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GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Vehicle Care 331
affected if all the tires are not
replaced at the same time.
If proper rotation and
maintenance have been done,
all four tires should wear out at
about the same time. SeeTire
Rotation 0328. However, if it is
necessary to replace only one
axle set of worn tires, place the
new tires on the rear axle.
Winter tires with the same speed
rating as the original equipment
tires may not be available for H,
V, W, Y and ZR speed rated
tires. Never exceed the winter
tires’ maximum speed capability
when using winter tires with a
lower speed rating.
{Warning
Tires could explode during
improper service. Attempting
to mount or dismount a tire
could cause injury or death.
(Continued)
Warning (Continued)
Only your dealer or authorized
tire service center should
mount or dismount the tires.
{Warning
Mixing tires of different sizes,
brands, or types may cause
loss of control of the vehicle,
resulting in a crash or other
vehicle damage. Use the
correct size, brand, and type
of tires on all wheels.
{Warning
Using bias-ply tires on the
vehicle may cause the wheel
rim flanges to develop cracks
after many miles of driving.
A tire and/or wheel could fail
(Continued)
Warning (Continued)
suddenly and cause a crash.
Use only radial-ply tires with
the wheels on the vehicle.
If the vehicle tires must be
replaced with a tire that does not
have a TPC Spec number, make
sure they are the same size,
load range, speed rating, and
construction (radial) as the
original tires.
Vehicles that have a tire
pressure monitoring system
could give an inaccurate
low-pressure warning if non-TPC
Spec rated tires are installed.
See Tire Pressure Monitor
System 0323.
The Tire and Loading
Information label indicates the
original equipment tires on the
vehicle. See Vehicle Load Limits
0 217.
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GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
Vehicle Care 335
Warning (Continued)
cause loss of control and a crash.
Use another type of traction
device only if its manufacturer
recommends it for the vehicle's
tire size combination and road
conditions. Follow that
manufacturer's instructions. To
avoid vehicle damage, drive slow
and readjust or remove the
traction device if it contacts the
vehicle. Do not spin the wheels. If
traction devices are used, install
them on the front tires.
Caution
If the vehicle is equipped with
235/65R18 size tires, use tire
chains only where legal and only
when necessary. Use low profile
chains that add no more than
12 mm thickness to the tire tread
and inner sidewall. Use chains(Continued)
Caution (Continued)
that are the proper size for the
tires. Install them on the tires of
the front axle. Do not use chains
on the tires of the rear axle.
Tighten them as tightly as
possible with the ends securely
fastened. Drive slowly and follow
the chain manufacturer's
instructions. If the chains contact
the vehicle, stop and retighten
them. If the contact continues,
slow down until it stops. Driving
too fast or spinning the wheels
with chains on will damage the
vehicle.
If a Tire Goes Flat
It is unusual for a tire to blow out
while driving, especially if the tires
are maintained properly. See Tires
0 314. If air goes out of a tire, it is
much more likely to leak out slowly.
But if there is ever a blowout, here
are a few tips about what to expect
and what to do: If a front tire fails, the flat tire
creates a drag that pulls the vehicle
toward that side. Take your foot off
the accelerator pedal and grip the
steering wheel firmly. Steer to
maintain lane position, and then
gently brake to a stop, well off the
road, if possible.
A rear blowout, particularly on a
curve, acts much like a skid and
may require the same correction as
used in a skid. Stop pressing the
accelerator pedal and steer to
straighten the vehicle. It may be
very bumpy and noisy. Gently brake
to a stop, well off the road,
if possible.
{Warning
Driving on a flat tire will cause
permanent damage to the tire.
Re-inflating a tire after it has been
driven on while severely
underinflated or flat may cause a
blowout and a serious crash.
Never attempt to re-inflate a tire
(Continued)
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GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
354 Vehicle Care
Towing the Vehicle
Caution
Incorrectly towing a disabled
vehicle may cause damage. The
damage would not be covered by
the vehicle warranty.
Do not lash or hook to
suspension components. Use the
proper straps around the tires to
secure the vehicle.
Use only a flatbed tow truck for
towing a disabled vehicle. Never
use a sling type lift or damage will
occur. Use ramps to help reduce
approach angles if necessary.
A towed vehicle should have its
drive wheels off the ground.
Consult a professional towing
service if the disabled vehicle must
be towed.
Front Attachment Points
The vehicle is equipped with
specific attachment points to be
used by the towing provider. These
holes may be used to pull the
vehicle from a flat road surface onto
the flatbed tow truck.
Recreational Vehicle
Towing
Recreational vehicle towing means
towing the vehicle behind another
vehicle, such as behind a motor
home. The two most common types
of recreational vehicle towing are known as dinghy towing and dolly
towing. Dinghy towing is towing the
vehicle with all four wheels on the
ground. Dolly towing is towing the
vehicle with two wheels on the
ground and two wheels up on a
device known as a dolly.
Here are some important things to
consider before recreational vehicle
towing:
.
The towing capacity of the
towing vehicle. Be sure to read
the tow vehicle manufacturer's
recommendations.
. How far the vehicle will be
towed. Some vehicles have
restrictions on how far and how
long they can tow.
. The proper towing equipment.
See your dealer or trailering
professional for additional advice
and equipment
recommendations.
. If the vehicle is ready to be
towed. Just as preparing the
vehicle for a long trip, make sure
the vehicle is prepared to be
towed.
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GMC Acadia/Acadia Denali Owner Manual (GMNA-Localizing-U.S./Canada/
Mexico-11349114) - 2018 - crc - 9/21/17
OnStar 403
3. Say the entire number withoutpausing, including a “1”and the
area code. System responds:
“OK, calling.”
Calling 911 Emergency
1. Press=. System responds:
“OnStar ready.”
2. Say “Call.”System responds:
“Call. Please say the name or
number to call.”
3. Say “911”without pausing.
System responds: “911.”
4. Say “Call.”System responds:
“OK, dialing 911.”
Retrieve My Number
1. Press=. System responds:
“OnStar ready.”
2. Say “My number.” System
responds: “Your OnStar
Hands-Free Calling number is,”
then says the number.
End a Call
Press=. System responds: “Call
ended.”
Verify Minutes and Expiration
Press=and say “Minutes” then
“Verify” to check how many minutes
remain and their expiration date.
Diagnostics
By monitoring and reporting on the
vehicle’s key systems, OnStar
Advanced Diagnostics provides a
way to keep up on maintenance.
Capabilities vary by model. See
www.onstar.com for details and
system limitations. Message and
data rates may apply. Advanced
Diagnostics requires an active
OnStar paid service plan, e-mail
address on file, and enrollment in
Advanced Diagnostics.
Includes:
. Diagnostic Alerts: Set
preferences to receive real-time
e-mails, texts, or monthly reports
of the vehicle’s health. Or press
Qto have an Advisor initiate a
remote diagnostic report. .
Proactive Alerts: Receive a
real-time e-mail or text message
regarding potential issues with
key vehicle components, such
as the battery, fuel system,
or starter system. Alerts for
potential issues appear on the
infotainment display. Proactive
Alerts are designed to help
predict specific types of issues
based on information collected
from the vehicle. Other factors
may affect vehicle performance.
Not all issues will deliver alerts.
In some cases, a dealer service
check may be required to
confirm the accuracy of the
alerts.
. Dealer Maintenance Notification:
Have the vehicle notify your
preferred dealer when it is time
for maintenance. Your dealer will
then contact you to set up an
appointment.
To begin, pressQto speak to an
Advisor, or see www.onstar.com.