2007 GMC ACADIA ECU

Winter Driving
Here are some tips for winter driving:
Have your vehicle in good shape for winter.
You may want to put winter emergency
supplies in your vehicle.
Also seeTires on page 435.Include an ice scraper, a small brush or broom,
a supply of windshield washer uid, a rag,
some winter outer clothing, a small shovel, a
ashlight, a red cloth, and a couple of reective
warning triangles. And, if you will be driving under
severe conditions, include a small bag of sand,
a piece of old carpet, or a couple of burlap bags to
help provide traction. Be sure you properly
secure these items in your vehicle.
356

To nd out the actual loads on your front and rear
axles, you need to go to a weigh station and
weigh your vehicle. Your dealer/retailer can help
you with this. Be sure to spread out your load
equally on both sides of the centerline.
Never exceed the GVWR for your vehicle or the
GAWR for either the front or rear axle.
{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.
Notice:Overloading your vehicle may cause
damage. Repairs would not be covered by your
warranty. Do not overload your vehicle.If you put things inside your vehicle — like
suitcases, tools, packages, or anything else, they
will go as fast as the vehicle goes. If you have
to stop or turn quickly, or if there is a crash, they
will keep going.
{CAUTION:
Things you put inside your vehicle can
strike and injure people in a sudden stop
or turn, or in a crash.
Put things in the cargo area of your
vehicle. Try to spread the weight
evenly.
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 your vehicle.
When you carry something inside the
vehicle, secure it whenever you can.
Do not leave a seat folded down
unless you need to.
366

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.
368

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.
374

Safety Chains
You should always attach chains between your
vehicle and your trailer. Cross the safety
chains under the tongue of the trailer so that the
tongue will not drop to the road if it becomes
separated from the hitch. Instructions about safety
chains may be provided by the hitch manufacturer
or by the trailer manufacturer. Follow the
manufacturer’s recommendation for attaching
safety chains and do not attach them to the
bumper. Always leave just enough slack so you
can turn with your rig. And, never allow safety
chains to drag on the ground.
Trailer Brakes
If you tow more than 1,000 lbs (450 kg), use trailer
brakes. Because your vehicle has anti-lock brakes,
don’t try to tap into your vehicle’s hydraulic brake
system. If you do, both brake systems won’t
work well, or at all.
Be sure to read and follow the instructions for the
trailer brakes so you’ll be able to install, adjust
and maintain them properly.
Driving with a Trailer
Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you’ll want to get to know your rig. Acquaint
yourself with the feel of handling and braking with
the added weight of the trailer. And always
keep in mind that the vehicle you are driving is
now a good deal longer and not nearly as
responsive as your vehicle is by itself.
Before you start, check all trailer hitch parts and
attachments, safety chains, electrical connector,
lamps, tires and mirror adjustment. If the trailer has
electric brakes, start your vehicle and trailer moving
and then apply the trailer brake controller by hand
to be sure the brakes are working. This lets you
check your electrical connection at the same time.
During your trip, check occasionally to be sure
that the load is secure, and that the lamps and any
trailer brakes are still working.
Following Distance
Stay at least twice as far behind the vehicle ahead
as you would when driving your vehicle without
a trailer. This can help you avoid situations
that require heavy braking and sudden turns.
378

Radiator Pressure Cap
Notice:If the pressure cap is not tightly
installed, coolant loss and possible engine
damage may occur. Be sure the cap is properly
and tightly secured.
SeeEngine Compartment Overview on page 396
for more information on location.
Engine Overheating
There is an engine coolant temperature gage on
your vehicle’s instrument panel. SeeEngine
Coolant Temperature Gage on page 225.
Your vehicle may also have an ENGINE
OVERHEATED IDLE ENGINE and ENGINE
OVERHEATED STOP ENGINE message
displayed in the Driver Information Center (DIC).
SeeDIC Warnings and Messages on page 244.
If Steam Is Coming From Your Engine
{CAUTION:
Steam from an overheated engine can
burn you badly, even if you just open the
hood. Stay away from the engine if you
see or hear steam coming from it. Turn it
off and get everyone away from the
vehicle until it cools down. Wait until
there is no sign of steam or coolant
before you open the hood.
CAUTION: (Continued)
410

5. Fill the coolant recovery tank to the FULL
COLD mark.
6. Reinstall the cap on the coolant recovery tank,
but leave the radiator pressure cap off.7. Start the engine and let it run until you can
feel the upper radiator hose getting hot.
Watch out for the engine cooling fan.
8. By this time, the coolant level inside the
radiator ller neck may be lower. If the level is
lower, add more of the proper DEX-COOL
®
coolant mixture through the ller neck until the
level reaches the base of the ller neck.
Replace the pressure cap.
At any time during this procedure if coolant begins
to ow out of the ller neck, reinstall the pressure
cap. Be sure to secure it tightly.
418

Removing the Flat Tire and
Installing the Spare Tire
1. It is recommended that you do a safety check
before preceding. SeeChanging a Flat Tire
on page 458for more information.
2. If the vehicle has a wheel cover, loosen the
plastic nut caps with the wheel wrench.
They will not come off. Then, using the at
end of the wheel wrench, pry along the edge
of the cover until it comes off. Be careful;
the edges may be sharp. Do not try to remove
the cover with your bare hands.
Store the wheel cover securely in the rear of
the vehicle until you have the at tire
repaired or replaced.
If your vehicle has aluminum wheels, remove
the wheel nut caps using the wheel wrench.3. Loosen the wheel nuts — but do not
remove them — using the lug wrench.
For wheels with a wheel lock key, use the
wheel lock key between the lock nut and
lug wrench. The key is supplied in the front
passenger door pocket.
Notice:If your vehicle has wheel locks and an
impact wrench is used to remove the wheel
nuts, the lock nut or wheel lock key could be
damaged. Do not use an impact wrench to
remove the wheel nuts if your vehicle has
wheel locks.
463