
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
Service and Maintenance 467
Service and
Maintenance
General Information
General Information . . . . . . 467
Maintenance Schedule
MaintenanceSchedule . . . . . . . . . . . . . . . . . . . 469
Multi-Point Vehicle
Inspection (MPVI)
Multi-Point VehicleInspection (MPVI) . . . . . . . . 472
Special Application
Services
Special ApplicationServices . . . . . . . . . . . . . . . . . . . . 473
Recommended Fluids,
Lubricants, and Parts
Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . 474
Maintenance Replacement Parts . . . . . . 475
Maintenance Records
Maintenance Records . . . . 477
General
Information
Your vehicle is an important
investment. This section
describes the required
maintenance for the vehicle.
Follow this schedule to help
protect against major repair
expenses resulting from
neglect or inadequate
maintenance. It may also help
to maintain the value of the
vehicle if it is sold. It is the
responsibility of the owner to
have all required maintenance
performed.
Your dealer has trained
technicians who can perform
required maintenance using
genuine replacement parts.
They have up-to-date tools
and equipment for fast and
accurate diagnostics. Many
dealers have extended
evening and Saturday hours,
courtesy transportation, and
online scheduling to assist
with service needs. Your dealer recognizes the
importance of providing
competitively priced
maintenance and repair
services. With trained
technicians, the dealer is the
place for routine maintenance
such as oil changes and tire
rotations and additional
maintenance items like tires,
brakes, batteries, and wiper
blades.
Caution
Damage caused by improper
maintenance can lead to
costly repairs and may not
be covered by the vehicle
warranty. Maintenance
intervals, checks,
inspections, recommended
fluids, and lubricants are
important to keep the
vehicle in good working
condition.
Do not have chemical
flushes that are not
approved by GM performed
(Continued)

Cadillac CT4 Owner Manual (GMNA-Localizing-U.S./Canada-16500442) -
2023 - CRC - 5/4/22
472 Service and Maintenance
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.
.Change front axle fluid,
if equipped with AWD. 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.
Every 120 000 km
(75,000 mi)
.Change rear axle fluid,
without limited slip
differential. 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.
Owner Checks and
Services
Every Five Years
.Replace brake fluid every
five years. See Brake Fluid
0
398.
Every Seven Years
.Replace Air Conditioning
Desiccant every seven years.
The air conditioning system
requires maintenance every
seven years. This service
requires replacement of the
desiccant to help the
longevity and efficient
operation of the air
conditioning system. This
service can be complex. See
your dealer.
Multi-Point Vehicle
Inspection (MPVI)
A Multi Point Vehicle
Inspection (MPVI) completed
by a GM dealer technician is a
maintenance assessment of
your vehicle. The benefit of
the MPVI is to identify and
inform the customer of service
items that require immediate
attention and those that may
require attention in the future.
The technician will perform the
following checks on your
vehicle. For a complete list of
checks, inspections, and
services, see your dealer.
Some items may not apply to
your vehicle and/or region.
Diagnostics
.OnStar active, if equipped
.Service history/recall check
Engine Oil and Filter
.Engine oil
.Oil life monitor
‐ Reset oil life monitor