2020 CADILLAC CT6 Owner's Manual

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
328 VEHICLE CARE
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 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. The TPMS
sensor matching process should also
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 tire. 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. Place the vehicle in Service Mode. See Ignition Positions
0 183.
3. Make sure the Tire Pressure info display option is turned on. The
info displays on the DIC can be
turned on and off through the
Options menu. See Driver
Information Center (DIC) 0132.
4. Use the five-way DIC control on the right side of the steering
wheel to scroll to the Tire
Pressure screen under the DIC
info page. See Driver Information
Center (DIC) 0132.

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VEHICLE CARE 329
5. Press and hold SEL in the centerof the five-way DIC control.
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.
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 0359.
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

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
330 VEHICLE CARE
alignment. SeeWhen It Is Time for
New Tires 0330 and
Wheel Replacement 0335.
Use this rotation pattern when
rotating the tires.
Do not include the spare tire in
the tire rotation.
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 0322 and
Vehicle Load Limits 0179. Reset the Tire Pressure Monitor
System. See
Tire Pressure Monitor
Operation 0325.
Check that all wheel nuts are
properly tightened. See “Wheel
Nut Torque ”under Capacities and
Specifications 0373, and
“Removing the Flat Tire and
Installing the Spare Tire ”under
Tire Changing 0337.
{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 buildup. Do not
get grease on the wheel mounting
surface or on the wheel nuts or
bolts.
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.

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VEHICLE CARE 331
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. SeeTire
Inspection 0329 and
Tire Rotation 0329.
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) which is
molded into one side of the tire
sidewall. The first two digits represent
the week (01–52) and the last two
digits, the year. For example, the third
week of the year 2010 would have a
four-digit DOT date of 0310.Vehicle Storage
Tires age when stored normally
mounted on a parked vehicle. Park a
vehicle that will be stored for at least
a month in a cool, dry, clean area
away from direct sunlight to slow
aging. This area should be free of
grease, gasoline, or other substances
that can deteriorate rubber.
Parking for an extended period can
cause flat spots on the tires that may
result in vibrations while driving.
When storing a vehicle for at least a
month, remove the tires or raise the
vehicle to reduce the weight from the
tires.
Buying New Tires
GM has developed and matched
specific tires for the vehicle. The
original equipment tires installed
were designed to meet General
Motors Tire Performance Criteria
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. See
Tire Sidewall
Labeling 0317, for additional
information.
GM recommends replacing worn
tires in complete sets of four.
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

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
332 VEHICLE CARE
tires are not replaced at the same
time. If proper rotation and
maintenance have been done, all
four tires should wear out at
about the same time. SeeTire
Rotation 0329 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.
Winter tires with the same speed
rating as the original equipment
tires may not be available for H, V,
W, and ZR speed rated tires. Never
exceed the winter tire's maximum
speed capability when using
winter tires with a lower speed
rating.
{Warning
Tires could explode during
improper service. Attempting to
mount or dismount a tire could
cause injury or death. Only your
(Continued)
Warning (Continued)
dealer or authorized tire service
center should mount or
dismount the tires.
{Warning
Mixing tires of different sizes (other
than those originally installed on
the vehicle), brands, or types may
cause loss of control of the vehicle,
resulting in a crash or other vehicle
damage. Use the correct size, brand,
and type of tire on all four wheels.
{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
(Continued)
Warning (Continued)
and cause a crash. Use only
radial-ply tires with the wheels
on the vehicle.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size, load
range, speed rating, and
construction (radial) as the
original tires.
Vehicles that have a tire pressure
monitoring system could give an
inaccurate low-pressure warning if
non-TPC Spec rated tires are
installed. See Tire Pressure Monitor
Operation 0325.
The Tire and Loading Information
label indicates the original
equipment tires on the vehicle.
See Vehicle Load Limits 0179.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
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VEHICLE CARE 333
Different Size Tires and
Wheels
If wheels or tires are installed that are
a different size than the original
equipment wheels and tires, vehicle
performance, including its braking,
ride and handling characteristics,
stability, and resistance to rollover
may be affected. If the vehicle has
electronic systems such as antilock
brakes, rollover airbags, traction
control, electronic stability control,
or All-Wheel Drive, the performance
of these systems can also be affected.
{Warning
If different sized wheels are used,
there may not be an acceptable
level of performance and safety if
tires not recommended for those
wheels are selected. This increases
the chance of a crash and serious
injury. Only use GM specific wheel
and tire systems developed for the
vehicle, and have them properly
installed by a GM certified
technician.See
Buying New Tires 0331 and
Accessories and Modifications 0272.
Uniform Tire Quality
Grading
The following information relates
to the system developed by the
United States National Highway
Traffic Safety Administration
(NHTSA), which grades tires by
treadwear, traction, and
temperature performance. This
applies only to vehicles sold in the
United States. The grades are
molded on the sidewalls of most
passenger car tires. The 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

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
2020 - CRC - 6/11/19
334 VEHICLE CARE
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 notinclude 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 laboratory test
wheel. Sustained high temperature
can cause the material of the tire
to degenerate and reduce tire life,
and excessive temperature can
lead to sudden tire failure. The
grade C corresponds to a level of
performance which all passenger
car tires must meet under the
Federal Motor Safety Standard
No. 109. Grades B and A represent
higher levels of performance on
the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade
for this tire is established for a tirethat is properly inflated and not
overloaded. Excessive speed,
underinflation, or excessive
loading, either separately or in
combination, can cause heat
buildup and possible tire failure.
Wheel Alignment and Tire
Balance
The tires and wheels were aligned and
balanced at the factory to provide the
longest tire life and best overall
performance. Adjustments to wheel
alignment and tire balancing are not
necessary on a regular basis. Consider
an alignment check if there is unusual
tire wear or the vehicle is significantly
pulling to one side or the other. Some
slight pull to the left or right,
depending on the crown of the road
and/or other road surface variations
such as troughs or ruts, is normal.
If the vehicle is vibrating when driving
on a smooth road, the tires and
wheels may need to be rebalanced.
See your dealer for proper diagnosis.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-13566829) -
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VEHICLE CARE 335
Wheel Replacement
Replace any wheel that is bent,
cracked, or badly rusted or corroded.
If wheel nuts keep coming loose, the
wheel, wheel bolts, and wheel nuts
should be replaced. If the wheel leaks
air, replace it. Some aluminum wheels
can be repaired. See your dealer if any
of these conditions exist.
Your dealer will know the kind of
wheel that is needed.
Each new wheel should have the same
load-carrying capacity, diameter,
width, offset, and be mounted the
same way as the one it replaces.
Replace wheels, wheel bolts, wheel
nuts, or Tire Pressure Monitor System
(TPMS) sensors with new GM original
equipment parts.
{Warning
Using the wrong replacement
wheels, wheel bolts, or wheel nuts
can be dangerous. It could affect
the braking and handling of the(Continued)
Warning (Continued)
vehicle. Tires can lose air, and
cause loss of control, causing a
crash. Always use the correct wheel,
wheel bolts, and wheel nuts for
replacement.
Caution
The wrong wheel can also cause
problems with bearing life, brake
cooling, speedometer or odometer
calibration, headlamp aim, bumper
height, vehicle ground clearance,
and tire or tire chain clearance to
the body and chassis.
Used Replacement Wheels
{Warning
Replacing a wheel with a used one
is dangerous. How it has been used
or how far it has been driven may(Continued)
Warning (Continued)
be unknown. It could fail suddenly
and cause a crash. When replacing
wheels, use a new GM original
equipment wheel.
Tire Chains
Caution
Use tire chains only where legal and
only when necessary. Use low
profile chains that add no more
than 10 mm thickness to the tire
tread and inner sidewall. Use chains
that are the proper size for the tires.
Install them on the tires of the rear
axle. Do not use chains on the tires
of the front axle. Tighten them as
tightly as possible with the ends
securely fastened. Drive slowly and
follow the chain manufacturer's
instructions. If the chains contact
the vehicle, stop and retighten
them. If the contact continues, slow(Continued)