
Black plate (19,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-19
If the vehicle starts briefly but
then stops again, repeat these
steps. This clears the extra
gasoline from the engine.
Do not race the engine
immediately after starting it.
Operate the engine and
transmission gently until the oil
warms up and lubricates all
moving parts.
Notice: The engine is designed to
work with the electronics in the
vehicle. If you add electrical parts
or accessories, you could change
the way the engine operates.
Before adding electrical
equipment, check with your
dealer. If you do not, the engine
might not perform properly.
Any resulting damage would
not be covered by the vehicle
warranty.Engine Heater
The engine coolant heater can
provide easier starting and better
fuel economy during engine
warm-up in cold weather conditions
at or below 0°F (−18°C). Vehicles
with an engine coolant heater
should be plugged in at least four
hours before starting. Some models
may have an internal thermostat in
the cord which will prevent engine
coolant heater operation at
temperatures above 0°F (−18°C).
To Use the Engine Coolant
Heater
1. Turn off the engine.
2. Open the hood and unwrap the electrical cord. The cord is
located on the driver side of the
engine compartment. It is routed
around the windshield washer
fluid reservoir.
3. Plug the cord into a normal, grounded 110-volt AC outlet.
{WARNING
Plugging the cord into an
ungrounded outlet could cause an
electrical shock. Also, the wrong
kind of extension cord could
overheat and cause a fire. You
could be seriously injured. Plug
the cord into a properly grounded
three-prong 110-volt AC outlet.
If the cord will not reach, use a
heavy-duty three-prong extension
cord rated for at least 15 amps.
4. Before starting the engine, be sure to unplug and store the
cord as it was before to keep it
away from moving engine parts.
If you do not, it could be
damaged.
The length of time the heater should
remain plugged in depends on
several factors. Ask a dealer in the
area where you will be parking the
vehicle for the best advice on this.

Black plate (25,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-25
Notice:Shifting out of P (Park)
or N (Neutral) with the engine
running at high speed may
damage the transmission. The
repairs would not be covered by
the vehicle warranty. Be sure the
engine is not running at high
speed when shifting the vehicle.
D (Drive): This position is for
normal driving. It provides the best
fuel economy. If you need more
power for passing, and you are:
.Going less than 56 km/h
(35 mph), push the accelerator
pedal about halfway down.
.Going about 56 km/h (35 mph) or
more, push the accelerator all
the way down.
Notice: If the vehicle seems to
accelerate slowly or not shift
gears when you go faster, and
you continue to drive the vehicle
that way, you could damage the transmission. Have the vehicle
serviced right away. You can
drive in L (Low) when you are
driving less than 56 km/h (35 mph)
and D (Drive) for higher speeds
until then.
If the vehicle is stopped on a hill,
with your foot off the brake pedal,
the vehicle may roll. This is normal
and is due to the torque converter
designed to improve fuel economy
and performance. Use the brake to
hold the vehicle on a hill. Do not use
the accelerator pedal.
L (Low):
This position gives you
access to gear ranges. This
provides more engine braking but
lower fuel economy than D (Drive).
You can use it on very steep hills,
or in deep snow or mud.
Manual Mode
Electronic Range Select
(ERS) Mode
ERS mode allows you to choose
the top-gear limit of the transmission
and the vehicle's speed while
driving downhill or towing a trailer.
The vehicle has an electronic
shift position indicator within the
instrument panel cluster. When
using the ERS mode a number will
display next to the L, indicating the
current gear that has been selected.
To use this feature:
1. Move the shift lever to L (Low).
2. Press the plus/minus button located on the shift lever, to
increase or decrease the gear
range available.

Black plate (40,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-40 Driving and Operating
Fuel
Use of the recommended fuel is
an important part of the proper
maintenance of this vehicle. To help
keep the engine clean and maintain
optimum vehicle performance, we
recommend the use of gasoline
advertised as TOP TIER Detergent
Gasoline.
Look for the TOP TIER label on the
fuel pump to ensure gasoline meets
enhanced detergency standards
developed by auto companies. A list
of marketers providing TOP TIER
Detergent Gasoline can be found at
www.toptiergas.com.
Recommended Fuel
Use regular unleaded gasoline with
a posted octane rating of 87 or
higher. If the octane rating is less
than 87, an audible knocking noise,
commonly referred to as spark
knock, might be heard when driving.
If this occurs, use a gasoline rated
at 87 octane or higher as soon as
possible. If heavy knocking is heard
when using gasoline rated at
87 octane or higher, the engine
needs service.
Gasoline Specifications
(U.S. and Canada Only)
At a minimum, gasoline should
meet ASTM specification
D 4814 in the United States or
CAN/CGSB‐3.5 or 3.511 in Canada.
Some gasolines contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT). We recommend
against the use of gasolines
containing MMT. SeeFuel Additives
on page 9‑41 for additional
information.
California Fuel
Requirements
If the vehicle is certified to meet
California Emissions Standards, it is
designed to operate on fuels that
meet California specifications.

Black plate (41,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-41
See the underhood emission control
label. If this fuel is not available in
states adopting California Emissions
Standards, the vehicle will operate
satisfactorily on fuels meeting
federal specifications, but emission
control system performance might
be affected. The malfunction
indicator lamp could turn on and the
vehicle might fail a smog‐check test.
SeeMalfunction Indicator Lamp on
page 5‑18. If this occurs, return to
your authorized dealer for diagnosis.
If it is determined that the condition
is caused by the type of fuel used,
repairs might not be covered by the
vehicle warranty.
Fuels in Foreign
Countries
Never use leaded gasoline or any
other fuel not recommended in the
previous text on fuel. Costly repairs
caused by use of improper fuel
would not be covered by the vehicle
warranty. To check the fuel availability, ask an
auto club, or contact a major oil
company that does business in the
country where you will be driving.
Fuel Additives
To provide cleaner air, all gasolines
in the United States are now
required to contain additives that
help prevent engine and fuel system
deposits from forming, allowing the
emission control system to work
properly. In most cases, nothing
should have to be added to the fuel.
However, some gasolines contain
only the minimum amount of
additive required to meet U.S.
Environmental Protection Agency
regulations. To help keep fuel
injectors and intake valves clean
and avoid problems due to dirty
injectors or valves, look for gasoline
that is advertised as TOP TIER
Detergent Gasoline. Look for the
TOP TIER label on the fuel pump to
ensure gasoline meets enhanced
detergency standards developedby the auto companies. A list of
marketers providing TOP TIER
Detergent Gasoline can be found at
www.toptiergas.com.
For customers who do not use
TOP TIER Detergent Gasoline
regularly, one bottle of GM Fuel
System Treatment PLUS, added to
the fuel tank at every engine oil
change, can help clean deposits
from fuel injectors and intake
valves. GM Fuel System Treatment
PLUS is the only gasoline additive
recommended by General Motors.
It is available at your dealer.
Gasolines containing oxygenates,
such as ethers and ethanol, and
reformulated gasolines might be
available in your area. We
recommend that you use these
gasolines, if they comply with the
specifications described earlier.
However, E85 (85% ethanol) and
other fuels containing more than
15% ethanol must not be used in
vehicles that were not designed for
those fuels.

Black plate (42,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-42 Driving and Operating
Notice:This vehicle was not
designed for fuel that contains
methanol. Do not use fuel
containing methanol. It can
corrode metal parts in the fuel
system and also damage plastic
and rubber parts. That damage
would not be covered under the
vehicle warranty.
Some gasolines that are
not reformulated for low
emissions can contain an
octane-enhancing additive called
methylcyclopentadienyl manganese
tricarbonyl (MMT); ask the attendant
where you buy gasoline whether the
fuel contains MMT. We recommend
against the use of such gasolines.
Fuels containing MMT can reduce
spark plug life and affect emission
control system performance.
The malfunction indicator lamp
might turn on. If this occurs, return
to your dealer for service.Filling the Tank
{WARNING
Fuel vapor burns violently and a
fuel fire can cause bad injuries.
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. Do not smoke near fuel
or when refueling the vehicle.
Do not use cellular phones.
Keep sparks, flames, and
smoking materials away from fuel.
Do not leave the fuel pump
unattended when refueling the
vehicle. This is against the law in
some places. Do not re-enter the
vehicle while pumping fuel. Keep
children away from the fuel pump;
never let children pump fuel. The tethered fuel cap is located
behind a hinged fuel door on the
driver side of the vehicle.
To open the fuel door, push the
rearward center edge in and release
and it will open.
To remove the fuel cap, turn it
slowly counterclockwise. The fuel
cap has a spring in it; if the cap is
released too soon, it will spring back
to the right.

Black plate (43,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-43
While refueling, hang the tethered
fuel cap from the hook on the
fuel door.
{WARNING
Fuel can spray out on you if
you open the fuel cap too
quickly. If you spill fuel and then
something ignites it, you could be
badly burned. This spray can
happen if the tank is nearly full,
and is more likely in hot weather.
Open the fuel cap slowly and
wait for any hiss noise to stop.
Then unscrew the cap all the way.Be careful not to spill fuel. Do not
top off or overfill the tank and wait a
few seconds after you have finished
pumping before removing the
nozzle. Clean fuel from painted
surfaces as soon as possible.
See
Exterior Care on page 10‑86.
When replacing the fuel cap,
turn it clockwise until it clicks.
Make sure the cap is fully installed.
The diagnostic system can
determine if the fuel cap has been
left off or improperly installed.
This would allow fuel to
evaporate into the atmosphere.
See Malfunction Indicator Lamp on
page 5‑18.
{WARNING
If a fire starts while you are
refueling, do not remove the
nozzle. Shut off the flow of fuel
by shutting off the pump or by
notifying the station attendant.
Leave the area immediately.
Notice: If a new fuel cap is
needed, be sure to get the right
type of cap from your dealer.
The wrong type of fuel cap might
not fit properly, might cause the
malfunction indicator lamp to
light, and could damage the fuel
tank and emissions system.
See Malfunction Indicator Lamp
on page 5‑18.

Black plate (44,1)GMC Acadia/Acadia Denali Owner Manual - 2012
9-44 Driving and Operating
Filling a Portable Fuel
Container
{WARNING
Never fill a portable fuel container
while it is in the vehicle. Static
electricity discharge from the
container can ignite the fuel
vapor. You can be badly burned
and the vehicle damaged if this
occurs. To help avoid injury to you
and others:
.Dispense fuel only into
approved containers.
.Do not fill a container while it
is inside a vehicle, in a
vehicle's trunk, pickup bed,
or on any surface other than
the ground.(Continued)
WARNING (Continued)
.Bring the fill nozzle in contact
with the inside of the fill
opening before operating the
nozzle. Contact should be
maintained until the filling is
complete.
.Do not smoke while
pumping fuel.
.Do not use a cellular phone
while pumping fuel.
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 for towing a trailer.
See the following trailer towing
information in this section:
.For information on driving
while towing a trailer, see
“Driving Characteristics and
Towing Tips.”
.For maximum vehicle and trailer
weights, see“Trailer Towing.”
.For information on equipment
to tow a trailer, see “Towing
Equipment.”

Black plate (45,1)GMC Acadia/Acadia Denali Owner Manual - 2012
Driving and Operating 9-45
For information on towing a disabled
vehicle, seeTowing the Vehicle on
page 10‑82. For information on
towing the vehicle behind another
vehicle such as a motor home, see
Recreational Vehicle Towing on
page 10‑82.
Driving Characteristics
and Towing Tips
{WARNING
The driver can lose control when
pulling a trailer if the correct
equipment is not used or the
vehicle is not driven properly.
(Continued)
WARNING (Continued)
For example, if the trailer is too
heavy, the brakes may not work
well—or even at all. The driver
and passengers could be
seriously injured. The vehicle may
also be damaged; the resulting
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.
The vehicle can tow a trailer
when equipped with the proper
trailer towing equipment. For trailering capacity, see
Trailer
Towing on page 9‑49. Trailering
changes handling, acceleration,
braking, durability and fuel
economy. With the added weight,
the engine, transmission, wheel
assemblies and tires are forced to
work harder and under greater
loads. The trailer also adds wind
resistance, increasing the pulling
requirements. For safe trailering,
correctly use the proper trailering
equipment.
The following information has
important trailering tips and rules
for your safety and that of your
passengers. Read this section
carefully before pulling a trailer.