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GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/4/19
248 Driving and Operating
Fuel
Top Tier Fuel (Gasoline)
GM recommends the use of TOP
TIER Detergent Gasoline to keep
the engine clean, reduce engine
deposits, and maintain optimal
vehicle performance. Look for the
TOP TIER Logo or see
www.toptiergas.com for a list of TOP
TIER Detergent Gasoline marketers
and applicable countries.
Top Tier Fuel (Diesel)
GM recommends the use of TOP
TIER Diesel Fuel to keep the engine
clean, reduce engine deposits, and
maintain optimal vehicle
performance. Look for the TOP
TIER Logo or see
www.toptiergas.com for a list of TOP
TIER Diesel Fuel marketers and
applicable countries.
Recommended Fuel (LYX
- 1.5L L4 Turbo 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.
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GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/4/19
Driving and Operating 249
Recommended Fuel (LTG
- 2.0L L4 Turbo 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.
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.
. 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)
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, see Prohibited
Fuels (Gasoline) 0249.
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GMC Terrain/Terrain Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-13556230) - 2020 - CRC - 9/4/19
262 Driving and Operating
Trailer Towing
General Towing
Information
Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle to tow a trailer. Read the
entire section before towing a trailer.
To tow a disabled vehicle, see
Towing the Vehicle0352. To tow
the vehicle behind another vehicle
such as a motor home, see
Recreational Vehicle Towing 0353.
When towing with the 2.0L L4
engine, only use unleaded gasoline
with an octane rating of 89 or
higher. Using gasoline with a lower
octane rating while towing may
damage the engine and may not be
covered by the vehicle warranty.
Driving Characteristics
and Towing Tips
{Warning
You can lose control when towing
a trailer if the correct equipment is
not used or the vehicle is not
driven properly. For example,
if the trailer is too heavy or the
trailer brakes are inadequate for
the load, the vehicle may not stop
as expected. You and others
could be seriously injured. The
vehicle may also be damaged,
and the repairs would not be
covered by the vehicle warranty.
Pull a trailer only if all the steps in
this section have been followed.
Ask your dealer for advice and
information about towing a trailer
with the vehicle.
Driving with a Trailer
Trailering is different than just
driving the vehicle by itself.
Trailering means changes in handling, acceleration, braking,
durability, and fuel economy.
Successful, safe trailering takes
correct equipment, and it has to be
used properly.
The following information has many
time-tested, important trailering tips
and safety rules. Many of these are
important for your safety and that of
your passengers. Read this section
carefully before pulling a trailer.
When towing a trailer:
.
Become familiar with and follow
all state and local laws that
apply to trailer towing. These
requirements vary from state to
state.
. State laws may require the use
of extended side view mirrors.
Even if not required, you should
install extended side view
mirrors if your visibility is limited
or restricted while towing.
. Do not tow a trailer during the
first 800 km (500 mi) of vehicle
use to prevent damage to the
engine, axle, or other parts.