GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Driving and Operating 261
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.
Prohibited Fuels
(Gasoline)
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, see Prohibited
Fuels (Gasoline) 0261.
Fuel Additives (Gasoline)
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.
GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
262 Driving and Operating
Fuel Additives (Diesel)
TOP TIER Detergent Diesel is
highly recommended for use with
your vehicle. If your area does not
have TOP TIER Detergent Diesel,
GM recommends the use of
ACDelco Diesel Fuel Conditioner.
This will help maintain optimal
engine performance. GM does not
recommend other aftermarket diesel
additives.
If low-quality diesel is used for
refueling, GM recommends adding
ACDelco Fuel System Treatment
Plus-Diesel to help clean engine
deposits. This is available only at
your GM dealer.
Fuel for Diesel Engines
The selection of a high-quality fuel
is important for maintaining optimum
vehicle performance. Diesel fuel
should meet or exceed the minimum
requirements in the most current
versions of the local fuel standards
Do not use fuel with more than 15
ppm sulfur.Do not use a diesel blend containing
more than 20% biodiesel by volume.
Caution
Use of fuel that does not comply
with the required technical
standards can lead to engine
power loss, increased wear,
or engine damage and may void
your warranty.
Some improper fuels are:
. Diesel fuel with the addition
of gasoline.
. Diesel fuel mixed with
engine oil or automatic
transmission fluid.
. Triglyceride fuels, such as
raw vegetable oil or animal
fat, in any form, including
with blends of diesel or
biodiesel.
. Marine diesel fuel and
fuel oils.
(Continued)
Caution (Continued)
.Diesel-water emulsions,
such as Aquazole.
. Aftermarket diesel fuel
additives, which contain
alcohols, organo-metallic
additives, or water
emulsifiers.
Caution
If the vehicle is accidentally
refueled with gasoline, do not
continue driving the vehicle.
Driving the vehicle will damage
the fuel system. Have the vehicle
towed to a qualified technician to
have the gasoline removed from
the tank and fuel system. Refuel
with Ultra Low Sulfur Diesel fuel.
It is also recommended to have
the fuel system flushed with Ultra
Low Sulfur Diesel, to ensure all
gasoline is removed.
GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-12146071) - 2019 - crc - 7/27/18
Vehicle Care 297
Caution
Use only engine oil that is
approved to the dexos2
specification or equivalent engine
oil as defined in the preceding
paragraph. Failure to use the
recommended engine oil can
result in engine damage not
covered by the vehicle warranty.
Viscosity Grade
Use SAE 5W-30 viscosity grade
engine oil.
Cold Temperature Operation: In an
area of extreme cold, where the
temperature falls below −29 °C
(−20 °F), an SAE 0W-40 oil may be
used. An oil of this viscosity grade will provide easier cold starting for
the engine at extremely low
temperatures. 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
dexos 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
