2006 BUICK RANDEZVOUS trailer

Trailering may also 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.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.
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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 will nd these numbers on
the Certication/Tire Label at the rear edge of the
driver’s door, or seeLoading Your Vehicle on page 4-31.
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:
If you will be pulling a trailer that, when loaded, will
weigh more than 2,000 lbs (900 kg), use a properly
mounted, weight-carrying hitch and sway control
of the proper size. This equipment is very important
for proper vehicle loading and good handling
while driving.
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 when you
remove the hitch. If you do not seal them, deadly
carbon monoxide (CO) from your exhaust can
get into your vehicle. SeeEngine Exhaust
on page 2-29. Dirt and water can, too.
4-43

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.
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 may have 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 vehicle.
You cannot see or smell CO. It can cause
unconsciousness or death. SeeEngine
Exhaust on page 2-29. 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 3-28.
4-44

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.
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.
4-45

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), drive in AUTOMATIC OVERDRIVE (D) or,
as you need to, a lower gear. This will minimize heat
build-up and extend the life of your transaxle.
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) yet.
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 then shift to PARK (P).
5. Release the regular brakes.
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When You Are Ready to Leave After
Parking on a Hill
1. Apply your regular brakes and hold the pedal down
while you:
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.
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 located
at the rear of your vehicle. To use the trailer wiring
harness, you need a converter kit. Contact your dealer
for more information.
4-47

Gasoline Octane
If your vehicle has the 3.5L V6 engine (VIN Code 8),
use regular unleaded gasoline with a posted octane
rating of 87 or higher. If the octane rating is less than 87,
you may notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this occurs,
use a gasoline rated at 87 octane or higher as soon as
possible. If you are using gasoline rated at 87 octane
or higher and you hear heavy knocking, your engine
needs service.
If your vehicle has the 3.6L V6 engine (VIN Code 7),
use regular unleaded gasoline with a posted octane
rating of 87 or higher. For best performance or trailer
towing, you may choose to use middle grade 89 octane
unleaded gasoline. If the octane rating is less than 87,
you may notice an audible knocking noise when you
drive, commonly referred to as spark knock. If this occurs,
use a gasoline rated at 87 octane or higher as soon as
possible. If you are using gasoline rated at 87 octane
or higher and you hear heavy knocking, your engine
needs service.
Gasoline Specications
At a minimum, gasoline should meet ASTM
specication D 4814 in the United States or
CAN/CGSB-3.5 in Canada. Some gasolines may
contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT).
General Motors recommends against the use of
gasolines containing MMT. SeeAdditives on
page 5-6for additional information.
California Fuel
If your vehicle is certied to meet California Emissions
Standards, it is designed to operate on fuels that
meet California specications. See the underhood
emission control label. If this fuel is not available
in states adopting California emissions standards,
your vehicle will operate satisfactorily on fuels meeting
federal specications, but emission control system
performance may be affected. The malfunction
indicator lamp may turn on and your vehicle may fail
a smog-check test. SeeMalfunction Indicator Lamp
on page 3-46. If this occurs, return to your authorized
GM dealer for diagnosis. If it is determined that the
condition is caused by the type of fuel used, repairs
may not be covered by your warranty.
5-5

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. Just 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.
If you keep driving when your engine is
overheated, the liquids in it can catch re.
You or others could be badly burned. Stop
your engine if it overheats, and get out of the
vehicle until the engine is cool.
SeeOverheated Engine Protection Operating
Mode on page 5-25for information on driving
to a safe place in an emergency.Notice:If your engine catches re because you
keep driving with no coolant, your vehicle can
be badly damaged. The costly repairs would not be
covered by your warranty. SeeOverheated Engine
Protection Operating Mode on page 5-25for
information on driving to a safe place in an
emergency.
If No Steam Is Coming From Your
Engine
If you get an engine overheat warning but see or
hear no steam, the problem may not be too serious.
Sometimes the engine can get a little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
5-24