2007 BUICK TERRAZA trailer

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.
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Towing a trailer requires a certain amount of
experience. Before setting out for the open road,
you will 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.
Passing
You will need more passing distance up ahead
when you are towing a trailer. And, because
you are a good deal longer, you will 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.
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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 are turning with a trailer, make wider
turns than normal. Do this so your trailer will
not 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 has to have
extra wiring.
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 are 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 is important to check
occasionally to be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower gear before
you start down a long or steep downgrade. If you
do not shift down, you might have to use your
brakes so much that they would get hot and
no longer work well.
If you are towing a trailer that weighs more than
1,000 lbs (450 kg), you may prefer to drive in
THIRD (3) instead of DRIVE (D) or, as you need
to, a lower gear. This will minimize heat build-up
and extend the life of your transaxle.
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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, do
the following:
1. Apply your regular brakes, but do not shift into
PARK (P).
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release
the regular brakes until the chocks absorb
the load.
4. Reapply the regular brakes. Then apply your
parking brake, and shift into PARK (P).
5. Release the regular brakes.
When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal
down while you do the following:
Start your engine.
Shift into a gear.
Release the parking brake.
2. Let up on the brake pedal.
3. Drive slowly until the trailer is clear of the
chocks.
4. Stop and have someone pick up and store the
chocks.
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Maintenance When Trailer Towing
Your vehicle will need service more often when
you are pulling a trailer. See the Maintenance
Schedule for more on this. Things that are
especially important in trailer operation are
automatic transaxle uid, engine oil, belts, cooling
system, and brake system. Each of these is
covered in this manual, and the Index will help
you nd them quickly. If you are trailering, it is a
good idea to review these sections before you
start your trip.Check periodically to see that all hitch nuts and
bolts are tight.
Trailer Wiring Harness
Your vehicle may have a trailer wiring harness
package located in the glove box. It can be
connected from the rear of your vehicle to your
trailer. Contact your dealer for more information.
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