Page 345 of 507

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
344 Driving and Operating
Prohibited Fuels
Caution
Do not use fuels with any of
the following conditions;
doing so may damage the
vehicle and void its
warranty:
.For vehicles that are not
FlexFuel, fuel labeled
greater than 15% ethanol
by volume, such as
mid-level ethanol blends
(16–50% ethanol), E85,
or FlexFuel.
.Fuel with any amount of
methanol, methylal,
ferrocene, and aniline.
These fuels can corrode
metal fuel system parts or
damage plastic and rubber
parts.
.Fuel containing metals
such as
methylcyclopentadienyl
manganese tricarbonyl(Continued)
Caution (Continued)
(MMT), which can damage
the emissions control
system and spark plugs.
.Fuel with a posted octane
rating of less than the
recommended fuel. Using
this fuel will lower fuel
economy and
performance, and may
decrease the life of the
emissions catalyst.
Fuels in Foreign
Countries
The U.S., Canada, and Mexico
post fuel octane ratings in
anti-knock index (AKI). For fuel
not to use in a foreign country,
see Prohibited Fuels 0344.
Fuel Additives
TOP TIER Detergent Gasoline
is highly recommended for use
with your vehicle. If your
country does not have TOP
TIER Detergent Gasoline, add
ACDelco Fuel System Treatment Plus−Gasoline to
the vehicle’s gasoline fuel tank
at every oil change or
15 000 km (9,000 mi),
whichever occurs first. TOP
TIER Detergent Gasoline and
ACDelco Fuel System
Treatment Plus−Gasoline will
help keep your vehicle’s
engine fuel deposit free and
performing optimally.
Filling the Tank
An arrow on the fuel gauge
indicates which side of the
vehicle the fuel door is on. See
Fuel Gauge
0130.
{Warning
Fuel vapors and fuel fires
burn violently and can cause
injury or death.
Follow these guidelines to
help avoid injuries to you
and others:
(Continued)
Page 456 of 507

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
Service and Maintenance 455
may also be needed if you
notice reduced airflow,
windows fogging up,
or odors. Your local GM
Service location can help you
determine when it is the
right time to replace your
filter.
Every 96 000 km (60,000 mi)
.Replace spark plugs. Inspect
spark plug wires and/or
boots. (2.0L Engine)
Every 156 000 km
(97,500 mi)
.Replace spark plugs. Inspect
spark plug wires and/or
boots. (3.6L Engine)
Every 161 000 km
(100,000 mi)
.Replace hood and/or body
lift support gas struts. Or
every 10 years, whichever
comes first. See Gas Strut(s)
0 388. Every 240 000 km
(150,000 mi)
.Change rear 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.
.Drain and fill engine cooling
system. Or every six years,
whichever comes first. See
Cooling System
0376.
Severe Conditions
Requiring More Frequent
Maintenance*
.Public service, military,
or commercial use vehicles
to include the following:
‐ Ambulances, police cars,
and emergency rescue
vehicles. ‐
Civilian vehicles such as
light duty pick-up trucks,
SUVs, and passenger cars
that are used in military
applications.
‐ Recovery vehicles such as
tow trucks and flatbed
single vehicle carriers or
any vehicle that is
consistently used in towing
trailers or other loads.
‐ High use commercial
vehicles such as courier
delivery vehicles, private
security patrol vehicles,
or any vehicles that
operate on a 24–hour
basis.
‐ Any vehicle consistently
operated in a high sand or
dust environment such as
those used on oil pipelines
and similar applications..Vehicles that are regularly
used for short trips of 6 km
(4 mi) or less.
The oil life indicator will show
you when to change the oil
and filter. Under severe
Page 457 of 507

Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
456 Service and Maintenance
conditions the indicator may
come on before 12 000 km
(7,500 mi).
* Footnote: Under extreme
driving conditions listed
above, it may be necessary
to replace your spark plugs
at more frequent intervals.
For further assistance in
determining the most
suitable service maintenance
intervals for your vehicle,
please contact your
authorized GM Dealer.
Extreme service is for
vehicles mainly driven
off-road in four-wheel drive
or used in farming, mining,
forestry, or snow plowing.
Additional Required
Services—Severe Service
Every 72 000 km (45,000 mi)
.Change automatic
transmission fluid. Every 75 000 km
(120,000 mi)
.Change rear 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.
Owner Checks and
Services
Every Five Years
.Replace brake fluid every
five years. See Brake Fluid
0
384.
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.
Page 461 of 507
Cadillac XT6 Owner Manual (GMNA-Localizing-U.S./Canada-16405819) -
2023 - CRC - 3/22/22
460 Service and Maintenance
PartGM Part NumberACDelco
Part Number
Spark Plugs
I2.0L L4 Engine 55504354
41-130-IP
I3.6L V6 Engine 12646780
41-130
Wiper Blades IDriver Side –60 cm (23.6 in) 23372088
—
IPassenger Side –50 cm (19.7 in) 23360287
—
IRear –30 cm (11.8 in) 84215609
—