2007 GMC ACADIA engine

{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 can run the engine to keep warm, but be
careful.
{CAUTION:
Snow can trap exhaust gases under your
vehicle. This can cause deadly CO (carbon
monoxide) gas to get inside. CO could
overcome you and kill you. You cannot see
it or smell it, so you might not know it is
in your vehicle. Clear away snow from
around the base of your vehicle, especially
any that is blocking the exhaust pipe.
And check around again from time to time
to be sure snow does not collect there.
Open a window just a little on the side of
the vehicle that is away from the wind.
This will help keep CO out.
Run the engine only as long as you must.
This saves fuel. When you run the engine, make it
go a little faster than just idle. That is, push the
accelerator slightly. This uses less fuel for the heat
that you get and it keeps the battery charged.
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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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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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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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You may go further and think you must limit
tongue weight to less than 1,000 lbs (454 kg) to
avoid exceeding GVWR. But, you must still
consider the effect on the rear axle. Because your
rear axle now weighs 3,100 lbs (1 406 kg), you
can only put 900 lbs (408 kg) on the rear axle
without exceeding RGAWR. The effect of tongue
weight is about 1.5 times the actual weight.
Dividing the 900 lbs (408 kg) by 1.5 leaves you
with being able to handle only 600 lbs (272 kg) of
tongue weight. Since tongue weight is usually
at least 10 percent of total loaded trailer weight,
you can expect that the largest trailer your vehicle
can properly handle is 6,000 lbs (2 721 kg).
It is important that you make sure your vehicle
does not exceed any of its ratings — GCWR,
GVWR, RGAWR, Maximum Trailer Rating
or Tongue Weight. The only way to be sure you
are not exceeding any of these ratings is to weigh
your vehicle and trailer.Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the upper
limit for cold tires. You’ll nd these numbers on the
Certication/Tire label. SeeLoading Your Vehicle
on page 361. Then be sure you don’t go over the
GVW limit for your vehicle, including the weight of
the trailer tongue.
Hitches
It’s important to have the correct hitch equipment.
Crosswinds, large trucks going by and rough
roads are a few reasons why you’ll need the
right hitch. Here are some rules to follow:
The rear bumper on your vehicle is not
intended for hitches. Do not attach rental
hitches or other bumper-type hitches to it.
Use only a frame-mounted hitch that does not
attach to the bumper.
Will you have to make any holes in the body of
your vehicle when you install a trailer hitch?
If you do, then be sure to seal the holes later
when you remove the hitch. If you don’t seal
them, deadly carbon monoxide (CO) from your
exhaust can get into your vehicle. SeeEngine
Exhaust on page 138. Dirt and water can, too.
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Driving on Grades
Your vehicle is designed primarily as a passenger
and load carrying vehicle. If you tow a trailer,
your vehicle will require more frequent
maintenance due to the additional load. Because
of the added load of the trailer, your vehicle’s
engine may overheat on hot days, when going up
a long or steep grade with a trailer. If the engine
coolant temperature gage indicates overheating,
turn off the air conditioning to reduce engine load,
pull off the road and stop in a safe spot.
Reduce speed and shift to a lower gear before
you start down a long or steep downgrade. If you
don’t shift down, you might have to use your
brakes so much that they would get hot and no
longer work well.
On a long uphill grade, shift down and reduce
your speed to around 55 mph (88 km/h) to reduce
the possibility of the engine and the transmission
overheating.
Parking on Hills
{CAUTION:
You really should not park your vehicle,
with a trailer attached, on a hill.
If something goes wrong, your rig could
start to move. People can be injured, and
both your vehicle and the trailer can be
damaged.
But if you ever have to park your rig on a hill,
here’s how to do it:
1. Apply your regular brakes, but don’t shift
into PARK (P).
When parking uphill, turn your wheels away
from the curb. When parking downhill,
turn your wheels into the curb.
2. Have someone place chocks behind the
trailer wheels.
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