2007 BUICK TERRAZA Owner's Manual

Dinghy Towing
Your vehicle was not designed to be towed with
all of its wheels on the ground. It can be towed
with the two rear wheels on the ground. See “Dolly
Towing” following for more information.
Dolly Towing
To dolly tow your vehicle, do the following:
1. Put the front wheels on a dolly.
2. Put the vehicle in 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.
Level Control
With this feature, the rear of the vehicle is
automatically kept level as you load or unload
your vehicle. However, you should still not exceed
the GVWR or the GAWR. SeeLoading Your
Vehicle on page 378.
You may hear the compressor operating when you
load or unload your vehicle, and periodically as
the system self-adjusts. This is normal. The
compressor should operate for brief periods of
time. If the sound continues for an extended period
of time, your vehicle needs service.
Using heavier suspension components to get
added durability might not change your weight
ratings. Ask your dealer to help you load
your vehicle the right way.
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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.
Pull a trailer only if you have followed all
the steps in this section. Ask your dealer
for advice and information about towing a
trailer with your vehicle.
Notice:Pulling a trailer improperly can
damage your vehicle and result in costly
repairs that would not be covered by your
warranty. Always follow the instructions in this
section and check with your dealer for more
information about towing a trailer with
your vehicle.Your vehicle can tow a trailer. To identify the
trailering capacity of your vehicle, you should read
the information in “Weight of the Trailer” that
appears later in this section. 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 is the reason for this section. 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,
transaxle, 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. The trailer also 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. See “Hitches”
later in this section.
Do not tow a trailer at all during the rst
500 miles (800 km) your new vehicle is driven.
Your engine, axle, or other parts could be
damaged.
During the rst 500 miles (800 km) that you
tow a trailer, do not drive over 50 mph
(80 km/h) and do not make starts at full
throttle. This helps your engine and other parts
of your vehicle wear in at the heavier loads.
You can use THIRD (3) or, as you need to, a
lower gear when towing a trailer. Operating
your vehicle in THIRD (3) when towing a trailer
will minimize heat buildup and extend the
life of your transaxle.Three important considerations have to do with
weight:
Weight of the trailer
Weight of the trailer tongue
Weight on your vehicle’s tires
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 must be subtracted from the maximum
trailer weight.
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Look in the following chart to nd the maximum trailer weight for your vehicle.
Vehicle Axle RatioMaximum Trailer
Weight *GCWR
Two-Wheel-Drive 3.29 3,500 lbs (1 588 kg) 8,500 lbs (3 856 kg)
Any vehicle without the V92 trailering package or heavy-duty cooling package is limited to a 2,000 lb (907 kg) trailer
rating and a 7,000 lb (3 175 kg) GCWR.
*The Gross Combination Weight Rating (GCWR) is the total allowable weight of the completely loaded vehicle and
trailer including any passengers, cargo, equipment and conversion. The GCWR for your vehicle should not be
exceeded.
You can ask your dealer for our trailering
information or advice, or you can contact the
Customer Assistance Center. SeeCustomer
Assistance Offices on page 530for more
information.
In Canada, write to:
General Motors of Canada Limited
Customer Communication Center, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7Weight of the Trailer Tongue
The tongue load (A) of any trailer is an important
weight to measure because it affects the total
or gross weight of your vehicle. The Gross Vehicle
Weight (GVW) includes the curb weight of the
vehicle, any cargo you may carry in it, and
the people who will be riding in the vehicle. If you
have a lot of options, equipment, passengers,
or cargo in your vehicle, it will reduce the tongue
weight your vehicle can carry, which will also
reduce the trailer weight your vehicle can tow. And
if you will tow a trailer, you must add the tongue
load to the GVW because your vehicle will be
carrying that weight, too. SeeLoading Your
Vehicle on page 378for more information about
your vehicle’s maximum load capacity.
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If you are using a weight-carrying or a
weight-distributing hitch, the trailer tongue
weight (A) should be 10 percent to 15 percent of
the total loaded trailer weight (B). Do not exceed
the maximum allowable tongue weight of 350 lbs
(159 kg) for your vehicle.
After you have loaded your trailer, weigh the trailer
and then the tongue, separately, to see if the
weights are proper. If they are not, you may be able
to get them right simply by moving some items
around in the trailer.
Trailering may be limited by the vehicle’s ability to
carry tongue weight. Tongue weight cannot cause
the vehicle to exceed the GVWR (Gross Vehicle
Weight Rating) or the RGAWR (Rear Gross Axle
Weight Rating).The effect of additional weight may reduce your
trailering capacity more than the total of the
additional weight.
Consider the following example:
A vehicle model base weight is 5,500 lbs
(2 495 kg); 2,800 lbs (1 270 kg) at the front axle
and 2,700 lbs (1 225 kg) at the rear axle. It has a
GVWR of 7,200 lbs (3 266 kg), a RGAWR of
4,000 lbs (1 814 kg) and a GCWR (Gross
Combination Weight Rating) of 14,000 lbs
(6 350 kg). The trailer rating should be:
You can expect tongue weight to be at least
10 percent of trailer weight (850 lbs (386 kg)) and
because the weight is applied well behind the
rear axle, the effect on the rear axle will be greater
than just the weight itself, as much as 1.5 times
as much.
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The weight at the rear axle could be 850 lbs
(386 kg) X 1.5 = 1,275 lbs (578 kg). Since the rear
axle already weighs 2,700 lbs (1 225 kg), adding
1,275 lbs (578 kg) brings the total to 3,975 lbs
(1 803 kg). This is very close to, but within the limit
for RGAWR as well. The vehicle is set to trailer
up to 8,500 lbs (3 856 kg).
But let’s say your specic vehicle is equipped with
some of the latest options and you have a front
seat passenger and two rear seat passengers with
some luggage and gear in the vehicle as well.
You may add 300 lbs (136 kg) to the front
axle weight and 400 lbs (181 kg) to the rear axle
weight. Your vehicle now weighs:
Weight is still below 7,200 lbs (3 266 kg) and you
may think that you should subtract 700 additional
pounds (318 kg) from your trailering capacity
to stay within GCWR limits.Your maximum trailer would only be 7,800 lbs
(3 538 kg). 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.
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Total Weight on Your Vehicle’s Tires
Be sure your vehicle’s tires are inated to the
upper limit for cold tires. You will nd these
numbers on the Certication/Tire label at the rear
edge of the driver’s door or seeLoading Your
Vehicle on page 378. Then be sure you do not go
over the GVW limit for your vehicle, including
the weight of the trailer tongue.
Hitches
It is important to have the correct hitch equipment.
Crosswinds, large trucks going by, and rough
roads are a few reasons why you will need
the right hitch. Here are some rules to follow:
The bumpers on your vehicle are not intended
for hitches. Do not attach rental hitches or
other bumper-type hitches to them. 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, remember to seal the holes later
when you remove the hitch. If you do not seal
them, deadly carbon monoxide (CO) from
your exhaust can get into your vehicle. See
Engine Exhaust on page 141. Dirt and
water can, too.
Safety Chains
You should always attach chains between your
vehicle and your trailer. Cross the safety
chains under the tongue of the trailer to help
prevent the tongue from contacting 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. Never allow safety
chains to drag on the ground.
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Trailer Brakes
If your trailer weighs more than 1,000 lbs (450 kg)
loaded, then it needs its own brakes – and they
must be adequate. Be sure to read and follow the
instructions for the trailer brakes so you will be
able to install, adjust, and maintain them properly.
Because your vehicle has anti-lock brakes, do not
try to tap into your vehicle’s brake system. If you do,
both brake systems will not work well, or at all.
Driving with a Trailer
{CAUTION:
If you have a rear-most window open and
you pull a trailer with your vehicle, carbon
monoxide (CO) could come into your
CAUTION: (Continued)
CAUTION: (Continued)
vehicle. You cannot see or smell CO. It
can cause unconsciousness or death. See
Engine Exhaust on page 141. To maximize
your safety when towing a trailer:
Have your exhaust system inspected
for leaks, and make necessary repairs
before starting on your trip.
Keep the rear-most windows closed.
If exhaust does come into your vehicle
through a window in the rear or
another opening, drive with your front,
main heating or cooling system on
and with the fan on any speed. This
will bring fresh, outside air into your
vehicle. Do not use the climate control
setting for maximum air because it
only recirculates the air inside your
vehicle. SeeClimate Control System
on page 193orDual Climate Control
System on page 197.
392