PONTIAC GRAND PRIX 2004 Owners Manual

Loading Your Vehicle
Two labels on your vehicle show how much weight it
may properly carry. The Tire-Loading Information label is
on the inside of the trunk lid. The label tells you the
proper size, speed rating and recommended in¯ation
pressures for the tires on your vehicle. It also gives
you important information about the number of people
that can be in your vehicle and the total weight you can
carry. This weight is called the vehicle capacity weight
and includes the weigh of all occupants, cargo and
all non-factory installed options.The other label is the Certi®cation label, found on the
rear edge of the driver's door. It tells you the gross
weight capacity of your vehicle, called the Gross Vehicle
Weight Rating (GVWR). The GVWR includes the
weight of the vehicle, all occupants, fuel and cargo.
Never exceed the GVWR for your vehicle or the Gross
Axle Weight Rating (GAWR) for either the front or
rear axle.
4-35

If you do have a heavy load, spread it out. Don't carry
more than 167 lbs (75 kg) in your trunk.
{CAUTION:
Do not load your vehicle any heavier than the
GVWR, or either the maximum front or rear
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:Your warranty does not cover parts or
components that fail because of overloading.
If you put things inside your vehicle Ð like suitcases,
tools, packages or anything else Ð they will go as fast
as the vehicle goes. If you have to stop or turn
quickly, or if there is a crash, they'll 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 trunk of your vehicle. In a
trunk, put them as far forward as you can.
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.
·Don't leave an unsecured child restraint in
your vehicle.
·When you carry something inside the
vehicle, secure it whenever you can.
·Don't leave a seat folded down unless you
need to.
4-36

Towing a Trailer
{CAUTION:
If you don't 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 Ð 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 for advice and information
about towing a trailer with your vehicle.Your vehicle can tow a trailer if it is equipped with the
proper trailer towing equipment. To identify what
the vehicle trailering capacity is for your vehicle, you
should read the information in ªWeight of the Trailerº that
appears later in this section. But trailering is different
than just driving your vehicle by itself. Trailering means
changes in handling, 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, 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. 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 about sway controls.
·Don't tow a trailer at all during the ®rst 1,000 miles
(1 600 km) your new vehicle is driven. Your engine,
axle or other parts could be damaged.
·Then, during the ®rst 500 miles (800 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.
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.
Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than 1000 lbs (454 kg).
But even that can be too heavy.
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. And, it can also depend on any special
equipment that you have on your vehicle.
You can ask your dealer for our trailering information or
advice, or you can write us at:
Pontiac-GMC Customer Assistance Center
P.O. Box 33172
Detroit, MI 48232-5172
In Canada, write to:
General Motors of Canada Limited
Customer Communication Centre, 163-005
1908 Colonel Sam Drive
Oshawa, Ontario L1H 8P7
4-38

Weight 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. And if you tow a trailer, you must add the
tongue load to the GVW because your vehicle will
be carrying that weight, too. See
Loading Your Vehicle
on page 4-35for more information about your
vehicle's maximum load capacity.If you're using a weight-carrying hitch or a
weight-distributing hitch, the trailer tongue (A)
should weigh 10 to 15 percent of the total loaded
trailer weight (B).
After you've loaded your trailer, weigh the trailer and then
the tongue, separately, to see if the weights are proper.
If they aren't, you may be able to get them right simply by
moving some items around in the trailer.Total Weight on Your Vehicle's Tires
Be sure your vehicle's tires are in¯ated to the upper
limit for cold tires. You'll ®nd these numbers on the
Tire Loading Information label, found on the inside of the
trunk lid, or see
Loading Your Vehicle on page 4-35.
Then be sure you don't go over the GVW limit for your
vehicle, including the weight of the trailer tongue.
4-39

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. See
Engine Exhaust
on page 2-31. 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 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
Because you have anti-lock brakes, do not try to tap
into your vehicle's brake system. If you do, both brake
systems won't work well, or at all.
4-40

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 the trailer hitch and platform
(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'll need more passing distance up ahead when
you're towing a trailer. And, because you're a good
deal longer, you'll 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.
4-41

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're turning with a trailer, make wider turns than
normal. Do this so your trailer won't 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 may need a
different turn signal ¯asher and/or extra wiring.
Check with your dealer. 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're 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's
important to check occasionally to be sure the trailer
bulbs are still working.Your vehicle has bulb warning lights. When you plug
a trailer lighting system into your vehicle's lighting
system, its bulb warning lights may not let you know if
one of your lamps goes out. So, when you have a trailer
lighting system plugged in, be sure to check your
vehicle and trailer lamps from time to time to be sure
they're all working. Once you disconnect the trailer
lamps, the bulb warning lights again can tell you if one
of your vehicle lamps is out.
Driving On Grades
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 45 mph (70 km/h) to reduce the
possibility of engine and transaxle overheating.
If you have overdrive, you may have to drive in
THIRD (3) instead of AUTOMATIC OVERDRIVE (D).
4-42

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) 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.
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, and
·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.
4-43

Maintenance When Trailer Towing
Your vehicle will need service more often when you're
pulling a trailer. SeePart A: Scheduled Maintenance
Services on page 6-4for more information. Things that
are especially important in trailer operation are automatic
transaxle ¯uid (don't over®ll), engine oil, drive 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're trailering, it's a good idea to review
this information before you start your trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
Your cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating
on page 5-29.
4-44