GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Seats and Restraints 63
Servicing the Airbag-Equipped
Vehicle
Airbags affect how the vehicle should be
serviced. There are parts of the airbag
system in several places around the vehicle.
Your dealer and the service manual have
information about servicing the vehicle and
the airbag system. To purchase a service
manual, seePublication Ordering
Information 0371.
{Warning
For up to 10 seconds after the vehicle is
turned off and the battery is
disconnected, an airbag can still inflate
during improper service. You can be
injured if you are close to an airbag
when it inflates. Avoid yellow connectors.
They are probably part of the airbag
system. Be sure to follow proper service
procedures, and make sure the person
performing work for you is qualified to
do so.
Adding Equipment to the
Airbag-Equipped Vehicle
Adding accessories that change the vehicle's
frame, bumper system, height, front end,
or side sheet metal may keep the airbag
system from working properly.
The operation of the airbag system can also
be affected by changing, including
improperly repairing or replacing, any parts
of the following:
.Airbag system, including airbag modules,
front or side impact sensors, sensing and
diagnostic module, airbag wiring, or front
center console
.Front seats, including stitching, seams or
zippers
.Seat belts
.Steering wheel, instrument panel,
overhead console, ceiling trim, or pillar
garnish trim
.Inner door seals, including speakers
Your dealer and the service manual have
information about the location of the airbag
modules and sensors, sensing and diagnostic
module, and airbag wiring along with the
proper replacement procedures. In addition, the vehicle has a passenger
sensing system for the front outboard
passenger position, which includes sensors
that are part of the passenger's seat. The
passenger sensing system may not operate
properly if the original seat trim is replaced
with non-GM covers, upholstery, or trim,
or with GM covers, upholstery, or trim
designed for a different vehicle. Any object,
such as an aftermarket seat heater or a
comfort enhancing pad or device, installed
under or on top of the seat fabric, could
also interfere with the operation of the
passenger sensing system. This could either
prevent proper deployment of the passenger
airbag(s) or prevent the passenger sensing
system from properly turning off the
passenger airbag(s). See
Passenger Sensing
System 059.
If the vehicle has rollover roof-rail airbags,
see Different Size Tires and Wheels 0316 for
additional important information.
If the vehicle must be modified because you
have a disability and you have questions
about whether the modifications will affect
the vehicle's airbag system, or if you have
questions about whether the airbag system
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Instruments and Controls 113
If this happens, pull over and turn off the
engine as soon as possible. SeeEngine
Overheating 0285.
Tire Pressure Light
For vehicles with the Tire Pressure Monitor
System (TPMS), this light comes on briefly
when the engine is started. It provides
information about tire pressures and
the TPMS.
When the Light Is On Steady
This indicates that one or more of the tires
are significantly underinflated.
A Driver Information Center (DIC) tire
pressure message may also display. Stop as
soon as possible, and inflate the tires to the
pressure value shown on the Tire and
Loading Information label. See Tire Pressure
0 307. When the Light Flashes First and Then Is On
Steady
If the light flashes for about a minute and
then stays on, there may be a problem with
the TPMS. If the problem is not corrected,
the light will come on at every ignition
cycle. See
Tire Pressure Monitor Operation
0 310.
Engine Oil Pressure Light
Oil pressure can vary with engine speed,
outside temperature, and oil viscosity.
On some models, the oil pump will vary
engine oil pressure according to engine
needs. Oil pressure may change quickly as
the engine speed or load varies. This is
normal. If the oil pressure warning light or
Driver Information Center (DIC) message
indicates oil pressure outside the normal
operating range, check the vehicle's oil as
soon as possible.
Caution
Lack of proper engine oil maintenance
can damage the engine. Driving with the
engine oil low can also damage the
engine. The repairs would not be covered
(Continued)
Caution (Continued)
by the vehicle warranty. Check the oil
level as soon as possible. Add oil if
required, but if the oil level is within the
operating range and the oil pressure is
still low, have the vehicle serviced.
Always follow the maintenance schedule
for changing engine oil.
This light should come on briefly as the
engine is started. If it does not come on,
have the vehicle serviced by your dealer.
If the light comes on and stays on, it means
that oil is not flowing through the engine
properly. The vehicle could be low on oil
and might have some other system
problem. See your dealer.
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
200 Driving and Operating
Fuel
Top Tier Fuel . . . . . . . . . . . . . . . . . . . . . . . . . . 253
Recommended Fuel . . . . . . . . . . . . . . . . . . . . 253
Prohibited Fuels . . . . . . . . . . . . . . . . . . . . . . . 254
Fuels in Foreign Countries . . . . . . . . . . . . . 254
Fuel Additives . . . . . . . . . . . . . . . . . . . . . . . . . 254
Filling the Tank . . . . . . . . . . . . . . . . . . . . . . . . 254
Filling a Portable Fuel Container . . . . . . . 256
Trailer Towing
General Towing Information . . . . . . . . . . . 256
Driving Characteristics andTowing Tips . . . . . . . . . . . . . . . . . . . . . . . . . 256
Trailer Towing . . . . . . . . . . . . . . . . . . . . . . . . . 259
Towing Equipment . . . . . . . . . . . . . . . . . . . . 262
Trailer Sway Control (TSC) . . . . . . . . . . . . . 265
Conversions and Add-Ons
Add-On Electrical Equipment . . . . . . . . . . 266
Driving Information
Driving for Better Fuel Economy
Driving habits can affect fuel mileage. Here
are some driving tips to get the best fuel
economy possible.
.Set the climate controls to the desired
temperature after the engine is started,
or turn them off when not required.
.On AWD vehicles, see Driver Mode Control
0 228.
.Avoid fast starts and accelerate smoothly.
.Brake gradually and avoid abrupt stops.
.Avoid idling the engine for long periods
of time.
.When road and weather conditions are
appropriate, use cruise control.
.Always follow posted speed limits or
drive more slowly when conditions
require.
.Keep vehicle tires properly inflated.
.Combine several trips into a single trip.
.Replace the vehicle's tires with the same
TPC Spec number molded into the tire's
sidewall near the size.
.Follow recommended scheduled
maintenance.
Distracted Driving
Distraction comes in many forms and can
take your focus from the task of driving.
Exercise good judgment and do not let other
activities divert your attention away from
the road. Many local governments have
enacted laws regarding driver distraction.
Become familiar with the local laws in
your area.
To avoid distracted driving, keep your eyes
on the road, keep your hands on the
steering wheel, and focus your attention on
driving.
.Do not use a phone in demanding driving
situations. Use a hands-free method to
place or receive necessary phone calls.
.Watch the road. Do not read, take notes,
or look up information on phones or
other electronic devices.
.Designate a front seat passenger to
handle potential distractions.
.Become familiar with vehicle features
before driving, such as programming
favorite radio stations and adjusting
climate control and seat settings. Program
all trip information into any navigation
device prior to driving.
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
204 Driving and Operating
{Warning
When driving off-road, bouncing and
quick changes in direction can easily
throw you out of position. This could
cause you to lose control and crash. You
and your passengers should always wear
seat belts.
Before Driving Off-Road
.Have all necessary maintenance and
service work completed.
.Fuel the vehicle, fill fluid levels, and check
inflation pressure in all tires, including the
spare, if equipped.
.Read all the information about AWD
vehicles in this manual.
.Make sure all underbody shields,
if equipped, are properly attached.
.Know the local laws that apply to off-road
driving.
To gain more ground clearance if needed, it
may be necessary to remove the front fascia
lower air dam. However, driving without the
air dam reduces fuel economy.
Caution
Operating the vehicle for extended
periods without the front fascia lower air
dam installed can cause improper airflow
to the engine. Reattach the front fascia
air dam after off-road driving.
Loading the Vehicle for Off-Road Driving
{Warning
.Unsecured cargo on the load floor can
be tossed about when driving over
rough terrain. You or your passengers
can be struck by flying objects. Secure
the cargo properly.
.Keep cargo in the cargo area as far
forward and as low as possible. The
heaviest things should be on the floor,
forward of the rear axle.
.Heavy loads on the roof raise the
vehicle's center of gravity, making it
more likely to roll over. You can be
seriously or fatally injured if the
vehicle rolls over. Put heavy loads
inside the cargo area, not on the roof.
For more information about loading the
vehicle, see Vehicle Load Limits 0209.
Environmental Concerns
.Always use established trails, roads, and
areas that have been set aside for public
off-road recreational driving and obey all
posted regulations.
.Do not damage shrubs, flowers, trees,
or grasses or disturb wildlife.
.Do not park over things that burn. See
Parking over Things That Burn 0219.
Driving on Hills
Driving safely on hills requires good
judgment and an understanding of what the
vehicle can and cannot do.
{Warning
Many hills are simply too steep for any
vehicle. Driving up hills can cause the
vehicle to stall. Driving down hills can
cause loss of control. Driving across hills
can cause a rollover. You could be injured
or killed. Do not drive on steep hills.
Before driving on a hill, assess the
steepness, traction, and obstructions. If the
terrain ahead cannot be seen, get out of the
vehicle and walk the hill before driving
further.
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 207
More frequent maintenance service is
required. SeeMaintenance Schedule 0346.
Driving on Wet Roads
Rain and wet roads can reduce vehicle
traction and affect your ability to stop and
accelerate. Always drive slower in these
types of driving conditions and avoid driving
through large puddles and deep-standing or
flowing water.
{Warning
Wet brakes can cause crashes. They
might not work as well in a quick stop
and could cause pulling to one side. You
could lose control of the vehicle.
After driving through a large puddle of
water or a car/vehicle wash, lightly apply
the brake pedal until the brakes work
normally.
Flowing or rushing water creates strong
forces. Driving through flowing water
could cause the vehicle to be carried
away. If this happens, you and other
vehicle occupants could drown. Do not
(Continued)
Warning (Continued)
ignore police warnings and be very
cautious about trying to drive through
flowing water.
Hydroplaning
Hydroplaning is dangerous. Water can build
up under the vehicle's tires so they actually
ride on the water. This can happen if the
road is wet enough and you are going fast
enough. When the vehicle is hydroplaning, it
has little or no contact with the road.
There is no hard and fast rule about
hydroplaning. The best advice is to slow
down when the road is wet.
Other Rainy Weather Tips
Besides slowing down, other wet weather
driving tips include:
.Allow extra following distance.
.Pass with caution.
.Keep windshield wiping equipment in
good shape.
.Keep the windshield washer fluid reservoir
filled.
.Have good tires with proper tread depth.
SeeTires 0300.
.Turn off cruise control.
.Activate All-Wheel Drive (AWD) mode. See
Driver Mode Control 0228.
Hill and Mountain Roads
Driving on steep hills or through mountains
is different than driving on flat or rolling
terrain. Tips include:
.Keep the vehicle serviced and in good
shape.
.Check all fluid levels, brakes, tires, cooling
system, and transmission.
.Shift to a lower gear when going down
steep or long hills.
{Warning
Using the brakes to slow the vehicle on a
long downhill slope can cause brake
overheating, can reduce brake
performance, and could result in a loss of
braking. Shift the transmission to a lower
gear to let the engine assist the brakes
on a steep downhill slope.
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
210 Driving and Operating
Warning (Continued)
systems to break and change the
way the vehicle handles. This could
cause loss of control and a crash.
Overloading can also reduce stopping
performance, damage the tires, and
shorten the life of the vehicle.
Tire and Loading Information Label
Example Label
A vehicle-specific Tire and Loading
Information label is attached to the
center pillar (B-pillar). The tire and
loading information label shows the number of occupant seating
positions (1), and the maximum vehicle
capacity weight (2) in kilograms and
pounds.
The Tire and Loading Information label
also shows the size of the original
equipment tires (3) and the
recommended cold tire inflation
pressures (4). For more information on
tires and inflation see
Tires0300 and
Tire Pressure 0307.
There is also important loading
information on the vehicle Certification/
Tire label. It may show the Gross
Vehicle Weight Rating (GVWR) and the
Gross Axle Weight Rating (GAWR) for
the front and rear axle. See
“Certification/Tire Label” later in this
section.
“Steps for Determining Correct Load Limit–
1.
Locate the statement "The combined
weight of occupants and cargo
should never exceed XXX kg or
XXX lbs." on your vehicle’s placard.
2.Determine the combined weight of
the driver and passengers that will
be riding in your vehicle.
3.Subtract the combined weight of the
driver and passengers from XXX kg
or XXX lbs.
4.The resulting figure equals the
available amount of cargo and
luggage load capacity. For example,
if the "XXX" amount equals 1400 lbs.
and there will be five 150 lb
passengers in your vehicle, the
amount of available cargo and
luggage load capacity is 650 lbs.
(1400-750 (5 x 150) = 650 lbs.)
5.Determine the combined weight of
luggage and cargo being loaded on
the vehicle. That weight may not
safely exceed the available cargo and
luggage load capacity calculated in
Step 4.
6.If your vehicle will be towing a
trailer, load from your trailer will be
transferred to your vehicle. Consult
this manual to determine how this
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
212 Driving and Operating
Certification/Tire Label
Label Example
A vehicle-specific Certification/Tire label
is attached to the center pillar (B-pillar).
The label may show the size of the
vehicle's original tires and the inflation
pressures needed to obtain the gross
weight capacity of the vehicle. The label
shows the gross weight capacity of the
vehicle. This is called the Gross Vehicle
Weight Rating (GVWR). The GVWR
includes the weight of the vehicle, all
occupants, fuel, and cargo.The Certification/Tire label may also
show the maximum weights for the
front and rear axles, called the Gross
Axle Weight Rating (GAWR). To find out
the actual loads on the front and rear
axles, weigh the vehicle at a weigh
station. Your dealer can help with this.
Be sure to spread the load equally on
both sides of the centerline.
Caution
Overloading the vehicle may cause
damage. Repairs would not be covered by
the vehicle warranty. Do not overload the
vehicle.
{Warning
Things inside the vehicle can strike
and injure people in a sudden stop or
turn, or in a crash.
.Put things in the cargo area of the
vehicle. In the cargo area, put
them as far forward as possible.
Try to spread the weight evenly.
(Continued)
Warning (Continued)
.Never stack heavier things, like
suitcases, inside the vehicle so
that some of them are above the
tops of the seats.
.Do not leave an unsecured child
restraint in the vehicle.
.Secure loose items in the vehicle.
.Do not leave a seat folded down
unless needed.
Starting and Operating
New Vehicle Break-In
Caution
The vehicle does not need an elaborate
break-in. But it will perform better in the
long run if you follow these guidelines:
.Do not drive at any one constant
speed, fast or slow, for the first
800 km (500 mi). Do not make
full-throttle starts. Avoid downshifting
to brake or slow the vehicle.
(Continued)
GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-14608671) - 2021 - CRC - 10/26/20
Driving and Operating 263
2. Push the bottom of the cover forwarduntil the lower tabs line up with the
lower slots (1).
3. Snap the hitch cover into place by pushing the upper corners forward.
4. Reinstall the two fasteners on the lower tabs (2).
Consider using mechanical sway controls
with any trailer. Ask a trailering professional
about sway controls or refer to the trailer
manufacturer's recommendations and
instructions.
Weight-Distributing Hitch Adjustment
1. Front of Vehicle
2. Body to Ground Distance
When using a weight-distributing hitch,
measure the front fender height distance (2)
before connecting the trailer. Adjust the
spring bars until the front fender height
distance (2) is the same height before the
trailer was connected. Do not reduce the
front fender height below the initial
distance (2).
Tires
.Do not tow a trailer while using a
compact spare tire on the vehicle.
.Tires must be properly inflated to support
loads while towing a trailer. See Tires
0 300 for instructions on proper tire
inflation.
Safety Chains
Always attach chains between the vehicle
and the trailer, and attach the chains to the
holes on the trailer hitch platform.
Instructions about safety chains may be
provided by the hitch manufacturer or by
the trailer manufacturer.
Cross the safety chains under the tongue of
the trailer to help prevent the tongue from
contacting the road if it becomes separated
from the hitch. Always leave just enough
slack so the combination can turn. Never
allow safety chains to drag on the ground.
Trailer Brakes
Loaded trailers over 450 kg (1,000 lb) must
be equipped with brake systems and with
brakes for each axle. Trailer braking
equipment conforming to Canadian
Standards Association (CSA) requirement
CAN3-D313, or its equivalent, is
recommended.
State or local regulations may require
trailers to have their own braking system if
the loaded weight of the trailer exceeds
certain minimums that can vary from state
to state. Read and follow the instructions for
the trailer brakes so they are installed,
adjusted, and maintained properly. Never
attempt to tap into your vehicle's hydraulic
brake system. If you do, both the vehicle
anti-lock brakes and the trailer brakes may
not function, which could result in a crash.
Trailer Wiring Harness
lf equipped, the trailer wiring harness, with
a 7-pin connector is mounted on the trailer
hitch.