Cadillac XT5 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14590481) - 2021 - CRC - 10/22/20
276 DRIVING AND OPERATING
www.toptiergas.com for a list of TOP
TIER Detergent Gasoline marketers
and applicable countries.
Recommended Fuel (2.0L
L4 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.
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.
(Continued)
Cadillac XT5 Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
14590481) - 2021 - CRC - 10/22/20
DRIVING AND OPERATING 277
Caution (Continued)
.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 0276.
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 0105.
{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:
.Read and follow all the
instructions on the fuel pump
island.
.Turn off the engine when
refueling.
.Keep sparks, flames, and
smoking materials away
from fuel.
(Continued)
Warning (Continued)
.Do not leave the fuel pump
unattended.
.Avoid using electronic devices
while refueling.
.Do not re-enter the vehicle while
pumping fuel.
.Keep children away from the fuel
pump and never let children
pump fuel.
.Before touching the fill nozzle,
touch a metallic object to
discharge static electricity from
your body.
.Fuel can spray out if the fill
nozzle is inserted too quickly.
This spray can happen if the
tank is nearly full, and is more
likely in hot weather. Insert the
fill nozzle slowly and wait for any
hiss noise to stop before
beginning to flow fuel.
If equipped, the fuel door unlocks
when the vehicle doors are unlocked.
See Remote Keyless Entry (RKE) System
Operation 07.
