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High Speed Operation Inflation Pressures
Tire Size Cold Inflation Pressure kPa (psi)
255/35ZR18 (94Y) 300 kPa (44 psi) Front
275/35ZR18 (99Y) 300 kPa (44 psi) Rear
225/45R17 91V 240 kPa (35 psi) Front
225/45R17 91V 280 kPa (41 psi) Rear
235/40R18 91V 250 kPa (36 psi) Front
235/40R18 91V 280 kPa (41 psi) Rear
235/40R18 95Y 300 kPa (44 psi) Front
235/40R18 95Y 340 kPa (49 psi) Rear
235/35R19 91V 270 kPa (39 psi) Front
235/35R19 91V 320 kPa (46 psi) Rear
Return the tires to the
recommended cold tire
inflation pressure when
high-speed driving has ended.
See Vehicle Load Limits0255
and
Tire Pressure 0422.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
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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
energy efficiency and tire
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 tomaintain 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
variety of 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
0425.
See Radio Frequency
Statement 0494.
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
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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 Limits0255.
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.
Using the DIC, tire pressure
levels can be viewed. For
additional information and
details about the DIC
operation and displays see
Driver Information Center
(DIC) (Base Level)
0129 or
Driver Information Center
(DIC) (Uplevel) 0132.
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, attached to
your vehicle, shows the size of
the original equipment tires
and the correct inflation
pressure for the tires when
they are cold. See Vehicle
Load Limits 0255, for an
example of the Tire and Loading Information label and
its location. Also see Tire
Pressure
0422.
The TPMS can warn about a
low tire pressure condition but
it does not replace normal tire
maintenance. See Tire
Inspection 0429, Tire Rotation
0 429, and Tires 0413.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.
Factory-installed Tire Inflator
Kits use a GM-approved liquid
tire sealant. Using
non-approved tire sealants
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could damage the TPMS
sensors. See Tire Sealant and
Compressor Kit0439 for
information regarding the
inflator kit materials and
instructions.
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 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 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
0432.
.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.
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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 (Continued)
Warning (Continued)
maximum pressure listed on
the tire sidewall. See Tire
Sidewall Labeling 0417 and
Vehicle Load Limits 0255.
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.
The TPMS will not activate the
tire fill alert properly under the
following conditions:
.There is interference from
an external device or
transmitter.
.The air pressure from the
inflation device is not
sufficient to inflate the tire.
.There is a malfunction in
the TPMS.
.There is a malfunction in the
horn or turn signal lamps.
.The identification code of
the TPMS sensor is not
registered to the system.
.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
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tire fill alert feature is not
working, use a tire pressure
gauge.
TPMS Sensor Matching
Process—Auto Learn
Function
Each TPMS sensor has a
unique identification code. The
identification code needs to be
matched to a new tire/wheel
position after rotating the
tires or replacing one or more
of the TPMS sensors. When a
tire is installed, the vehicle
must be stationary for about
20 minutes before the system
recalculates. The following
relearn process takes up to
10 minutes, driving at a
minimum speed of 20 km/h
(12 mph). A dash (-) or pressure
value will display in the DIC.
See Driver Information Center
(DIC) (Base Level) 0129 or
Driver Information Center
(DIC) (Uplevel) 0132. A warning
message displays in the DIC if
a problem occurs during the
relearn process.
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
according to the interval
specified in the
Maintenance Schedule. See
Maintenance Schedule
0 469.
Tires are rotated to
achieve a 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 0431
and
Wheel Replacement 0436.
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Use this rotation pattern if
the vehicle has different
size tires on the front
and rear.
Different tire sizes should
not be rotated front
to rear.Use this rotation pattern
when rotating tires of the
same size installed on all
four wheel positions.
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 Pressure0422
and
Vehicle Load Limits 0255. Reset the Tire Pressure
Monitor System. See Tire
Pressure Monitor
Operation
0425.
Check that all wheel nuts
are properly tightened. See
“Wheel Nut Torque” under
Capacities and
Specifications 0480.
{Warning
Rust or dirt on a wheel,
or on the parts to which it
is fastened, can cause
wheel nuts to become
loose over 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
paper towel can be used;
(Continued)
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Warning (Continued)
however, use a scraper
or wire brush later to
remove all rust or dirt.
Lightly coat the center of
the wheel hub with wheel
bearing grease after a
wheel change or tire
rotation to prevent
corrosion or rust build-up.
{Warning
Do not apply grease to
the wheel mounting
surface, wheel conical
seats, or the wheel nuts
or bolts. Grease applied
to these areas could
cause a wheel to become
loose or come off,
resulting in a crash.
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.
Treadwear indicators are one
way to tell when it is time for
new tires. Treadwear
indicators appear when the
tires have only 1.6 mm (1/16 in)
or less of tread remaining. See
Tire Inspection 0429 and
Tire Rotation 0429. The rubber in tires ages over
time. This also applies to the
spare tire, if the vehicle has
one, even if it is never used.
Multiple factors including
temperatures, loading
conditions, and inflation
pressure maintenance affect
how fast aging takes place.
GM recommends that tires,
including the spare if
equipped, be replaced after six
years, regardless of tread
wear. To identify the age of a
tire, use the tire manufacture
date, which is the last four
digits of the DOT Tire
Identification Number (TIN)
molded into one side of the
tire sidewall. The last four
digits of the TIN indicate the
tire manufactured date. The
first two digits represent the
week and the last two digits,
the year. For example, the
third week of the year 2020
would have a 4-digit DOT date
of 0320. Week 01 is the first
full week (Sunday through
Saturday) of each year.