Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
268 DRIVING AND OPERATING
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.
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.(Continued)
Caution (Continued)
.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 (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, seeProhibited Fuels 0268.
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 0102.
{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)
Cadillac XT4 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14584367) - 2021 - CRC - 10/14/20
288 VEHICLE CARE
When selecting an oil of the
appropriate viscosity grade, it is
recommended to select an oil of the
correct specification. See
“Specification”earlier in this section.
Engine Oil Additives/Engine Oil
Flushes
Do not add anything to the oil. The
recommended oils meeting the dexos1
specification are all that is needed for
good performance and engine
protection.
Engine oil system flushes are not
recommended and could cause engine
damage not covered by the vehicle
warranty.
What to Do with Used Oil
Used engine oil contains certain
elements that can be unhealthy for
your skin and could even cause
cancer. Do not let used oil stay on
your skin for very long. Clean your
skin and nails with soap and water,
or a good hand cleaner. Wash or
properly dispose of clothing or rags
containing used engine oil. See the
manufacturer's warnings about the
use and disposal of oil products. Used oil can be a threat to the
environment. If you change your own
oil, be sure to drain all the oil from
the filter before disposal. Never
dispose of oil by putting it in the trash
or pouring it on the ground, into
sewers, or into streams or bodies of
water. Recycle it by taking it to a place
that collects used oil.
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system
that indicates when to change the
engine oil and filter. This is based on a
combination of factors which include
engine revolutions, engine
temperature, and miles driven. Based
on driving conditions, the mileage at
which an oil change is indicated can
vary considerably. For the oil life
system to work properly, the system
must be reset every time the oil is
changed.
When the system has calculated that
oil life has been diminished, it
indicates that an oil change is
necessary. A CHANGE ENGINE OIL
SOON message comes on. Change the
oil as soon as possible within the next
1 000 km (600 mi). It is possible that,
if driving under the best conditions,
the oil life system may indicate that
an oil change is not necessary for up
to a year. The engine oil and filter
must be changed at least once a year
and at this time the system must be
reset. Your dealer has trained service
people who will perform this work and
reset the system. It is also important
to check the oil regularly over the
course of an oil drain interval and
keep it at the proper level.
If the system is ever reset accidentally,
the oil must be changed at 5 000 km
(3,000 mi) since the last oil change.
Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil Life
System
Reset the system whenever the engine
oil is changed so that the system can
calculate the next engine oil change.
To reset the system:
1. Using the DIC controls on the right side of the steering wheel, display
REMAINING OIL LIFE on the DIC.
