2005 BUICK CENTURY oil

Notice:Your vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in your fuel
system and also damage the plastic and rubber
parts. That damage would not be covered under
your warranty.
Some gasolines that are not reformulated for low
emissions may contain an octane-enhancing additive
called methylcyclopentadienyl manganese tricarbonyl
(MMT); ask the attendant where you buy gasoline
whether the fuel contains MMT. General Motors does
not recommend the use of such gasolines. Fuels
containing MMT can reduce the life of spark plugs and
the performance of the emission control system may
be affected. The malfunction indicator lamp may turn on.
If this occurs, return to your authorized GM dealer
for service.Fuels in Foreign Countries
If you plan on driving in another country outside the
United States or Canada, the proper fuel may be hard
to nd. Never use leaded gasoline or any other fuel
not recommended in the previous text on fuel.
Costly repairs caused by use of improper fuel would not
be covered by your warranty.
To check the fuel availability, ask an auto club, or
contact a major oil company that does business in the
country where you will be driving.
5-7

Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
your vehicle. Static electricity discharge from
the container can ignite the gasoline vapor.
You can be badly burned and your vehicle
damaged if this occurs. To help avoid injury to
you and others:
Dispense gasoline only into
approved containers.
Do not ll a container while it is inside a
vehicle, in a vehicle’s trunk, pickup bed or
on any surface other than the ground.
Bring the ll nozzle in contact with the
inside of the ll opening before operating
the nozzle. Contact should be maintained
until the lling is complete.
Do not smoke while pumping gasoline.
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.
5-10

A. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-35.
B. Battery. SeeBattery on page 5-39.
C. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-94.
D. Remote Positive (+) Battery Terminal. SeeJump
Starting on page 5-40.
E. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-24.
F. Engine Coolant Recovery Tank. SeeCooling System
on page 5-27.
G. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-34.
H. Electric Engine Cooling Fan. SeeCooling System on
page 5-27.
I. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-13.
J. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-13.
K. Automatic Transaxle Fluid Dipstick. See “Checking
the Fluid Level” underAutomatic Transaxle Fluid
on page 5-19.
L. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 5-36.
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.
SeeEngine 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

When to Add Engine Oil
If the oil is at or below the cross-hatched area at the
tip of the dipstick, then you will need to add at least
one quart of oil. But you must use the right kind.
This section explains what kind of oil to use.
For engine oil crankcase capacity, seeCapacities and
Specications on page 5-96.
Notice:Do not add too much oil. If your engine
has so much oil that the oil level gets above
the cross-hatched area that shows the proper
operating range, your engine could be damaged.SeeEngine Compartment
Overview on page 5-12
for the location of the
engine oil ll cap.
Be sure to add enough oil to put the level somewhere
in the proper operating range in the cross-hatched
area. Push the dipstick all the way back in when you
are through.
What Kind of Engine Oil to Use
Look for two things:
GM6094M
Your vehicle’s engine requires oil meeting GM
Standard GM6094M. You should look for and use
only an oil that meets GM Standard GM6094M.
5-14

SAE 5W-30
As shown in the viscosity chart, SAE 5W-30 is best
for your vehicle. However, if it is going to be 0°F
(–18°C) or above and SAE 5W-30 is not available,
you may use SAE 10W-30.
These numbers on an oil container show its
viscosity, or thickness. Do not use other viscosity
oils such as SAE 20W-50.
Oils meeting these
requirements should also
have the starburst
symbol on the container.
This symbol indicates
that the oil has been
certied by the American
Petroleum Institute (API).
You should look for this information on the oil container,
and useonlythose oils that are identied as meeting
GM Standard GM6094M and have the starburst symbol
on the front of the oil container.
5-15

Notice:Use only engine oil identied as meeting
GM Standard GM6094M and showing the American
Petroleum Institute Certied For Gasoline Engines
starburst symbol. Failure to use the recommended
oil can result in engine damage not covered by
your warranty.
GM Goodwrench
®oil meets all the requirements for
your vehicle.
If you are in an area of extreme cold, where the
temperature falls below−20°F (−29°C), it is
recommended that you use either an SAE 5W-30
synthetic oil or an SAE 0W-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Do not add anything to your oil. The recommended oils
with the starburst symbol that meet GM Standard
GM6094M are all you will need for good performance
and engine protection.
Engine Oil Life System
When to Change Engine Oil
Your vehicle has a computer system that lets you know
when to change the engine oil and lter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change will be indicated can vary
considerably. For the oil life system to work properly, you
must reset the system every time the oil is changed.
When the system has calculated that oil life has been
diminished, it will indicate that an oil change is
necessary. A CHANGE OIL SOON light will come on.
Change your oil as soon as possible within the next
two times you stop for fuel. It is possible that, if you are
driving under the best conditions, the oil life system
may not indicate that an oil change is necessary for over
a year. However, your engine oil and lter must be
changed at least once a year and at this time the system
must be reset. Your dealer has GM-trained service
people who will perform this work using genuine GM
parts and reset the system. It is also important to check
your oil regularly and keep it at the proper level.
If the system is ever reset accidentally, you must change
your oil at 3,000 miles (5 000 km) since your last oil
change. Remember to reset the oil life system whenever
the oil is changed.
5-16

How to Reset the CHANGE OIL
SOON Light
The GM Oil Life System calculates when to change
your engine oil and lter based on vehicle use.
Anytime your oil is changed, reset the system so it can
calculate when the next oil change is required. If a
situation occurs where you change your oil prior to a
CHANGE OIL SOON light being turned on, reset
the system.
After changing the engine oil, reset the system by
performing the following steps:
1. Turn the ignition key to RUN with the engine off.
2. Fully press and release the accelerator pedal slowly
three times within ve seconds.
If the CHANGE OIL SOON light ashes, the system
is resetting.
3. Turn the key to OFF, then start the vehicle. The oil
life will change to 100 percent.
If the CHANGE OIL SOON light comes back on
when you start your vehicle, the engine oil life
system has not reset. Repeat the procedure.
What to Do with Used Oil
Used engine oil contains certain elements that may be
unhealthy for your skin and could even cause cancer.
Do not let used oil stay on your skin for very long. Clean
your skin and nails with soap and water, or a good
hand cleaner. Wash or properly dispose of clothing or
rags containing used engine oil. See the manufacturer’s
warnings about the use and disposal of oil products.
Used oil can be a threat to the environment. If you
change your own oil, be sure to drain all the oil from the
lter before disposal. Never dispose of oil by putting it
in the trash, pouring it on the ground, into sewers, or into
streams or bodies of water. Instead, recycle it by
taking it to a place that collects used oil. If you have a
problem properly disposing of your used oil, ask
your dealer, a service station or a local recycling
center for help.
5-17

Engine Air Cleaner/Filter
SeeEngine Compartment Overview on page 5-12
for the location of the engine air cleaner/lter.
When to Inspect the Engine
Air Cleaner/Filter
Inspect the air cleaner/lter at every oil change and
replace at the rst oil change after 25,000 miles
(40 000 km).
How to Inspect the Engine Air
Cleaner/Filter
To inspect the air cleaner/lter remove the lter from
the vehicle and lightly shake the lter to release
loose dust and dirt. If the lter remains caked with dirt,
a new lter is required.To inspect or replace the engine air cleaner/lter,
do the following:
1. Loosen the screw and clamp on the air duct.
2. Lift the two clips
located on the top of
the lter assembly
to unlock the cover.
3. Disconnect the duct and reposition it while removing
the cover.
4. Inspect or replace the engine air cleaner/lter.
5. Reinstall the air duct and cover by reversing
Steps 1 to 3.
5-18