2023 CADILLAC CT4 winter tires

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/10/22
Driving and Operating 253
.Shift to a lower gear when
going down steep or long
hills.
{Warning
Using the brakes to slow the
vehicle on a long downhill
slope can cause brake
overheating, can reduce
brake performance, and
could result in a loss of
braking. Shift the
transmission to a lower gear
to let the engine assist the
brakes on a steep downhill
slope.
{Warning
Coasting downhill in
N (Neutral) or with the
ignition off is dangerous.
This can cause overheating
of the brakes and loss of
steering assist. Always have
the engine running and the
vehicle in gear.
.Drive at speeds that keep
the vehicle in its own lane.
Do not swing wide or cross
the center line.
.Be alert on top of hills;
something could be in your
lane (e.g., stalled car, crash).
.Pay attention to special road
signs (e.g., falling rocks area,
winding roads, long grades,
passing or no-passing zones)
and take appropriate action.
Winter Driving
Driving on Snow or IceCaution
To avoid damage to the
wheels and brake
components, always clear
snow and ice from inside the
wheels and underneath the
vehicle before driving.
Snow or ice between the tires
and the road creates less
traction or grip, so drive
carefully. Wet ice can occur at
about 0 °C (32 °F) when freezing rain begins to fall.
Avoid driving on wet ice or in
freezing rain until roads can be
treated.
For Slippery Road Driving:
.Accelerate gently.
Accelerating too quickly
causes the wheels to spin
and makes the surface under
the tires slick.
.Turn on Traction Control.
See Traction Control/
Electronic Stability Control
0
290.
.The Antilock Brake System
(ABS) improves vehicle
stability during hard stops,
but the brakes should be
applied sooner than when on
dry pavement. See Antilock
Brake System (ABS) 0286.
.Allow greater following
distance and watch for
slippery spots. Icy patches
can occur on otherwise clear
roads in shaded areas. The
surface of a curve or an
overpass can remain icy
when the surrounding roads

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
368 Vehicle Care
Vehicle Care
General Information
General Information . . . . . . 369
California PerchlorateMaterials
Requirements . . . . . . . . . . . . . 370
Accessories and Modifications . . . . . . . . . . . . . 370
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . 370
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . 371
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . 373
Engine Oil . . . . . . . . . . . . . . . . . . . . 378
Engine Oil Life System . . . 381
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Manual Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . 382
Hydraulic Clutch . . . . . . . . . . . 383
Engine Air Filter Life System . . . . . . . . . . . . . . . . . . . . . . 383
Engine Air Cleaner/ Filter . . . . . . . . . . . . . . . . . . . . . . . . . 384
Cooling System . . . . . . . . . . . . 386
Engine Overheating . . . . . . . 391 Washer Fluid . . . . . . . . . . . . . . . . 393
Brakes . . . . . . . . . . . . . . . . . . . . . . . . 393
Brake Pad Life System (If
Equipped) . . . . . . . . . . . . . . . . . . 396
Brake Fluid . . . . . . . . . . . . . . . . . . 398
Battery - North
America . . . . . . . . . . . . . . . . . . . . . 399
All-Wheel Drive . . . . . . . . . . . . 400
Park Brake and P (Park) Mechanism Check . . . . . . . 400
Wiper Blade Replacement . . . . . . . . . . . . . . 401
Windshield Replacement . . . . . . . . . . . . . . 401
Gas Strut(s) . . . . . . . . . . . . . . . . . 402
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . . . . . . . . . . . . . . . 403
Bulb Replacement
Bulb Replacement . . . . . . . . 403
Halogen Bulbs . . . . . . . . . . . . . . 403
High Intensity Discharge(HID) Lighting . . . . . . . . . . . . . 403
LED Lighting . . . . . . . . . . . . . . . . 403
Front Turn Signal Lamps . . . . . . . . . . . . . . . . . . . . . . . 404
Electrical System
Electrical SystemOverload . . . . . . . . . . . . . . . . . . . 404
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . 406
Engine Compartment
Fuse Block . . . . . . . . . . . . . . . . . 407
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 409
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . 411
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . 413
All-Season Tires . . . . . . . . . . . . 414
Winter Tires . . . . . . . . . . . . . . . . . 414
Run-Flat Tires . . . . . . . . . . . . . . . 415
Self-Sealing Tires . . . . . . . . . . 415
Low-Profile Tires . . . . . . . . . . 416
Summer Tires . . . . . . . . . . . . . . . 416
Tire Sidewall Labeling . . . . 417
Tire Designations . . . . . . . . . . 418
Tire Terminology andDefinitions . . . . . . . . . . . . . . . . . . 419
Tire Pressure . . . . . . . . . . . . . . . 422
Tire Pressure for High-Speed
Operation . . . . . . . . . . . . . . . . . . 423
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 424

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
414 Vehicle Care
Warning (Continued)
.Worn or old tires can
cause a crash. If the
tread is badly worn,
replace them.
.Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc.
.Improperly repaired
tires can cause a crash.
Only your 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.See Tire Pressure for
High-Speed Operation
0
423 for inflation pressure
adjustment for high-speed
driving.
All-Season Tires
This vehicle may come with
all-season tires. These tires
are designed to provide good
overall performance on most
road surfaces and weather
conditions. Original equipment
tires designed to GM's specific
tire performance criteria have
a TPC specification code
molded onto the sidewall.
Original equipment all-season
tires can be identified by the
last two characters of this
TPC code, which will be “MS.”
Consider installing winter tires
on the vehicle if frequent
driving on snow or ice-covered
roads is expected. All-season
tires provide adequate
performance for most winter
driving conditions, but they
may not offer the same level of traction or performance as
winter tires on snow or
ice-covered roads. See Winter
Tires
0414.
Winter Tires
This vehicle was not originally
equipped with winter tires.
Winter tires are designed for
increased traction on snow
and ice-covered roads.
Consider installing winter tires
on the vehicle if frequent
driving on ice or snow covered
roads is expected. See your
dealer for details regarding
winter tire availability and
proper tire selection. Also, see
Buying New Tires 0432.
With winter tires, there may
be decreased dry road
traction, increased road noise,
and shorter tread life. After
changing to winter tires, be
alert for changes in vehicle
handling and braking.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 415
If using winter tires:
.Use tires of the same brand
and tread type on all four
wheel positions.
.Use only radial ply tires of
the same size, load range,
and speed rating as the
original equipment tires.
Winter tires with the same
speed rating as the original
equipment tires may not be
available for H, V, W, Y, and ZR
speed rated tires. If winter
tires with a lower speed rating
are chosen, never exceed the
tire's maximum speed
capability.
Run-Flat Tires
This vehicle, when new, may
have had run-flat tires. There
is no spare tire, no tire
changing equipment, and no
place to store a tire in the
vehicle.
{Warning
While driving with run-flat
tires at a reduced inflation
pressure, avoid making
sudden stops or severe
maneuvers as the handling
capabilities of the tires will
be reduced. Driving too fast
could cause loss of control
and you or others could be
injured. Do not drive over
80 km/h (50 mph) with the
tire operating at low
pressure. Drive cautiously
and check the tire pressure
as soon as possible.
Run-flat tires can be driven up
to 80 km (50 mi) at speeds
less than 80 km/h (50 mph)
after a loss of inflation
pressure has occurred. There
is no need to stop on the side
of the road to change the tire.
The possible driving range
after a pressure loss will vary
based on the vehicle load and
driving conditions. As soon as possible, contact the nearest
authorized GM or run-flat
servicing facility for inspection
and repair or replacement.
When driving on a deflated
run-flat tire, avoid potholes
and other road hazards that
could damage the tire and/or
wheel beyond repair. When a
tire has been damaged, or if
driven any distance while
deflated, check with an
authorized run-flat tire service
center to determine whether
the tire can be repaired or
should be replaced. To
maintain the run-flat feature,
all replacement tires must be
run-flat tires.
To locate the nearest GM or
run-flat servicing facility, call
Customer Assistance.
Self-Sealing Tires
This vehicle may have
self-sealing tires. These tires
have a material inside that can
seal punctures from common
road hazards, such as nails

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
416 Vehicle Care
and screws, in the tread area.
The tire may lose air pressure
if the sidewall is damaged or
the tread puncture is too
large. If the Tire Pressure
Monitor System indicates the
tire pressure is low, inspect
the tire for damage and inflate
it to the recommended
pressure. If the tire is unable
to maintain the recommended
pressure, contact the nearest
authorized GM servicing
facility immediately for
inspection and repair or
replacement. To locate the
nearest GM servicing facility,
call GM Customer Assistance.
Caution
Do not drive on a deflated
self-sealing tire as this could
damage the tire. Make sure
the tire is inflated to the
recommended pressure or
have it immediately repaired
or replaced.When tire replacement is
needed replace with a
self-sealing tire, because the
vehicle does not come with a
spare tire or tire changing
equipment.
Low-Profile Tires
If the vehicle has
225/45R17 91V,
235/40R18 91V,
235/40R18 XL 95Y,
or 235/35R19 XL 91V,
255/35ZR18 (94Y),
or 275/35ZR18 (99Y) size
tires, they are classified as
low-profile tires.
Caution
Low-profile tires are more
susceptible to damage from
road hazards or curb impact
than standard profile tires.
Tire and/or wheel assembly
damage can occur when
coming into contact with
road hazards like potholes, (Continued)
Caution (Continued)
or sharp edged objects,
or when sliding into a curb.
The warranty does not
cover this type of damage.
Keep tires set to the correct
inflation pressure and when
possible, avoid contact with
curbs, potholes, and other
road hazards.
Summer Tires
High Performance Summer
Tires
This vehicle may come with
235/40R18 XL 95Y,
255/35ZR18 (94Y),
or 275/35ZR18 (99Y) high
performance summer tires.
These tires have a special
tread and compound that are
optimized for maximum dry
and wet road performance.
This special tread and
compound will have decreased
performance in cold climates,
and on ice and snow. It is
recommended that winter

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 417
tires be installed on the
vehicle if frequent driving at
temperatures below
approximately 5 °C (40 °F) or
on ice or snow covered roads
is expected. See Winter Tires
0414.
Caution
High performance summer
tires have rubber
compounds that lose
flexibility and may develop
surface cracks in the tread
area at temperatures below
−7 °C (20 °F). Always store
high performance summer
tires indoors and at
temperatures above −7 °C
(20 °F) when not in use. If the
tires have been subjected to
−7 °C (20 °F) or less, let them
warm up in a heated space
to at least 5 °C (40 °F) for
24 hours or more before
being installed or driving a
vehicle on which they are
installed. Do not apply heat
(Continued)
Caution (Continued)
or blow heated air directly
on the tires. Always inspect
tires before use. See Tire
Inspection0429.
Tire Sidewall Labeling
Useful information about a
tire is molded into its
sidewall. The example
shows a typical passenger
tire sidewall.
Passenger Tire Example
(1) Tire Size:The tire size
is a combination of letters
and numbers used to
define a particular tire's
width, height, aspect ratio,
construction type, and
service description. See the
“Tire Size” illustration later
in this section.
(2) TPC Spec (Tire
Performance Criteria
Specification)
:Original
equipment tires designed
to GM's specific tire
performance criteria have a
TPC specification code
molded onto the sidewall.
GM's TPC specifications
meet or exceed all federal
safety guidelines.
(3) DOT (Department of
Transportation)
:The
Department of
Transportation (DOT) code
indicates that the tire is in
compliance with the U.S.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
Vehicle Care 433
Warning (Continued)
cause injury or death.
Only your 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, tread
patterns, or types may
cause loss of vehicle
control, resulting in a
crash or other vehicle
damage. Use the correct
size, brand, and type of
tire on all 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 and cause a
crash. Use only radial-ply
tires with the wheels on
the vehicle.
Winter tires with the same
speed rating as the original
equipment tires may not be
available for H, V, W, Y and
ZR speed rated tires. Never
exceed the winter tires’
maximum speed capability
when using winter tires
with a lower speed rating.
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.
The Tire and Loading
Information label indicates
the original equipment tires
on the vehicle. See Vehicle
Load Limits
0255.
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.

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
434 Vehicle Care
{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 0432
and
Accessories and Modifications
0 370.
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