2021 CADILLAC XT6 check engine

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
372 VEHICLE CARE
.Use a nonabrasive wax on the
vehicle after washing to protect and
extend the molding finish.
Cleaning Exterior Lamps/Lenses,
Emblems, Decals, and Stripes
Use only lukewarm or cold water, a
soft cloth, and a car washing soap to
clean exterior lamps, lenses, emblems,
decals, and stripes. Follow instructions
under "Washing the Vehicle"
previously in this section.
Lamp covers are made of plastic, and
some have a UV protective coating. Do
not clean or wipe them when dry.
Do not use any of the following on
lamp covers:
.Abrasive or caustic agents.
.Washer fluids and other cleaning
agents in higher concentrations
than suggested by the manufacturer.
.Solvents, alcohols, fuels, or other
harsh cleaners.
.Ice scrapers or other hard items.
.Aftermarket appearance caps or
covers while the lamps are
illuminated, due to excessive heat
generated.
Caution
Failure to clean lamps properly can
cause damage to the lamp cover
that would not be covered by the
vehicle warranty.
Caution
Using wax on low gloss black finish
stripes can increase the gloss level
and create a non-uniform finish.
Clean low gloss stripes with soap
and water only.
Air Intakes
Clear debris from the air intakes,
between the hood and windshield,
when washing the vehicle.
Shutter System
The vehicle may have a shutter
system designed to help improve fuel
economy. Keep the shutter system
clear of debris, snow and ice. If the
check engine light is activated, please
check to see if the shutter system is
clear of debris, snow or ice.
Windshield and Wiper Blades
Clean the outside of the windshield
with glass cleaner.
Clean rubber blades using a lint-free
cloth or paper towel soaked with
windshield washer fluid or a mild
detergent. Wash the windshield

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
380 SERVICE AND MAINTENANCE
keep the vehicle in good working
condition, improves fuel economy, and
reduces vehicle emissions.
Because of the way people use
vehicles, maintenance needs vary.
There may need to be more frequent
checks and services. The Additional
Required Services - Normal are for
vehicles that:
.Carry passengers and cargo within
recommended limits on the Tire
and Loading Information label. See
Vehicle Load Limits0228.
.Are driven on reasonable road
surfaces within legal driving limits.
.Use the recommended fuel. See
Recommended Fuel (3.6L V6 Engine)
0286 or
Recommended Fuel (2.0L L4 Turbo
Engine) 0286.
Refer to the information in the
Maintenance Schedule Additional
Required Services - Normal chart. The Additional Required Services -
Severe are for vehicles that are:
.Mainly driven in heavy city traffic
in hot weather.
.Mainly driven in hilly or
mountainous terrain.
.Frequently towing a trailer.
.Used for high speed or competitive
driving.
.Used for taxi, police, or delivery
service.
Refer to the information in the
Maintenance Schedule Additional
Required Services - Severe chart.
{Warning
Performing maintenance work can
be dangerous and can cause serious
injury. Perform maintenance work
only if the required information,
proper tools, and equipment are
available. If they are not, see your
dealer to have a trained technician
do the work. See Doing Your Own
Service Work 0305.
Maintenance Schedule
Owner Checks and Services
Check the engine oil level. See Engine
Oil 0311.
Once a Month
.Check the tire inflation pressures.
See Tire Pressure 0343.
.Inspect the tires for wear. See Tire
Inspection 0350.
.Check the windshield washer fluid
level. See Washer Fluid 0321.
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

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
SERVICE AND MAINTENANCE 381
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 System0313.
Engine Air Filter Change
When the REPLACE AT NEXT OIL
CHANGE message displays, the engine
air filter should be replaced at the
next engine oil change. When the
REPLACE ENGINE AIR FILTER SOON
message displays, the engine air filter
should be replaced at the earliest
convenience. Reset the engine air
filter life system after the engine air
filter is replaced. See Engine Air Filter
Life System 0314.
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 Rotation0351.
.Check engine oil level and oil
life percentage. If needed, change
engine oil and filter, and reset oil
life system. See Engine Oil0311 and
Engine Oil Life System 0313.
.Check the air filter life percentage.
If necessary, replace the engine air
filter and reset the engine air filter
life system. See Engine Air Filter Life
System 0314.
.Check engine coolant level. See
Cooling System 0316.
.Check windshield washer fluid level.
See Washer Fluid 0321.
.Check tire inflation pressures. See
Tire Pressure 0343.
.Inspect tire wear. See Tire Inspection
0 350.
.Visually check for fluid leaks.
.Inspect brake system. See Exterior
Care 0370.
.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 0370.
.Inspect power steering for proper
electrical connections, binding,
cracks, chafing, etc.
.Visually inspect halfshafts and drive
shafts for excessive wear, lubricant
leaks, and/or damage including:
tube dents or cracks, constant
velocity joint or universal joint
looseness, cracked or missing boots,
loose or missing boot clamps, center
bearing excessive looseness, loose or
missing fasteners, and axle seal
leaks.
.Check restraint system components.
See Safety System Check 060.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
SERVICE AND MAINTENANCE 383
Maintenance Schedule
Additional Required Services -
Normal12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires and perform Required Services. Check
engine oil level and oil life percentage. Change
engine oil and filter, if needed.
Check engine air filter life percentage and status.
Change engine air filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (1)@ @@@@@
Inspect evaporative control system. (2)@ @@
Replace spark plugs. Inspect spark plug wires and/or
boots. 2.0L Engine.@ @
Replace spark plugs. Inspect spark plug wires and/or
boots. 3.6L Engine.@
Change rear axle fluid, if equipped with AWD. (3)@
Drain and fill engine cooling system. (4)@
Visually inspect accessory drive belts. (5)@
Replace brake fluid. (6)
Replace front and rear wiper blades. (7)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas struts. (8)@ @
Replace air conditioning desiccant. (9)

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
SERVICE AND MAINTENANCE 385
Maintenance Schedule
Additional Required Services -
Severe12 000 km/7,500 mi
24 000 km/15,000 mi
36 000 km/22,500 mi
48 000 km/30,000 mi
60 000 km/37,500 mi
72 000 km/45,000 mi
84 000 km/52,500 mi
96 000 km/60,000 mi
108 000 km/67,500 mi
120 000 km/75,000 mi
132 000 km/82,500 mi
144 000 km/90,000 mi
156 000 km/97,500 mi
168 000 km/105,000 mi
180 000 km/112,500 mi
192 000 km/120,000 mi
204 000 km/127,500 mi
216 000 km/135,000 mi
228 000 km/142,500 mi
240 000 km/150,000 mi
Rotate tires and perform Required Services. Check
engine oil level and oil life percentage. Change
engine oil and filter, if needed.
Check engine air filter life percentage and status.
Change engine air filter, if needed.
@ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @ @
Replace passenger compartment air filter. (1)@ @@@@@
Inspect evaporative control system. (2)@ @@
Change automatic transmission fluid.@@@
Replace spark plugs. Inspect spark plug wires and/or
boots. 2.0L Engine.@ @
Replace spark plugs. Inspect spark plug wires and/or
boots. 3.6L Engine.@
Change rear axle fluid, if equipped with AWD. (3)@ @
Drain and fill engine cooling system. (4)@
Visually inspect accessory drive belts. (5)@
Replace brake fluid. (6)
Replace front and rear wiper blades. (7)
@ @ @ @ @ @ @ @ @ @
Replace hood and/or body lift support gas struts. (8)@@
Replace air conditioning desiccant. (9)

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
386 SERVICE AND MAINTENANCE
Footnotes—Maintenance Schedule
Additional Required Services -
Severe
(1) 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.
(2) Visually check all fuel and vapor
lines and hoses for proper attachment,
connection, routing, and condition.
(3) 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.
(4) Or every five years, whichever
comes first. See Cooling System0316. (5)
Or every 10 years, whichever
comes first. Inspect for fraying,
excessive cracking, or damage; replace,
if needed.
(6) Replace brake fluid every five
years. See Brake Fluid 0322.
(7) Or every 12 months, whichever
comes first. See Wiper Blade
Replacement 0325.
(8) Or every 10 years, whichever
comes first. See Gas Strut(s)0326.
(9) 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.
The following list is intended to
explain the services and conditions to
look for that may indicate services are
required.
Battery
The 12-volt battery supplies power to
start the engine and operate any
additional electrical accessories.
.To avoid break-down or failure to
start the vehicle, maintain a battery
with full cranking power.

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
SERVICE AND MAINTENANCE 387
.Trained dealer technicians have the
diagnostic equipment to test the
battery and ensure that the
connections and cables are
corrosion-free.
Belts
.Belts may need replacing if they
squeak or show signs of cracking or
splitting.
.Trained dealer technicians have
access to tools and equipment to
inspect the belts and recommend
adjustment or replacement when
necessary.
Brakes
Brakes stop the vehicle and are crucial
to safe driving.
.Signs of brake wear may include
chirping, grinding, or squealing
noises, or difficulty stopping.
.Trained dealer technicians have
access to tools and equipment to
inspect the brakes and recommend
quality parts engineered for the
vehicle. Fluids
Proper fluid levels and approved fluids
protect the vehicle’s systems and
components. See
Recommended Fluids
and Lubricants 0389 for GM approved
fluids.
.Engine oil and windshield washer
fluid levels should be checked at
every fuel fill.
.Instrument cluster lights may come
on to indicate that fluids may be
low and need to be filled.
Hoses
Hoses transport fluids and should be
regularly inspected to ensure that
there are no cracks or leaks. With a
multi-point inspection, your dealer
can inspect the hoses and advise if
replacement is needed.
Lamps
Properly working headlamps,
taillamps, and brake lamps are
important to see and be seen on
the road.
.Signs that the headlamps need
attention include dimming, failure
to light, cracking, or damage. The brake lamps need to be checked
periodically to ensure that they light
when braking.
.With a multi-point inspection, your
dealer can check the lamps and
note any concerns.
Shocks and Struts
Shocks and struts help aid in control
for a smoother ride.
.Signs of wear may include steering
wheel vibration, bounce/sway while
braking, longer stopping distance,
or uneven tire wear.
.As part of the multi-point
inspection, trained dealer
technicians can visually inspect the
shocks and struts for signs of
leaking, blown seals, or damage, and
can advise when service is needed.
Tires
Tires need to be properly inflated,
rotated, and balanced. Maintaining
the tires can save money and fuel, and
can reduce the risk of tire failure.
.Signs that the tires need to be
replaced include three or more
visible treadwear indicators; cord or
fabric showing through the rubber;

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-14574701) -
2021 - CRC - 2/8/21
TECHNICAL DATA 395
ApplicationCapacities
Metric English
I3.6L V6 Engine 5.7 L
6.0 qt
Fuel Tank IFront-Wheel Drive 73.4 L
19.4 gal
IAll-Wheel Drive 82.1 L
21.7 gal
Wheel Nut Torque 190Y 140 lb ft
All capacities are approximate. When adding, be sure to fill to the approximate level, as recommended in this manual.
Recheck fluid level after filling.
*Engine cooling system capacity values are based on the entire cooling system and its components.
Engine Specifications
Engine VIN CodeTransmission Spark Plug Gap
2.0L L4 Engine (LSY) 4Automatic0.65–0.75 mm (0.026–0.030 in)
3.6L V6 Engine (LGX) SAutomatic0.80–0.90 mm (0.031–0.035 in)
Spark plug gaps are preset by the manufacturer. Re-gapping the spark plug is not recommended and can damage the
spark plug.