2021 CADILLAC CT4 tire size

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
356 VEHICLE CARE
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 0354 and
Accessories and Modifications 0306.
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
government course as a tire

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
358 VEHICLE CARE
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
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
be unknown. It could fail suddenly
and cause a crash. When replacing
wheels, use a new GM original
equipment wheel.
Tire Chains
{Warning
If the vehicle has 235/40R18 or
235/35R19 size tires, do not use tire
chains. There is not enough
clearance. Tire chains used on a
vehicle without the proper amount
of clearance can cause damage to
the brakes, suspension, or other
vehicle parts. The area damaged by
the tire chains could cause loss of
control and a crash. Use another
type of traction device only if its
manufacturer recommends it for
the vehicle's tire size combination
and road conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the traction
device if it contacts the vehicle. Do
not spin the wheels. If traction
devices are used, install them on
the rear tires.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
VEHICLE CARE 359
Caution
If the vehicle is equipped with a
tire size other than 235/40R18 or
235/35R19, use tire chains only
where legal and only when
necessary. Use low profile chains
that add no more than 12 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.
Don't 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
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 blow out
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. SeeTires0339 for
additional information. 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.
If the vehicle has run-flat tires, there
is no need to stop on the side of the
road to change a flat tire. See Run-Flat
Tires 0340.
{Warning
Special tools and procedures are
required to service a run-flat tire.
If these special tools and
procedures are not used, injury or
vehicle damage may occur. Always
(Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
SERVICE AND MAINTENANCE 385
Footnotes—Maintenance Schedule
Additional Required Services -
Normal
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0352.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) 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 0316.
(4) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition. (5)
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 transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(6) Or every five years, whichever
comes first. See Cooling System0317.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0325.
(9) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0327.
(10) Or every 10 years, whichever
comes first. See Gas Strut(s)0328.
(11) Replace air conditioning
desiccant every seven years.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
388 SERVICE AND MAINTENANCE
Footnotes—Maintenance Schedule
Additional Required Services -
Severe
(1) Vehicles with different size front
and rear tires do not have tire
rotation. See Tire Rotation0352.
(2) Or every two years, whichever
comes first. More frequent passenger
compartment air filter replacement
may be needed if driving in areas with
heavy traffic, poor air quality, high
dust levels, or environmental
allergens. Passenger compartment air
filter replacement may also be needed
if there is reduced airf low, window
fogging, or odors. Your GM dealer can
help determine when to replace the
filter.
(3) 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 0316.
(4) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition. (5)
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 transfer case fluid. Contaminated
fluid will decrease the life of the
transfer case and/or axles and should
be replaced.
(6) Or every five years, whichever
comes first. See Cooling System0317.
(7) Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(8) Replace brake fluid every five
years. See Brake Fluid 0325.
(9) Or every 10 years, whichever
comes first. See Gas Strut(s)0328.
(10) Replace air conditioning
desiccant every seven years.Special Application
Services
.Severe Commercial Use Vehicles
Only: Lubricate chassis components
every oil change.
.Have underbody flushing service
performed. See "Underbody
Maintenance" in Exterior Care0370.
Additional Maintenance
and Care
Your vehicle is an important
investment and caring for it properly
may help to avoid future costly
repairs. To maintain vehicle
performance, additional maintenance
services may be required.
It is recommended that your dealer
perform these services —their trained
dealer technicians know your vehicle
best. Your dealer can also perform a
thorough assessment with a
multi-point inspection to recommend
when your vehicle may need
attention.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
INDEX 431
Thigh Support Adjustment . . . . . . . . . . 33
Time . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 84
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 339All-Season . . . . . . . . . . . . . . . . . . . . . . . . . 339
Buying New Tires . . . . . . . . . . . . . . . . . 354
Chains . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 358
Designations . . . . . . . . . . . . . . . . . . . . . . 343
Different Size . . . . . . . . . . . . . . . . . . . . . . 356
If a Tire Goes Flat . . . . . . . . . . . . . . . . 359
Inspection . . . . . . . . . . . . . . . . . . . . . . . . . 352
Low Profile . . . . . . . . . . . . . . . . . . . . . . . . 341
Pressure . . . . . . . . . . . . . . . . . . . . . 346, 347
Pressure Light . . . . . . . . . . . . . . . . . . . . . 104
Pressure Monitor Operation . . . . . . 349
Pressure Monitor System . . . . . . . . 348
Rotation . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Run-Flat . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Sealant and Compressor Kit . . . . . 360
Sealant and Compressor Kit,Storing . . . . . . . . . . . . . . . . . . . . . . . . . . . 366
Self-Sealing . . . . . . . . . . . . . . . . . . . . . . . . 341
Sidewall Labeling . . . . . . . . . . . . . . . . . 342
Terminology and Definitions . . . . 344
Uniform Tire Quality Grading . . . . 356
Wheel Alignment and Tire
Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 357
Wheel Replacement . . . . . . . . . . . . . . 357 Tires (cont'd)
When It Is Time for New
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 353
Winter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 340
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . 293
Towing Driving Characteristics . . . . . . . . . . . 297
Equipment . . . . . . . . . . . . . . . . . . . . . . . . 302
General Information . . . . . . . . . . . . . . 297
Recreational Vehicle . . . . . . . . . . . . . . 370
Trailer . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300
Vehicle . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Track Events and Competitive Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 207
Traction Control System
(TCS)/StabiliTrak Light . . . . . . . . . 103
Limited-Slip Differential . . . . . . . . . . 248
Off Light . . . . . . . . . . . . . . . . . . . . . . . . . . . 102
Traction Control/Electronic Stability Control . . . . . . . . . . . . . . . . . . . 239
Trademarks and License Agreements . . . . . . . . . . . . . . . . . . . . . . . . 187
Trailer Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 300 Transmission
Automatic . . . . . . . . . . . . . . . . . . . 227, 229
Fluid, Automatic . . . . . . . . . . . . . . . . . . 315
Transportation Program, Courtesy . . . . . . . . . . . . . . . . . . . . . . . . . . . 405
Trip Odometer . . . . . . . . . . . . . . . . . . . . . . . 93
Trunk . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19
Turn and Lane-Change Signals . . . . 129
U
Umbrella Storage . . . . . . . . . . . . . . . . . . . . 79
Uniform Tire Quality Grading . . . . . . 356
Universal Remote System . . . . . . . . . . 122 Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 124
Programming . . . . . . . . . . . . . . . . . . . . . . 122
Updates Map Data . . . . . . . . . . . . . . . . . . . . . . . . . . 163
Software . . . . . . . . . . . . . . . . . . . . . . . . . . . 140
USB Port . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 145
Using the Navigation System . . . . . . 150
Using the System . . . . . . . . . . . . . . . . . . . 137
Using This Manual . . . . . . . . . . . . . . . . . . . . 2

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-14584335) -
2021 - CRC - 11/23/20
432 INDEX
V
VehicleAlarm System . . . . . . . . . . . . . . . . . . . . . . 20
Automatic Hold Light . . . . . . . . . . . . 101
Canadian Owners . . . . . . . . . . . . . . . . . . . . 1
Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . 204
Identification Number (VIN) . . . . . 395
Load Limits . . . . . . . . . . . . . . . . . . . . . . . 214
Messages . . . . . . . . . . . . . . . . . . . . . . . . . . 116
Personalization . . . . . . . . . . . . . . . . . . . 117
Remote Start . . . . . . . . . . . . . . . . . . . . . . . 13
Security . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 20
Speed Messages . . . . . . . . . . . . . . . . . . . 117
Towing . . . . . . . . . . . . . . . . . . . . . . . . . . . . 369
Vehicle Ahead Indicator . . . . . . . . . . . . 102
Vehicle Care Storing the Tire Sealant andCompressor Kit . . . . . . . . . . . . . . . . . . 366
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 346
Vehicle Data Recording and Privacy . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 410
Vehicle Hold Automatic . . . . . . . . . . . . . . . . . . . . . . . . . 239
Vehicle Hold (AVH)
Automatic . . . . . . . . . . . . . . . . . . . . . . . . . 239
Vehicle Positioning . . . . . . . . . . . . . . . . . 162
Ventilation, Air . . . . . . . . . . . . . . . . . . . . . 200 Visors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
Voice Recognition . . . . . . . . . . . . . . . . . . 163
W
Warning
Brake System Light . . . . . . . . . . . . . . . . 99
Caution and Danger . . . . . . . . . . . . . . . . . 2
Warning Lights, Gauges, and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . 87
Warnings Hazard Flashers . . . . . . . . . . . . . . . . . . . 129
Washer Fluid . . . . . . . . . . . . . . . . . . . . . . . . 323
Wheels
Alignment and Tire Balance . . . . . 357
Different Size . . . . . . . . . . . . . . . . . . . . . . 356
Replacement . . . . . . . . . . . . . . . . . . . . . . 357
When It Is Time for New Tires . . . . 353
Where to Put the Restraint . . . . . . . . . 64
Windows . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Power . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
Windshield
Replacement . . . . . . . . . . . . . . . . . . . . . . 328
Wiper/Washer . . . . . . . . . . . . . . . . . . . . . . 82
Winter Driving . . . . . . . . . . . . . . . . . . . . . . . . . . . . 213
Winter Tires . . . . . . . . . . . . . . . . . . . . . . . . . 340
Wiper Blade Replacement . . . . . . . . . . 327
Wireless Charging . . . . . . . . . . . . . . . . . . . 85