Fuel - Cadillac XTS 2018 Owner's Manual

220 DRIVING AND OPERATING

Fuel

GM recommends the use of TOP TIER
Detergent Gasoline to keep the engine
cleaner and reduce engine deposits.
See www.toptiergas.com for a list of
TOP TIER Detergent Gasoline
marketers and applicable countries.
Do not use any fuel labeled E85 or
FlexFuel. Do not use gasoline with
ethanol levels greater than 15% by
volume.
For the LFX 3.6L V6 engine, use
regular unleaded gasoline meeting
ASTM specification D4814 with a
posted octane rating of 87 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.
For the LF3 3.6L Twin Turbo
V6 engine, use premium unleaded
gasoline meeting ASTM specification
D4814 with a posted octane rating of
93. If unavailable, unleaded gasoline
with a posted octane rating of 91 may
be used, but with reduced
performance and fuel economy. If the
octane is less than 91, the engine
could be damaged and the repairs
would not be covered by the vehicle
warranty. If heavy knocking is heard
when using gasoline rated at
93 octane, the engine needs service.
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 which 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, 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.