2007 GMC ACADIA transmission

{CAUTION:
Coasting downhill in NEUTRAL (N) or with
the ignition off is dangerous. The brakes
will have to do all the work of slowing
down. They could get so hot that they
would not work well. You would then have
poor braking or even none going down a
hill. You could crash. Always have the
engine running and your vehicle in gear
when you go downhill.
Know how to go down hills. The most
important thing to know is this: let the engine
do some of the slowing down. Shift to a
lower gear when you go down a steep or
long hill.
Know how to go uphill. You may want to shift
down to a lower gear. The lower gears help
cool the engine and transmission, and you can
climb the hill better.
Stay in your own lane when driving on
two-lane roads in hills or mountains. Do not
swing wide or cut across the center of the
road. Drive at speeds that let you stay in your
own lane.
As you go over the top of a hill, be alert.
There could be something in your lane,
like a stalled car or an accident.
You may see highway signs on mountains
that warn of special problems. Examples
are long grades, passing or no-passing zones,
a falling rocks area, or winding roads.
Be alert to these and take appropriate action.
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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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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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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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If You Do Decide to Pull a Trailer
If you do, here are some important points:
There are many different laws, including speed
limit restrictions, having to do with trailering.
Make sure your rig will be legal, not only where
you live but also where you’ll be driving.
A good source for this information can be state
or provincial police.
Consider using a sway control. You can ask a
hitch dealer/retailer about sway controls.
Don’t tow a trailer at all during the rst
500 miles (805 km) your new vehicle is driven.
Your engine, axle or other parts could be
damaged.
Then, during the rst 500 miles (805 km) that
you tow a trailer, don’t drive over 50 mph
(80 km/h) and don’t make starts at full throttle.
This helps your engine and other parts of
your vehicle wear in at the heavier loads.
Obey speed limit restrictions when towing a
trailer. Don’t drive faster than the maximum
posted speed for trailers, or no more than
55 mph (90 km/h), to save wear on your
vehicle’s parts.
You can tow in DRIVE (D). You may want to
shift the transmission to a lower gear selection
if the transmission shifts too often (e.g., under
heavy loads and/or hilly conditions). See
“Tow/Haul Mode” later in this section.
Three important considerations have to do with
weight:
the weight of the trailer
the weight of the trailer tongue
and the total weight on your vehicle’s tires
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Tow/Haul Mode
Tow/Haul is a feature that assists when pulling a
heavy trailer or a large or heavy load. The purpose
of the Tow/Haul mode is to:
Reduce the frequency and improve the
predictability of transmission shifts when pulling
a heavy trailer or a large or heavy load.
Provide the same solid shift feel when pulling a
heavy trailer or a large or heavy load as when
the vehicle is unloaded.
Improve control of vehicle speed while requiring
less throttle pedal activity when pulling a heavy
trailer or a large or heavy load.
Increase the charging system voltage to assist
in recharging a battery installed in a trailer.
Press this button on
the console to
enable/disable the
tow/haul mode.A light on the instrument
panel will come on to
indicate that tow/haul
mode has been
selected.
Tow/Haul may be turned off by pressing the
button again, at which time the indicator light on
the instrument panel will turn off. The vehicle
will automatically turn off Tow/Haul every time
it is started.
Tow/Haul is designed to be most effective when
the vehicle and trailer combined weight is at
least 75 percent of the vehicle’s Gross Combined
Weight Rating (GCWR). See Weight of the Trailer
later in this section. Tow/Haul is most useful
under the following driving conditions:
When pulling a heavy trailer or a large or
heavy load through rolling terrain.
When pulling a heavy trailer or a large or
heavy load in stop and go traffic.
When pulling a heavy trailer or a large or heavy
load in busy parking lots where improved low
speed control of the vehicle is desired.
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