wheel GMC ACADIA 2007 Service Manual

Highway Hypnosis
Is there actually such a condition as highway
hypnosis? Or is it just plain falling asleep at
the wheel? Call it highway hypnosis, lack of
awareness, or whatever.
There is something about an easy stretch of road
with the same scenery, along with the hum of
the tires on the road, the drone of the engine,
and the rush of the wind against the vehicle that
can make you sleepy. Do not let it happen to you!
If it does, your vehicle can leave the road in
less than a second, and you could crash and
be injured.
What can you do about highway hypnosis?
First, be aware that it can happen.Then here are some tips:Make sure your vehicle is well ventilated,
with a comfortably cool interior.
Keep your eyes moving. Scan the road ahead
and to the sides. Check your vehicle’s mirrors
and instruments frequently.
If you get sleepy, pull off the road into a rest,
service, or parking area and take a nap, get
some exercise, or both. For safety, treat
drowsiness on the highway as an emergency.
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You will need a well-charged battery to restart the
vehicle, and possibly for signaling later on with
the headlamps. Let the heater run for a while.
Then, shut the engine off and close the window
almost all the way to preserve the heat. Start
the engine again and repeat this only when you
feel really uncomfortable from the cold. But do it as
little as possible. Preserve the fuel as long as
you can. To help keep warm, you can get out of
the vehicle and do some fairly vigorous exercises
every half hour or so until help comes.
If Your Vehicle is Stuck in Sand,
Mud, Ice, or Snow
In order to free your vehicle when it is stuck, you
need to spin the wheels, but you do not want
to spin the wheels too fast. The method known
as rocking can help you get out when you
are stuck, but you must use caution.
{CAUTION:
If you let your vehicle’s tires spin at high
speed, they can explode, and you or others
could be injured. And, the transmission or
other parts of the vehicle can overheat.
That could cause an engine compartment
re or other damage. When you are stuck,
spin the wheels as little as possible. Do not
spin the wheels above 35 mph (55 km/h) as
shown on the speedometer.
Notice:Spinning the wheels can destroy parts
of your vehicle as well as the tires. If you
spin the wheels too fast while shifting
the transmission back and forth, you can
destroy the transmission.
For information about using tire chains on your
vehicle, seeTire Chains on page 456.
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Rocking Your Vehicle to Get It Out
First, turn the steering wheel left and right to clear
the area around the front wheels. Turn the
traction control part of the StabiliTrak
®System off.
SeeStabiliTrak®System on page 337. Then
shift back and forth between REVERSE (R) and a
forward gear, spinning the wheels as little as
possible. To prevent transmission wear, wait until
the wheels stop spinning before shifting gears.
Release the accelerator pedal while you shift, and
press lightly on the accelerator pedal when the
transmission is in gear. By slowly spinning
the wheels in the forward and reverse directions,
you will cause a rocking motion that could free
your vehicle. If that does not get your vehicle out
after a few tries, it might need to be towed
out. If your vehicle does need to be towed out,
seeTowing Your Vehicle on page 367.
Loading Your Vehicle
It is very important to know how much weight your
vehicle can carry. This weight is called the
vehicle capacity weight and includes the weight of
all occupants, cargo, and all nonfactory-installed
options. Two labels on your vehicle show how
much weight it may properly carry, the Tire and
Loading Information label and the Certication/Tire
label.
{CAUTION:
Do not load your vehicle any heavier than
the Gross Vehicle Weight Rating (GVWR),
or either the maximum front or rear Gross
Axle Weight Rating (GAWR). If you do,
parts on your vehicle can break, and it
can change the way your vehicle handles.
These could cause you to lose control
and crash. Also, overloading can shorten
the life of your vehicle.
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Towing
Towing Your Vehicle
Consult your dealer/retailer or a professional
towing service if you need to have your disabled
vehicle towed. SeeRoadside Assistance Program
on page 524.
If you want to tow your vehicle behind another
vehicle for recreational purposes (such as behind
a motorhome), see “Recreational Vehicle
Towing” following.
Recreational Vehicle Towing
Recreational vehicle towing means towing your
vehicle behind another vehicle – such as behind a
motorhome. The two most common types of
recreational vehicle towing are known as “dinghy
towing” (towing your vehicle with all four wheels
on the ground) and “dolly towing” (towing
your vehicle with two wheels on the ground and
two wheels up on a device known as a “dolly”).With the proper preparation and equipment, many
vehicles can be towed in these ways. See “Dinghy
Towing” and “Dolly Towing” following in this
section.
Here are some important things to consider before
you do recreational vehicle towing:
What’s the towing capacity of the towing
vehicle? Be sure you read the tow vehicle
manufacturer’s recommendations.
How far will you tow? Some vehicles have
restrictions on how far and how long they
can tow.
Do you have the proper towing equipment?
See your dealer/retailer or trailering
professional for additional advice and
equipment recommendations.
Is your vehicle ready to be towed? Just as
you would prepare your vehicle for a long
trip, you’ll want to make sure your vehicle is
prepared to be towed. SeeBefore Leaving on
a Long Trip on page 352.
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Dinghy Towing
If you have a front-wheel-drive vehicle, it can be
dinghy towed from the front. These vehicles
may also be towed by putting the front wheels on
a dolly. See “Dolly Towing” later in this section.
If you have an all-wheel-drive vehicle, it can
be dinghy towed from the front. You can also tow
these vehicles by placing them on a platform
trailer with all four wheels off of the ground.
These vehicles cannot be towed using a dolly.
For vehicles being dinghy towed, the vehicle
should be run at the beginning of each day and
at each RV fuel stop for about ve minutes.
This will ensure proper lubrication of transmission
components. Put the IGN (Ignition) fuse in to
start the vehicle.To tow your vehicle from the front with all four
wheels on the ground:
1. Position the vehicle to tow and then secure it.
2. Turn the ignition to OFF.
3. Set the parking brake.
4. To prevent your battery from draining while
the vehicle is being towed, remove the IGN
(Ignition) fuse from the underhood fuse block.
SeeUnderhood Fuse Block on page 493.
5. Turn the ignition to ACCESSORY.
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6. Shift your transmission to NEUTRAL (N).
7. Release the parking brake.
Notice:If you tow your vehicle without
performing each of the steps listed under
“Dinghy Towing,” you could damage the
automatic transmission. Be sure to follow all
steps of the dinghy towing procedure prior
to and after towing your vehicle.
Notice:If you exceed 65 mph (105 km/h) while
towing your vehicle, it could be damaged.
Never exceed 65 mph (105 km/h) while towing
your vehicle.
Once you have reached your destination, do the
following:
1. Set the parking brake.
2. Turn the ignition key to OFF and remove the
key from the ignition.
3. Reinstall the IGN (Ignition) fuse.
Notice:Don’t tow a vehicle with the front
drive wheels on the ground if one of the front
tires is a compact spare tire. Towing with
two different tire sizes on the front of the
vehicle can cause severe damage to the
transmission.Dolly Towing (All-Wheel-Drive Vehicles)
All-wheel-drive vehicles must not be towed with
two wheels on the ground. To properly tow
these vehicles, they should be placed on a
platform trailer with all four wheels off of the
ground or dinghy towed from the front.
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Dolly Towing (Front-Wheel-Drive
Vehicles Only)
To tow your front-wheel-drive vehicle from the
front with two wheels on the ground:
1.
Put the front wheels on a dolly.
2.Move the shift lever to PARK (P).
3.Set the parking brake and then remove the key.
4.Clamp the steering wheel in a straight-ahead
position with a clamping device designed
for towing.
5. Release the parking brake.
Towing Your Vehicle From the Rear
Notice:Towing your vehicle from the rear
could damage it. Also, repairs would not
be covered by the warranty. Never have your
vehicle towed from the rear.
Do not tow your vehicle from the rear.
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Towing a Trailer
{CAUTION:
If you do not use the correct equipment
and drive properly, you can lose control
when you pull a trailer. For example, if the
trailer is too heavy, the brakes may not
work well — or even at all. You and your
passengers could be seriously injured.
You may also damage your vehicle; the
resulting repairs would not be covered by
your warranty. Pull a trailer only if you
have followed all the steps in this section.
Ask your dealer/retailer for advice and
information about towing a trailer with
your vehicle.
To identify the trailering capacity of your vehicle,
you should read the information in “Weight of
the Trailer” that appears later in this section.But trailering is different than just driving your
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.
That’s the reason for this part. In it are many
time-tested, important trailering tips and safety
rules. Many of these are important for your safety
and that of your passengers. So please read
this section carefully before you pull a trailer.
Load-pulling components such as the engine,
transmission, rear axle, wheel assemblies and tires
are forced to work harder against the drag of
the added weight. The engine is required
to operate at relatively higher speeds and under
greater loads, generating extra heat. What’s more,
the trailer adds considerably to wind resistance,
increasing the pulling requirements.
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Operating the vehicle in tow/haul when lightly
loaded or with no trailer at all will not cause
damage. However, there is no benet to the
selection of Tow/Haul when the vehicle is
unloaded. Such a selection when unloaded may
result in unpleasant engine and transmission
driving characteristics and reduced fuel economy.
Tow/Haul is recommended only when pulling a
heavy trailer or a large or heavy load.
Weight of the Trailer
How heavy can a trailer safely be?
It depends on how you plan to use your rig.
For example, speed, altitude, road grades, outside
temperature and how much your vehicle is used
to pull a trailer are all important. It can also depend
on any special equipment that you have on your
vehicle, and the amount of tongue weight the
vehicle can carry. See “Weight of the Trailer
Tongue” later in this section for more information.
Maximum trailer weight is calculated assuming
only the driver is in the tow vehicle and it
has all the required trailering equipment.The weight of additional optional equipment,
passengers and cargo in the tow vehicle must be
subtracted from the maximum trailer weight.
Look in the following chart to nd the maximum
trailer weight for your vehicle.
PackageMaximum
Trailer Weight*GCWR
Front-Wheel
Drive4,500 lbs
(2 041 kg)9,500 lbs
(4 309 kg)
All-Wheel Drive4,500 lbs
(2 041 kg)9,700 lbs
(4 400 kg)
*The Gross Combination Weight Rating (GCWR)
is the total allowable weight of the completely
loaded vehicle and trailer including any
passengers, cargo, equipment and conversions.
The GCWR for your vehicle should not be
exceeded.
Ask your dealer/retailer for our trailering
information or advice, or write us at our Customer
Assistance Offices. SeeCustomer Assistance
Offices on page 522for more information.
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Passing
You’ll need more passing distance up ahead when
you’re towing a trailer. And, because you’re a
good deal longer, you’ll need to go much farther
beyond the passed vehicle before you can
return to your lane.
Backing Up
Hold the bottom of the steering wheel with
one hand. Then, to move the trailer to the left,
just move that hand to the left. To move the trailer
to the right, move your hand to the right. Always
back up slowly and, if possible, have someone
guide you.
Making Turns
Notice:Making very sharp turns while
trailering could cause the trailer to come in
contact with the vehicle. Your vehicle could
be damaged. Avoid making very sharp turns
while trailering.When you’re turning with a trailer, make wider
turns than normal. Do this so your trailer
won’t strike soft shoulders, curbs, road signs,
trees or other objects. Avoid jerky or sudden
maneuvers. Signal well in advance.
Turn Signals When Towing a Trailer
When you tow a trailer, your vehicle may need a
different turn signal asher and/or extra wiring.
Check with your dealer/retailer. The arrows
on your instrument panel will ash whenever you
signal a turn or lane change. Properly hooked
up, the trailer lamps will also ash, telling other
drivers you’re about to turn, change lanes or stop.
When towing a trailer, the arrows on your
instrument panel will ash for turns even if the
bulbs on the trailer are burned out. Thus, you may
think drivers behind you are seeing your signal
when they are not. It’s important to check
occasionally to be sure the trailer bulbs are
still working.
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