2021 CADILLAC XT6 service

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
282 DRIVING AND OPERATING
signal is activated in the same
direction as a detected vehicle, this
display will flash as an extra warning
not to change lanes.
LCA can be disabled through vehicle
personalization. When you disable
LCA, SBZA is also disabled. SeeVehicle
Personalization 0130. If LCA is
disabled by the driver, the LCA mirror
displays will not light up.
When the System Does Not
Seem to Work Properly
The LCA system requires some driving
for the system to calibrate to
maximum performance. This
calibration may occur more quickly if
the vehicle is driving on a straight
highway road with traffic and roadside
objects (e.g., guardrails, barriers).
LCA displays may not come on when
passing a vehicle quickly, for a
stopped vehicle, or when towing a
trailer. The LCA detection zones that
extend back from the side of the
vehicle do not move further back
when a trailer is towed. Use caution
while changing lanes when towing a
trailer. LCA may alert to objects attached to the vehicle, such as a
trailer, bicycle, or object extending out
to either side of the vehicle. Attached
objects may also interfere with the
detection of vehicles. This is normal
system operation; the vehicle does not
need service.
LCA may not always alert the driver to
vehicles in the next lane over,
especially in wet conditions or when
driving on sharp curves. The system
does not need to be serviced. The
system may light up due to guardrails,
signs, trees, shrubs, and other
non-moving objects. This is normal
system operation; the vehicle does not
need service.
LCA may not operate when the LCA
sensors in the left or right corners of
the rear bumper are covered with
mud, dirt, snow, ice, or slush, or in
heavy rainstorms. For cleaning
instructions, see "Washing the
Vehicle" under
Exterior Care0370.
If the DIC still displays the system
unavailable message after cleaning
both sides of the vehicle toward the
rear corners of the vehicle, see your
dealer. If the LCA displays do not light up
when moving vehicles are in the side
blind zone or are rapidly approaching
this zone and the system is clean, the
system may need service. Take the
vehicle to your dealer.
Radio Frequency Information
See
Radio Frequency Statement 0406.
Lane Keep Assist (LKA)
If equipped, LKA may help avoid
crashes due to unintentional lane
departures. This system uses a camera
to detect lane markings between
60 km/h (37 mph) and 180 km/h
(112 mph). It may assist by gently
turning the steering wheel if the
vehicle approaches a detected lane
marking. It may also provide a Lane
Departure Warning (LDW) alert if the
vehicle crosses a detected lane
marking. LKA can be overridden by
turning the steering wheel. This
system is not intended to keep the
vehicle centered in the lane. LKA will
not assist and alert if the turn signal
is active in the direction of lane

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
284 DRIVING AND OPERATING
three times, on the right or left,
depending on the lane departure
direction.
Take Steering
The LKA system does not
continuously steer the vehicle. If LKA
does not detect active driver steering,
an alert and chime may be provided.
Steer the vehicle to dismiss. LKA may
become temporarily unavailable after
repeated take steering alerts.
When the System Does Not
Seem to Work Properly
The system performance may be
affected by:
.Close vehicles ahead.
.Sudden lighting changes, such as
when driving through tunnels.
.Banked roads.
.Roads with poor lane markings,
such as two-lane roads.
If the LKA system is not functioning
properly when lane markings are
clearly visible, cleaning the windshield
may help. A camera blocked message may
display if the camera is blocked. Some
driver assistance systems may have
reduced performance or not work at
all. An LKA or LDW unavailable
message may display if the systems
are temporarily unavailable. This
message could be due to a blocked
camera. The LKA system does not
need service. Clean the outside of the
windshield behind the rearview mirror.
LKA assistance and/or LDW alerts
may occur due to tar marks, shadows,
cracks in the road, temporary or
construction lane markings, or other
road imperfections. This is normal
system operation; the vehicle does not
need service. Turn LKA off if these
conditions continue.
Surround Vision Recorder
If equipped, this system records the
360° camera views to an SD card. Only
images are recorded, no sound. An SD
card will be needed for this system.
The recommended SD card is a 32GB
SDHC card with FAT32 file system,
Class 10 and over.
Insert the SD card into the card reader
in the trim panel of the left-hand rear
seat. Disable the system from the
playback screen before removing the
SD card from the reader. Do not
remove the card while recording is
enabled. This could corrupt the video
file and/or the SD card.
Other files should not be stored on
the same SD card as the surround
vision recorder files. Storing other files
on the same card may increase
recording start up and playback time
or result in a loss of data.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
286 DRIVING AND OPERATING
message may be displayed if no
surround vision recorded video file is
available for playback.
Fuel
Top Tier Fuel
GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine
clean, reduce engine deposits, and
maintain optimal vehicle performance.
Look for the TOP TIER Logo or see
www.toptiergas.com for a list of TOP
TIER Detergent Gasoline marketers
and applicable countries.
Recommended Fuel (2.0L
L4 Turbo Engine)
Premium unleaded gasoline meeting
ASTM specification D4814 with a
posted octane rating of 93—(R+M)/2
— is highly recommended for best
performance and fuel economy.
Unleaded gasoline with an octane
rated as low as 87 can be used. Using
unleaded gasoline rated below
93 octane, however, will lead to
reduced acceleration and fuel
economy. If knocking occurs, use a
gasoline rated at 93 octane as soon as
possible, otherwise, the engine could
be damaged. If heavy knocking is
heard when using gasoline with a
93 octane rating, the engine needs
service. Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
Recommended Fuel (3.6L
V6 Engine)
Use regular unleaded gasoline meeting
ASTM specification D4814 with a
posted octane rating of 87
—(R+M)/2
— or higher. Do not use gasoline with
a posted octane rating of less than 87,
as this may cause engine knock and
will lower fuel economy.
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
DRIVING AND OPERATING 293
.Shift into a gear.
.Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the chocks.
4. Stop and have someone pick up and store the chocks.
Maintenance When Trailer
Towing
The vehicle needs service more often
when used to tow trailers. See
Maintenance Schedule 0380. It is
especially important to check the
transmission for fluid leaks, engine
oil, axle lubricant, belts, cooling
system, and brake system before and
during each trip.
Check periodically that all nuts and
bolts on the trailer hitch are tight.
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. See Engine Overheating
0 320.
Trailer Towing
Caution
Towing a trailer improperly can
damage the vehicle and result in
costly repairs not covered by the
vehicle warranty. To tow a trailer
correctly, follow the directions in
this section and see your dealer for
important information about
towing a trailer with the vehicle.
Trailer Weight
{Warning
Never exceed the towing capacity
for your vehicle.
Safe trailering requires monitoring the
weight, speed, altitude, road grades,
outside temperature, dimensions of
the front of the trailer, and how
frequently the vehicle is used to tow a
trailer.
Trailer Weight Ratings
When towing a trailer, the combined
weight of the vehicle, vehicle contents,
trailer, and trailer contents must be
below all of the maximum weight
ratings for the vehicle including:
.GCWR: Gross Combined Weight
Rating
.GVWR: Gross Vehicle Weight Rating
.Maximum Trailer Weight Rating
.Maximum Trailer Tongue Weight
See “Weight-Distributing Hitch
Adjustment ”under Towing Equipment
0 297 to determine if equalizer bars
are required to obtain the maximum
trailer weight rating.
See “Trailer Brakes ”under Towing
Equipment 0297 to determine if
brakes are required based on your
trailer's weight.
The only way to be sure the weight is
not exceeding any of these ratings is
to weigh the tow vehicle and trailer
combination, fully loaded for the trip,
getting individual weights for each of
these items.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
300 DRIVING AND OPERATING
controller as part of the trailer wiring
package. The harness contains the
following circuits:Electric Trailer
Brakes Blue
Battery Feed Red/Black or
Red/Blue
Brake Apply
Signal White/Blue
Ground Black or White
Refer to the aftermarket electric trailer
brake controller owner's manual to
determine wire color coding of the
electric trailer brake controller. The
wire colors on the brake controller
may be different from the vehicle.
It may be necessary to have a
technician connect the 12-volt power
to the engine compartment fuse block.
The electric trailer brake controller
should be installed by your dealer or a
qualified service center.
Trailer Lamps
Always check that all trailer lamps are
working at the beginning of each trip,
and periodically on longer trips.
Turn Signals When Towing a
Trailer
When properly connected, the trailer
turn signals should illuminate to
indicate the vehicle is turning,
changing lanes, or stopping. When
towing a trailer, the arrows on the
instrument cluster will illuminate
even if the trailer is not properly
connected or the bulbs are
burned out.
Trailer Sway Control (TSC)
Vehicles with StabiliTrak/Electronic
Stability Control (ESC) have a Trailer
Sway Control (TSC) feature. Trailer
sway is unintended side-to-side
motion of a trailer while towing. If the
vehicle is towing a trailer and the TSC
detects that sway is increasing, the
vehicle brakes are selectively applied
to help reduce excessive trailer sway.
If equipped with the Integrated Trailer
Brake Control (ITBC) system, and the
trailer has an electric brake system,
StabiliTrak/ESC may also apply the
trailer brakes.
If TSC is enabled, the Traction Control
System (TCS)/StabiliTrak/ESC warning
light will flash on the instrument
cluster. Reduce vehicle speed by
gradually removing your foot from the
accelerator pedal. If trailer sway
continues, StabiliTrak/ESC can reduce
engine torque to help slow the vehicle.
TSC will not function if StabiliTrak/
ESC is turned off. See Traction Control/
Electronic Stability Control 0248.
{Warning
Trailer sway can result in a crash
and in serious injury or death, even
if the vehicle is equipped with TSC.
If the trailer begins to sway, reduce
vehicle speed by gradually removing
your foot from the accelerator. Then
pull over to check the trailer and
vehicle to help correct possible
(Continued)

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
DRIVING AND OPERATING 301
Warning (Continued)
causes, including an improperly or
overloaded trailer, unrestrained
cargo, improper trailer hitch
configuration, or improperly
inflated or incorrect vehicle or
trailer tires. SeeTowing Equipment
0 297 for trailer ratings and hitch
setup recommendations.
Trailer Tires
Special Trailer (ST) tires differ from
vehicle tires. Trailer tires are designed
with stiff sidewalls to help prevent
sway and to support heavy loads.
These features can make it difficult to
determine if the trailer tire pressures
are low only based on a visual
inspection.
Always check all trailer tire pressures
before each trip when the tires are
cool. Low trailer tire pressure is a
leading cause of trailer tire blowouts. Trailer tires deteriorate over time. The
trailer tire sidewall will show the week
and year the tire was manufactured.
Many trailer tire manufacturers
recommend replacing tires more than
six years old.
Overloading is another leading cause
of trailer tire blowouts. Never load the
trailer with more weight than the tires
are designed to support. The load
rating is on the trailer tire sidewall.
Always know the maximum speed
rating for the trailer tires before
driving. This may be significantly
lower than the vehicle tire speed
rating. The speed rating may be on
the trailer tire sidewall. If the speed
rating is not shown, the default trailer
tire speed rating is 105 km/h (65 mph).
Conversions and
Add-Ons
Add-On Electrical
Equipment
{Warning
The Data Link Connector (DLC) is
used for vehicle service and
Emission Inspection/Maintenance
testing. See
Malfunction Indicator
Lamp (Check Engine Light) 0115.
A device connected to the DLC —
such as an aftermarket fleet or
driver-behavior tracking device —
may interfere with vehicle systems.
This could affect vehicle operation
and cause a crash. Such devices
may also access information stored
in the vehicle’s systems.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
VEHICLE CARE 303
Vehicle Care
General Information
General Information . . . . . . . . . . . . . 304
California Proposition65 Warning . . . . . . . . . . . . . . . . . . . . . 304
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . . . . . 305
Accessories and Modifications . . . . . . . . . . . . . . . . . . . 305
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . . . . . 305
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 306
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . . . . . . 308
Engine Oil . . . . . . . . . . . . . . . . . . . . . . . . . 311
Engine Oil Life System . . . . . . . . . . . 313
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 314
Engine Air Filter Life System . . . . 314
Engine Air Cleaner/Filter . . . . . . . . . 315
Cooling System . . . . . . . . . . . . . . . . . . . 316
Engine Overheating . . . . . . . . . . . . . . 320
Washer Fluid . . . . . . . . . . . . . . . . . . . . . 321
Brakes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 322
Brake Fluid . . . . . . . . . . . . . . . . . . . . . . . 322 Battery - North America . . . . . . . . . 323
All-Wheel Drive . . . . . . . . . . . . . . . . . . 324
Park Brake and P (Park)
Mechanism Check . . . . . . . . . . . . . . 324
Wiper Blade Replacement . . . . . . . 325
Windshield Replacement . . . . . . . . 326
Gas Strut(s) . . . . . . . . . . . . . . . . . . . . . . . 326
Headlamp Aiming
Front Headlamp Aiming . . . . . . . . . 327
Bulb Replacement
LED Lighting . . . . . . . . . . . . . . . . . . . . . 327
Electrical System
Electrical System Overload . . . . . . 327
Fuses and Circuit Breakers . . . . . . 328
Engine Compartment Fuse
Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 329
Instrument Panel Fuse Block . . . . 332
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . 335
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 337
All-Season Tires . . . . . . . . . . . . . . . . . . 337
Winter Tires . . . . . . . . . . . . . . . . . . . . . . 338
Summer Tires . . . . . . . . . . . . . . . . . . . . 338
Tire Sidewall Labeling . . . . . . . . . . . 339 Tire Designations . . . . . . . . . . . . . . . . . 340
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . . . . . 341
Tire Pressure . . . . . . . . . . . . . . . . . . . . . . 343
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . . . . . . 345
Tire Pressure Monitor System . . . 346
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . . . . . . 347
Tire Inspection . . . . . . . . . . . . . . . . . . . 350
Tire Rotation . . . . . . . . . . . . . . . . . . . . . 351
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 352
Buying New Tires . . . . . . . . . . . . . . . . 353
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . . . . . 354
Uniform Tire Quality Grading . . . 354
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . . . . . . 356
Wheel Replacement . . . . . . . . . . . . . . 356
Tire Chains . . . . . . . . . . . . . . . . . . . . . . . 356
If a Tire Goes Flat . . . . . . . . . . . . . . . . 357
Tire Changing . . . . . . . . . . . . . . . . . . . . . 358
Compact Spare Tire . . . . . . . . . . . . . . 364
Jump Starting
Jump Starting - North America . . . . . . . . . . . . . . . . . . . . . . . . . 364

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
304 VEHICLE CARE
Towing the Vehicle
Towing the Vehicle . . . . . . . . . . . . . . . 367
Recreational Vehicle Towing . . . . 368
Appearance Care
Exterior Care . . . . . . . . . . . . . . . . . . . . . . 370
Interior Care . . . . . . . . . . . . . . . . . . . . . . 374
Floor Mats . . . . . . . . . . . . . . . . . . . . . . . . 377
General Information
For service and parts needs, visit your
dealer. You will receive genuine GM
parts and GM-trained and supported
service people.
Genuine GM parts have one of these
marks:
California Proposition
65 Warning
{Warning
Most motor vehicles, including this
one, as well as many of its service
parts and fluids, contain and/or
emit chemicals known to the State
of California to cause cancer and
birth defects or other reproductive
harm. Engine exhaust, many parts
and systems, many fluids, and
some component wear by-products
contain and/or emit these
chemicals. For more information go
to www.P65Warnings.ca.gov/
passenger-vehicle.
See Battery - North America 0323 and
Jump Starting - North America 0364
and the back cover.