
Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
2019 - crc - 1/23/19
344 VEHICLE CARE
diagonal or bias ply construction;
and the letter B means belted-bias
ply construction.
(5) Rim Diameter
:Diameter of
the wheel in inches.
(6) Service Description
:These
characters represent the load
index and speed rating of the tire.
The load index represents the load
carrying capacity a tire is certified
to carry. The speed rating is the
maximum speed a tire is certified
to carry a load.
Tire Terminology and
Definitions
Air Pressure:The amount of air
inside the tire pressing outward
on each square inch of the tire.
Air pressure is expressed in kPa
(kilopascal) or psi (pounds per
square inch).
Accessory Weight
:The combined
weight of optional accessories.
Some examples of optional accessories are automatic
transmission, power windows,
power seats, and air conditioning.
Aspect Ratio
:The relationship of
a tire's height to its width.
Belt
:A rubber coated layer of
cords between the plies and the
tread. Cords may be made from
steel or other reinforcing
materials.
Bead
:The tire bead contains steel
wires wrapped by steel cords that
hold the tire onto the rim.
Bias Ply Tire
:A pneumatic tire in
which the plies are laid at
alternate angles less than
90 degrees to the centerline of the
tread.
Cold Tire Pressure
:The amount
of air pressure in a tire, measured
in kPa (kilopascal) or psi (pounds
per square inch) before a tire has
built up heat from driving. See
Tire Pressure 0346. Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the
maximum capacity of fuel, oil, and
coolant, but without passengers
and cargo.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S.
Department of Transportation
(DOT) Motor Vehicle Safety
Standards. The DOT code includes
the Tire Identification Number
(TIN), an alphanumeric designator
which can also identify the tire
manufacturer, production plant,
brand, and date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
0 197.
GAWR FRT
:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits 0197.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
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Warning (Continued)
can be used; however, use a scraper
or wire brush later to remove all
rust or dirt.
12. Remove any rust or dirt from thewheel bolts, mounting surfaces,
and spare wheel.
13. Place the compact spare tire on the wheel-mounting surface.
{Warning
Never use oil or grease on bolts or
nuts because the nuts might come
loose. The vehicle's wheel could fall
off, causing a crash.
14. Reinstall the wheel nuts. Tighten each nut by hand until the wheel
is held against the hub.
15. Lower the vehicle by turning the jack handle counterclockwise.
{Warning
Wheel nuts that are improperly or
incorrectly tightened can cause the
wheels to become loose or come off.
The wheel nuts should be tightened
with a torque wrench to the proper
torque specification after replacing.
Follow the torque specification
supplied by the aftermarket
manufacturer when using accessory
locking wheel nuts. See Capacities
(Continued)
Warning (Continued)
and Specifications 0397 for original
equipment wheel nut torque
specifications.
Caution
Improperly tightened wheel nuts
can lead to brake pulsation and
rotor damage. To avoid expensive
brake repairs, evenly tighten the
wheel nuts in the proper sequence
and to the proper torque
specification. See Capacities and
Specifications 0397 for the wheel
nut torque specification.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
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VEHICLE CARE 373
If using an automatic car wash, follow
the car wash instructions. The
windshield wiper and rear window
wiper, if equipped, must be off.
Remove any accessories that may be
damaged or interfere with the car
wash equipment.
Rinse the vehicle well, before washing
and after, to remove all cleaning
agents completely. If they are allowed
to dry on the surface, they could stain.
Dry the finish with a soft, clean
chamois or an all-cotton towel to
avoid surface scratches and water
spotting.
Finish Care
Application of aftermarket clearcoat
sealant/wax materials is not
recommended. If painted surfaces are
damaged, see your dealer to have the
damage assessed and repaired. Foreign
materials such as calcium chloride
and other salts, ice melting agents,
road oil and tar, tree sap, bird
droppings, chemicals from industrial
chimneys, etc., can damage the
vehicle's finish if they remain on
painted surfaces. Wash the vehicle assoon as possible. If necessary, use
non-abrasive cleaners that are marked
safe for painted surfaces to remove
foreign matter.
Occasional hand waxing or mild
polishing should be done to remove
residue from the paint finish. See your
dealer for approved cleaning products.
Do not apply waxes or polishes to
uncoated plastic, vinyl, rubber, decals,
simulated wood, or flat paint as
damage can occur.
Caution
Machine compounding or
aggressive polishing on a basecoat/
clearcoat paint finish may damage
it. Use only non-abrasive waxes and
polishes that are made for a
basecoat/clearcoat paint finish on
the vehicle.
To keep the paint finish looking new,
keep the vehicle garaged or covered
whenever possible. Protecting Exterior Bright Metal
Moldings
Caution
Failure to clean and protect the
bright metal moldings can result in
a hazy white finish or pitting. This
damage would not be covered by
the vehicle warranty.
The bright metal moldings on the
vehicle are aluminum, chrome,
or stainless steel. To prevent damage,
always follow these cleaning
instructions:
. Be sure the molding is cool to the
touch before applying any cleaning
solution.
. Use only approved cleaning
solutions for aluminum, chrome,
or stainless steel. Some cleaners
are highly acidic or contain
alkaline substances and can
damage the moldings.
. Always dilute a concentrated
cleaner according to the
manufacturer’s instructions.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
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376 VEHICLE CARE
Steering, Suspension, and
Chassis Components
Visually inspect steering, suspension,
and chassis components for damaged,
loose, or missing parts or signs of
wear at least once a year.
Inspect power steering for proper
attachment, connections, binding,
leaks, cracks, chafing, etc.
Visually check constant velocity joint
boots and axle seals for leaks.
Body Component Lubrication
Lubricate all key lock cylinders, hood
hinges, liftgate hinges, and the steel
fuel door hinges, unless the
components are plastic. Applying
silicone grease on weatherstrips with a
clean cloth will make them last
longer, seal better, and not stick or
squeak.
Underbody Maintenance
At least twice a year, spring and fall,
use plain water to flush any corrosive
materials from the underbody. Takecare to thoroughly clean any areas
where mud and other debris can
collect.
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 fluid. Contaminated fluid will
decrease the life of the transfer case
and/or axles and should be replaced.
Sheet Metal Damage
If the vehicle is damaged and requires
sheet metal repair or replacement,
make sure the body repair shop
applies anti-corrosion material to
parts repaired or replaced to restore
corrosion protection.
Original manufacturer replacement
parts will provide the corrosion
protection while maintaining the
vehicle warranty.
Finish Damage
Quickly repair minor chips and
scratches with touch-up materials
available from your dealer to avoidcorrosion. Larger areas of finish
damage can be corrected in your
dealer's body and paint shop.
Chemical Paint Spotting
Airborne pollutants can fall upon and
attack painted vehicle surfaces
causing blotchy, ring-shaped
discolorations, and small, irregular
dark spots etched into the paint
surface. See
“Finish Care”previously in
this section.
Interior Care
To prevent dirt particle abrasions,
regularly clean the vehicle's interior.
Immediately remove any soils.
Newspapers or dark garments can
transfer color to the vehicle’s interior.
Use a soft bristle brush to remove
dust from knobs and crevices on the
instrument cluster. Using a mild soap
solution, immediately remove hand
lotions, sunscreen, and insect
repellent from all interior surfaces or
permanent damage may result.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
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VEHICLE CARE 377
Use cleaners specifically designed for
the surfaces being cleaned to prevent
permanent damage. Apply all cleaners
directly to the cleaning cloth. Do not
spray cleaners on any switches or
controls. Remove cleaners quickly.
Before using cleaners, read and follow
all safety instructions on the label.
While cleaning the interior, open the
doors and windows to get proper
ventilation.
To prevent damage, do not clean the
interior using the following cleaners
or techniques:
.Never use a razor or any other
sharp object to remove soil from
any interior surface.
. Never use a brush with stiff
bristles.
. Never rub any surface aggressively
or with too much pressure.
. Do not use laundry detergents or
dishwashing soaps with
degreasers. For liquid cleaners, use
approximately 20 drops per 3.8 L
(1 gal) of water. A concentrated
soap solution will create streaks and attract dirt. Do not use
solutions that contain strong or
caustic soap.
. Do not heavily saturate the
upholstery when cleaning.
. Do not use solvents or cleaners
containing solvents.
Interior Glass
To clean, use a terry cloth fabric
dampened with water. Wipe droplets
left behind with a clean dry cloth.
If necessary, use a commercial glass
cleaner after cleaning with plain water.
Caution
To prevent scratching, never use
abrasive cleaners on automotive
glass. Abrasive cleaners or
aggressive cleaning may damage
the rear window defogger.
Cleaning the windshield with water
during the first three to six months of
ownership will reduce tendency to fog.
Speaker Covers
Vacuum around a speaker cover
gently, so that the speaker will not be
damaged. Clean spots with water and
mild soap.
Coated Moldings
Coated moldings should be cleaned.
. When lightly soiled, wipe with a
sponge or soft, lint-free cloth
dampened with water.
. When heavily soiled, use warm
soapy water.
Fabric/Carpet/Suede
Start by vacuuming the surface using
a soft brush attachment. If a rotating
vacuum brush attachment is being
used, only use it on the floor carpet.
Before cleaning, gently remove as
much of the soil as possible:
.Gently blot liquids with a paper
towel. Continue blotting until no
more soil can be removed.
. For solid soils, remove as much as
possible prior to vacuuming.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
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378 VEHICLE CARE
To clean:1. Saturate a clean, lint-free colorfast cloth with water.
Microfiber cloth is recommended
to prevent lint transfer to the
fabric or carpet.
2. Remove excess moisture by gently wringing until water does
not drip from the cleaning cloth.
3. Start on the outside edge of the soil and gently rub toward the
center. Fold the cleaning cloth to
a clean area frequently to
prevent forcing the soil in to the
fabric.
4. Continue gently rubbing the soiled area until there is no
longer any color transfer from
the soil to the cleaning cloth.
5. If the soil is not completely removed, use a mild soap
solution followed only by plain
water.
If the soil is not completely removed,
it may be necessary to use a
commercial upholstery cleaner or spot
lifter. Test a small hidden area for colorfastness before using a
commercial upholstery cleaner or spot
lifter. If ring formation occurs, clean
the entire fabric or carpet.
After cleaning, use a paper towel to
blot excess moisture.
Cleaning High Gloss Surfaces
and Vehicle Information and
Radio Displays
Use a microfiber cloth on high gloss
surfaces or vehicle displays. First, use
a soft bristle brush to remove dirt that
can scratch the surface. Then gently
clean by rubbing with a microfiber
cloth. Never use window cleaners or
solvents. Periodically hand wash the
microfiber cloth separately, using mild
soap. Do not use bleach or fabric
softener. Rinse thoroughly and air dry
before next use.
Caution
Do not attach a device with a
suction cup to the display. This may
cause damage and would not be
covered by the vehicle warranty.
Instrument Panel, Leather, Vinyl,
Other Plastic Surfaces, Low
Gloss Paint Surfaces, and
Natural Open Pore Wood
Surfaces
Use a soft microfiber cloth dampened
with water to remove dust and loose
dirt. For a more thorough cleaning,
use a soft microfiber cloth dampened
with a mild soap solution.
Caution
Soaking or saturating leather,
especially perforated leather, as well
as other interior surfaces, may
cause permanent damage. Wipe
excess moisture from these surfaces
after cleaning and allow them to
dry naturally. Never use heat,
steam, or spot removers. Do not use
cleaners that contain silicone or
wax-based products. Cleaners
containing these solvents can
permanently change the appearance
and feel of leather or soft trim, and
are not recommended.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
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SERVICE AND MAINTENANCE 381
Service and
Maintenance
General Information
General Information . . . . . . . . . . . . . 381
Maintenance Schedule
Maintenance Schedule . . . . . . . . . . . 383
Special Application Services
Special Application Services . . . . . 388
Additional Maintenance
and Care
Additional Maintenanceand Care . . . . . . . . . . . . . . . . . . . . . . . . . 389
Recommended Fluids,
Lubricants, and Parts
Recommended Fluids andLubricants . . . . . . . . . . . . . . . . . . . . . . . 392
Maintenance Replacement Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 393
Maintenance Records
Maintenance Records . . . . . . . . . . . . 395
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
on the vehicle. The use of flushes,
solvents, cleaners, or lubricants that
are not approved by GM could
damage the vehicle, requiring
expensive repairs that are not
covered by the vehicle warranty.
The Tire Rotation and Required
Services are the responsibility of the
vehicle owner. It is recommended to
have your dealer perform these
services every 12 000 km/7,500 mi.

Cadillac CT6 Owner Manual (GMNA-Localizing-U.S./Canada-12533370) -
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SERVICE AND MAINTENANCE 383
Maintenance Schedule
Owner Checks and Services
At Each Fuel Stop
.Check the engine oil level. See
Engine Oil 0299.
Once a Month
. Check the tire inflation pressures.
See Tire Pressure 0346.
. Inspect the tires for wear. See Tire
Inspection 0353.
. Check the windshield washer fluid
level. See Washer Fluid 0313.
Engine Oil Change
When the CHANGE ENGINE OIL
SOON message displays, have the
engine oil and filter changed within
the next 1 000 km/600 mi. If driven
under the best conditions, the engine
oil life system may not indicate the
need for vehicle service for up to a
year. The engine oil and filter must be
changed at least once a year and the
oil life system must be reset. Your
trained dealer technician can perform
this work. If the engine oil life system is reset accidentally, service the
vehicle within 5 000 km/3,000 mi since
the last service. Reset the oil life
system when the oil is changed. See
Engine Oil Life System
0302.
Air Conditioning Desiccant
(Replace 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.
Tire Rotation and Required
Services Every 12 000 km/
7,500 mi
Rotate the tires, if recommended for
the vehicle, and perform the following
services. See Tire Rotation0353.
. Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system. See Engine Oil0299
and
Engine Oil Life System 0302. .
Inspect the engine air filter and
check the air filter life percentage.
If necessary, replace engine air
filter and reset the Engine Air
Filter Life System. See Engine Air
Cleaner/Filter 0304 and
Engine Air Filter Life System 0304.
. Check engine coolant level. See
Cooling System 0307.
. Check windshield washer fluid
level. See Washer Fluid 0313.
. Check tire inflation pressures. See
Tire Pressure 0346.
. Inspect tire wear. See Tire
Inspection 0353.
. Visually check for fluid leaks.
. Inspect brake system. See Exterior
Care 0372.
. Visually inspect steering,
suspension, and chassis
components for damage, including
cracks or tears in the rubber boots,
loose or missing parts, or signs of
wear at least once a year. See
Exterior Care 0372.