
When It Is Time
for New Tires 0398 and
Wheel Replacement 0403.
Use this rotation pattern when
rotating the tires if the vehicle
has single rear wheels.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 397
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
0 459 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 0442.{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 - 4/10/19
400 Vehicle Care
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.
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.
(Continued)
Warning (Continued)
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
all right to drive on it. The
spare tire was developed for
use on this vehicle and will not
affect vehicle handling.
{Warning
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
after many miles of driving.
A tire and/or wheel could fail
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
402 Vehicle Care
Uniform Tire Quality Grading
(UTQG) system does not apply
to deep tread, winter tires,
compact spare tires, tires with
nominal rim diameters of
10 to 12 inches (25 to 30 cm),
or to some limited-production
tires.
While the tires available on
General Motors passenger cars
and light trucks may vary with
respect to these grades, they
must also conform to federal
safety requirements and
additional General Motors Tire
Performance Criteria (TPC)
standards.
Quality grades can be found
where applicable on the tire
sidewall between tread shoulder
and maximum section width. For
example:Treadwear 200 Traction AA
Temperature A
All Passenger Car Tires Must
Conform to Federal Safety
Requirements In Addition To
These Grades.
Treadwear
The treadwear grade is a
comparative rating based on the
wear rate of the tire when tested
under controlled conditions on a
specified government test
course. For example, a tire
graded 150 would wear one and
one-half (1½) times as well on
the government course as a tire
graded 100. The relative
performance of tires depends
upon the actual conditions of
their use, however, and may
depart significantly from the
norm due to variations in driving
habits, service practices and
differences in road
characteristics and climate.Traction
The traction grades, from
highest to lowest, are AA, A, B,
and C. Those grades represent
the tire's ability to stop on wet
pavement as measured under
controlled conditions on
specified government test
surfaces of asphalt and
concrete. A tire marked C may
have poor traction performance.
Warning: The traction grade
assigned to this tire is based on
straight-ahead braking traction
tests, and does not include
acceleration, cornering,
hydroplaning, or peak traction
characteristics.
Temperature
The temperature grades are A
(the highest), B, and C,
representing the tire's resistance
to the generation of heat and its
ability to dissipate heat when
tested under controlled
conditions on a specified indoor

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
Vehicle Care 405
Caution
Use tire chains only where legal
and only when necessary. Use
chains that are the proper size for
the tires. If the vehicle has 265/
70R17 or 265/65R18 size tires,
they may be installed on the tires
of the rear axle only. If the vehicle
is a dual rear wheel model and
has LT235/80R17 tires, chains
may be installed on the tires of
the rear axle only. If the vehicle
has 255/70R17, LT245/75R17,
or LT275/70R18 size tires, they
may be installed on the tires of
the front and rear axle. If the
vehicle is a 2500 Series with
LT265/70R17 size tires, chains
may be installed on the tires of
both the front and rear axle.
Tighten them as tightly as
possible with the ends securely
fastened. Drive slowly and follow
the chain manufacturer's
instructions. If you can hear the(Continued)
Caution (Continued)
chains contacting the vehicle,
stop and retighten them. If the
contact continues, slow down
until it stops. Driving too fast or
spinning the wheels with chains
on will damage the vehicle.
If a Tire Goes Flat
It is unusual for a tire to blowout
while driving, especially if the tires
are maintained properly. If air goes
out of a tire, it is much more likely to
leak out slowly. But if there ever is a
blowout, here are a few tips about
what to expect and what to do:
If a front tire fails, the flat tire
creates a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer to
maintain lane position, and then
gently brake to a stop, well off the
road, if possible. A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction as
used in a skid. Stop pressing the
accelerator pedal and steer to
straighten the vehicle. It may be
very bumpy and noisy. Gently brake
to a stop, well off the road,
if possible.
{Warning
Driving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has been
driven on while severely
underinflated or flat may cause a
blowout and a serious crash.
Never attempt to re-inflate a tire
that has been driven on while
severely underinflated or flat.
Have your dealer or an authorized
tire service center repair or
replace the flat tire as soon as
possible.

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
414 Vehicle Care
{Warning
Wheel nuts that are improperly or
incorrectly tightened can cause
the wheels to become loose or
come off. The wheel nuts should
be tightened with a torque wrench
to the proper torque specification
after replacing. Follow the torque
specification supplied by the
aftermarket manufacturer when
using accessory locking wheel
nuts. SeeCapacities and
Specifications 0459 for original
equipment wheel nut torque
specifications.
Caution
Improperly tightened wheel nuts
can lead to brake pulsation and
rotor damage. To avoid expensive
brake repairs, evenly tighten the
wheel nuts in the proper
sequence and to the proper
(Continued)
Caution (Continued)
torque specification. See
Capacities and Specifications
0459 for the wheel nut torque
specification.
13. Tighten the nuts firmly in a crisscross sequence, as
shown, by turning the wheel
wrench clockwise.
For vehicles with dual wheels, have
a technician check the wheel nut
tightness of all wheels with a torque
wrench after the first 160, 1 600 and
10 000 km (100, 1,000 and 6,000 mi).
Repeat this service whenever you have a tire removed or serviced.
See
Capacities and Specifications
0 459.
When reinstalling the regular wheel
and tire, also reinstall either the
center cap, or bolt-on hub cap,
depending on what the vehicle is
equipped with. For center caps,
place the cap on the wheel and tap
it into place until it seats flush with
the wheel. The cap only goes on
one way. Be sure to line up the tab
on the center cap with the
indentation on the wheel. For
bolt-on hub caps, align the plastic
nut caps with the wheel nuts and
then tighten by hand. Then use the
wheel wrench to tighten.
Storing a Flat or Spare Tire
and Tools
{Warning
Storing a jack, a tire, or other
equipment in the passenger
compartment of the vehicle could
cause injury. In a sudden stop or (Continued)

GMC Sierra/Sierra Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13337776) - 2020 - CRC - 4/10/19
418 Vehicle Care
If equipped with a spare tire
cable, reattach the clip to the
frame attachment bracket. Note
that there may be slack in the
cable.
Repeat this tightness check
procedure when checking the
spare tire pressure according
to the scheduled maintenance
information or any time the
spare tire is handled due to
service of other components.Correctly Stored
Incorrectly Stored
10. Reinstall the spare tire lock, if the vehicle has one.
Return the jack and tools to their
original location in the vehicle. See
“Removing the Spare Tire and
Tools.”
Full-Size Spare Tire
If this vehicle came with a full-size
spare tire, it was fully inflated when
new, however, it can lose air over
time. Check the inflation pressure
regularly. See Tire Pressure0387
and
Vehicle Load Limits 0200. For
instructions on how to remove,
install, or store a spare tire, see Tire
Changing 0407.
If equipped with a temporary use
full-size spare tire, it is indicated on
the tire sidewall. See Tire Sidewall
Labeling 0381. This spare tire