2004 BUICK CENTURY brake

Turn Signals When Towing a Trailer
When towing a trailer, the vehicle may need a different
turn signal asher and/or extra wiring. Check with
your dealer. The arrows on the instrument panel will
ash whenever signaling 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 the instrument
panel will ash for turns even if the bulbs on the trailer
are burned out. 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 gearbeforestarting
down a long hill or steep downgrade. If the vehicle
is not shifted down, the brakes might have to be
used so much that they would get hot and no longer
work well.
On a long uphill grade, shift down and reduce the
vehicle’s speed to around 45 mph (70 km/h) to reduce
the possibility of engine and transaxle overheating.
If towing a trailer, you may want to drive in THIRD (3)
instead of AUTOMATIC OVERDRIVE (
X). Shift
to a lower gear as needed.
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 the rig ever has to be parked on a hill, here is
how to do it:
1. Apply the regular brakes, but do not shift into
PARK (P) yet.
2. Have someone place chocks under the trailer’s
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 the parking
brake, and shift to PARK (P).
5. Release the regular brakes.
4-44

When You Are Ready to Leave After
Parking on a Hill
1. Apply the regular brakes and hold the pedal down
while you:
Start the 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
The vehicle will need service more often when it pulls a
trailer. See.Scheduled Maintenance on page 6-4for
more information. Things that are especially important in
trailer operation are automatic transaxle uid; which
should not be overlled; engine oil, drive belt, cooling
system, and brake system. Each of these is covered
in this manual, and the Index will help you nd
them quickly. If trailering, it is a good idea to review this
information before starting on a trip.
Check periodically to see that all hitch nuts and bolts
are tight.
Engine Cooling When Trailer Towing
The cooling system may temporarily overheat during
severe operating conditions. SeeEngine Overheating on
page 5-25.
4-45

Service............................................................5-3
Doing Your Own Service Work.........................5-3
Adding Equipment to the Outside of Your
Vehicle......................................................5-4
Fuel................................................................5-4
Gasoline Octane............................................5-4
Gasoline Specications....................................5-5
California Fuel...............................................5-5
Additives.......................................................5-6
Fuels in Foreign Countries...............................5-6
Filling Your Tank............................................5-7
Filling a Portable Fuel Container.......................5-9
Checking Things Under the Hood....................5-10
Hood Release..............................................5-10
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-13
Engine Air Cleaner/Filter................................5-18
Automatic Transaxle Fluid..............................5-19
Engine Coolant.............................................5-22
Radiator Pressure Cap..................................5-25
Engine Overheating.......................................5-25
Cooling System............................................5-28
Power Steering Fluid.....................................5-35
Windshield Washer Fluid................................5-36
Brakes........................................................5-38Battery........................................................5-41
Jump Starting...............................................5-42
Headlamp Aiming...........................................5-49
Bulb Replacement..........................................5-51
Halogen Bulbs..............................................5-51
Headlamps..................................................5-51
Front Turn Signal and Parking Lamps..............5-52
Center High-Mounted Stoplamp (CHMSL).........5-53
Taillamps, Turn Signal, and Stoplamps............5-54
Back-Up Lamps............................................5-55
Windshield Wiper Blade Replacement..............5-56
Tires..............................................................5-57
Ination - Tire Pressure.................................5-64
Tire Pressure Monitor System.........................5-65
Tire Inspection and Rotation...........................5-67
When It Is Time for New Tires.......................5-68
Buying New Tires.........................................5-69
Uniform Tire Quality Grading..........................5-70
Wheel Alignment and Tire Balance..................5-71
Wheel Replacement......................................5-72
Tire Chains..................................................5-73
If a Tire Goes Flat........................................5-74
Changing a Flat Tire.....................................5-75
Compact Spare Tire......................................5-87
Section 5 Service and Appearance Care
5-1

Checking Things Under
the Hood
{CAUTION:
An electric fan under the hood can start up
and injure you even when the engine is not
running. Keep hands, clothing and tools away
from any underhood electric fan.
{CAUTION:
Things that burn can get on hot engine parts
and start a re. These include liquids like fuel,
oil, coolant, brake uid, windshield washer and
other uids, and plastic or rubber. You or
others could be burned. Be careful not to drop
or spill things that will burn onto a hot engine.
Hood Release
To open the hood, do the following:
1. Pull the interior hood
release handle located
below the instrument
panel, to the left of the
steering column.
5-10

A. Windshield Washer Fluid Reservoir. SeeWindshield
Washer Fluid on page 5-36.
B. Battery. SeeBattery on page 5-41.
C. Underhood Fuse Block. SeeFuses and Circuit
Breakers on page 5-97.
D. Remote Positive (+) Battery Terminal. SeeJump
Starting on page 5-42.
E. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-25.
F. Engine Coolant Recovery Tank. SeeEngine Coolant
on page 5-22.
G. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-35.
H. Electric Engine Cooling Fan. SeeJump Starting on
page 5-42.
I. Engine Oil Fill Cap. SeeEngine Oil on page 5-13.
J. Engine Oil Dipstick. SeeEngine Oil on page 5-13.
K. Automatic Transaxle Fluid Dipstick. SeeAutomatic
Transaxle Fluid on page 5-19.
L. Brake Fluid Reservoir. SeeBrakes on page 5-38.
M. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-18.Engine Oil
Checking Engine Oil
It is a good idea to check your engine oil every time you
get fuel. In order to get an accurate reading, the oil
must be warm and the vehicle must be on level ground.
The engine oil dipstick handle is a yellow loop. See
Engine Compartment Overview on page 5-12for
the location of the engine oil dipstick.
Turn off the engine and give the oil several minutes to
drain back into the oil pan. If you don’t, the oil
dipstick might not show the actual level.
Pull out the dipstick and clean it with a paper towel or
cloth, then push it back in all the way. Remove it again,
keeping the tip down, and check the level.
5-13

How to Check
Because this operation can be a little difficult, you may
choose to have this done at the dealership service
department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
Notice:Too much or too little uid can damage the
transaxle. Too much can mean that some of the
uid could come out and fall on hot engine or
exhaust system parts, starting a re. Too little uid
could cause the transaxle to overheat. Be sure
to get an accurate reading if you check the transaxle
uid.
Wait at least 30 minutes before checking the transaxle
uid level if you have been driving:
When outside temperatures are above 90°F (32°C).
At high speed for quite a while.
In heavy traffic – especially in hot weather.
While pulling a trailer.To get the right reading, the uid should be at
normal operating temperature, which is 180°F
to 200°F (82°C to 93°C).
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it is colder than 50°F (10°C), you may have to
drive longer.
Checking the Fluid Level
Prepare the vehicle as follows:
Park the vehicle on a level place. Keep the engine
running.
With the parking brake applied, place the shift lever
in PARK (P).
With your foot on the brake pedal, move the shift
lever through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK (P).
Let the engine run at idle for three to ve minutes.
Then, without shutting off the engine, follow these steps:
5-20

Brakes
Brake Fluid
Your brake master cylinder reservoir is lled with DOT-3
brake uid. SeeEngine Compartment Overview on
page 5-12for the location of the reservoir.
There are only two reasons why the brake uid level in
the reservoir might go down. The rst is that the
brake uid goes down to an acceptable level duringnormal brake lining wear. When new linings are put in,
the uid level goes back up. The other reason is
that uid is leaking out of the brake system. If it is, you
should have your brake system xed, since a leak
means that sooner or later your brakes will not work
well, or will not work at all.
So, it is not a good idea to “top off” your brake uid.
Adding brake uid will not correct a leak. If you add uid
when your linings are worn, then you will have too
much uid when you get new brake linings. You should
add (or remove) brake uid, as necessary, only when
work is done on the brake hydraulic system.
{CAUTION:
If you have too much brake uid, it can spill on
the engine. The uid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
uid only when work is done on the brake
hydraulic system.
5-38

When your brake uid falls to a low level, your brake
warning light will come on. SeeBrake System Warning
Light on page 3-32.
What to Add
When you do need brake uid, use only DOT-3 brake
uid. Use new brake uid from a sealed container
only. SeeRecommended Fluids and Lubricants on
page 6-12.
Always clean the brake uid reservoir cap and the area
around the cap before removing it. This will help
keep dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in your brake
system, your brakes may not work well, or
they may not even work at all. This could
cause a crash. Always use the proper brake
uid.
Notice:
Using the wrong uid can badly damage brake
system parts. For example, just a few drops of
mineral-based oil, such as engine oil, in your
brake system can damage brake system
parts so badly that they will have to be replaced.
Do not let someone put in the wrong kind of
uid.
If you spill brake uid on your vehicle’s painted
surfaces, the paint nish can be damaged. Be
careful not to spill brake uid on your vehicle. If
you do, wash it off immediately. SeeAppearance
Care on page 5-88. United States
Canada
5-39