
Black plate (8,1)Buick Lucerne Owner Manual - 2011
Many service stations will not have an 85% ethanol
fuel (E85) pump available. The U.S. Department
of Energy has an alternative fuels website
(www.afdc.energy.gov/afdc/locator/stations/) that
can help you find E85 fuel. Those stations that do have
E85 should have a label indicating ethanol content.
Do not use the fuel if the ethanol content is greater
than 85%.
At a minimum, E85 should meet ASTM Specification
D 5798. By definition, this means that fuel labeled E85
will have an ethanol content between 70% and 85%.
Filling the fuel tank with fuel mixtures that do not meet
ASTM specifications can affect driveability and could
cause the malfunction indicator lamp to come on.
To ensure quick starts in the wintertime, the E85 fuel
must be formulated properly for your climate according
to ASTM specification D 5798. If you have trouble
starting on E85, it could be because the E85 fuel is not
properly formulated for your climate. If this happens,
switching to gasoline or adding gasoline to the fuel
tank can improve starting. For good starting and heater
efficiency below 0°C (32°F), the fuel mix in the fuel tank
should contain no more than 70% ethanol. It is best
not to alternate repeatedly between gasoline and E85.If you do switch fuels, it is recommended that you add
as much fuel as possible
—do not add less than 11 L
(3 gal) when refueling. You should drive the vehicle
immediately after refueling for at least 11 km (7 mi) to
allow the vehicle to adapt to the change in ethanol
concentration.
E85 has less energy per liter (gallon) than gasoline, so
you will need to refill the fuel tank more often when
using E85 than when you are using gasoline. See
Filling the Tank on page 6‑9.
Notice: Some additives are not compatible with
E85 fuel and can harm the vehicle's fuel system.
Do not add anything to E85. Damage caused by
additives would not be covered by the vehicle
warranty.
Notice: This vehicle was not designed for fuel that
contains methanol. Do not use fuel containing
methanol. It can corrode metal parts in the fuel
system and also damage plastic and rubber parts.
That damage would not be covered under the
vehicle warranty.
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Black plate (19,1)Buick Lucerne Owner Manual - 2011
When to Add Engine Oil
3.9L V6 Engine
4.6L V8 Engine
If the oil is below the cross-hatched area at the tip of
the dipstick, add 1 L (1 qt) of the recommended oil
and then recheck the level. See “Selecting the Right
Engine Oil” in this section for an explanation of what
kind of oil to use. For engine oil crankcase capacity, see
Capacities and Specifications on page 6‑116. Notice:
Do not add too much oil. Oil levels above or
below the acceptable operating range shown on the
dipstick are harmful to the engine. If you find that
you have an oil level above the operating range, i.e.,
the engine has so much oil that the oil level gets
above the cross-hatched area that shows the proper
operating range, the engine could be damaged. You
should drain out the excess oil or limit driving of the
vehicle and seek a service professional to remove
the excess amount of oil.
See Engine Compartment
Overviewon page 6‑14for the location of the
engine oil fill cap.
Add enough oil to put the level somewhere in the proper
operating range. Push the dipstick all the way back in
when through.
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Black plate (20,1)Buick Lucerne Owner Manual - 2011
Selecting the Right Engine Oil
Selecting the right engine oil depends on both the
proper oil specification and viscosity grade:
Specification
Use and ask for engine oils with the dexos™
certification mark. Oils meeting the requirements of the
vehicle should have the dexos certification mark on the
container. This certification mark indicates that the oil
has been approved to the dexos specification.
This vehicle was filled at the factory with
dexos‐approved engine oil.Notice:
Use only engine oil that is approved to
the dexos specification or an equivalent engine
oil of the appropriate viscosity grade. Engine oils
approved to the dexos specification will show the
dexos symbol on the container. Failure to use the
recommended engine oil or equivalent can result in
engine damage not covered by the vehicle warranty.
If you are unsure whether the oil is approved to the
dexos specification, ask your service provider.
Use of Substitute Engine Oils if dexos is unavailable:
In the event that dexos‐approved engine oil is not
available at an oil change or for maintaining proper
oil level, you may use substitute engine oil displaying
the API Starburst symbol and of SAE 5W-30 viscosity
grade. Use of oils that do not meet the dexos
specification, however, may result in reduced
performance under certain circumstances.
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Black plate (22,1)Buick Lucerne Owner Manual - 2011
Engine Oil Life System
When to Change Engine Oil
This vehicle has a computer system that indicates when
to change the engine oil and filter. This is based on
engine revolutions and engine temperature, and not on
mileage. Based on driving conditions, the mileage at
which an oil change is indicated can vary considerably.
For the oil life system to work properly, the system must
be reset every time the oil is changed.
When the system has calculated that oil life has been
diminished, it indicates that an oil change is necessary.
A CHANGE ENGINE OIL SOON message comes on.
SeeDIC Warnings and Messages
on page 4‑49.
Change the oil as soon as possible within the next
600 miles (1 000 km). It is possible that, if driving under
the best conditions, the oil life system might indicate
that an oil change is not necessary for up to a year. The
engine oil and filter must be changed at least once a
year and, at this time, the system must be reset. Your
dealer has trained service people who will perform this
work and reset the system. It is also important to check
the oil regularly over the course of an oil drain interval
and keep it at the proper level. If the system is ever reset accidentally, the oil must be
changed at 3,000 miles (5 000 km) since the last oil
change. Remember to reset the oil life system
whenever the oil is changed.
How to Reset the Engine Oil Life
System
Reset the system whenever the engine oil is changed
so that the system can calculate the next engine oil
change. Always reset the engine oil life to 100% after
every oil change. It will not reset itself. To reset the
system:
1. Display the OIL LIFE REMAINING on the DIC.
2. Press and hold the SET/RESET button on the DIC for more than five seconds. The oil life will change
to 100%.
If the CHANGE ENGINE OIL SOON message comes
back on when the vehicle is started, the engine oil life
system has not been reset. Repeat the procedure.
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Black plate (24,1)Buick Lucerne Owner Manual - 2011
To reinstall the cover:1. Align the two hinges located on the inboard side of the cover.
2. Push the cover slightly down and towards the engine to engage the tabs in the hinges and align
the two screws.
3. Tighten the two screws on the top of the engine air cleaner/filter cover.
{WARNING:
Operating the engine with the air cleaner/filter off
can cause you or others to be burned. The air
cleaner not only cleans the air; it helps to stop
flames if the engine backfires. Use caution when
working on the engine and do not drive with the
air cleaner/filter off.
Notice: If the air cleaner/filter is off, dirt can easily
get into the engine, which could damage it. Always
have the air cleaner/filter in place when you are
driving.
Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
A good time to check the automatic transmission fluid
level is when the engine oil is changed.
Change the fluid and filter at the intervals listed in
Scheduled Maintenance
on page 7‑3and be sure
to use the transmission fluid listed in Recommended
Fluids and Lubricants on page 7‑8.
How to Check Automatic Transmission
Fluid (3.9L Engine)
Because this operation can be a little difficult, you
may choose to have this done at the dealer 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 fluid can damage
the transmission. Too much can mean that some
of the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire. Too
little fluid could cause the transmission to overheat.
Be sure to get an accurate reading if checking the
transmission fluid.
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Black plate (27,1)Buick Lucerne Owner Manual - 2011
3. After adding fluid, recheck the fluid level asdescribed under “How to Check Automatic
Transmission Fluid” earlier in this section.
4. When the correct fluid level is obtained, push the dipstick back in all the way.
How to Check Automatic Transmission
Fluid (4.6L Engine)
For the 4.6L V8 engine, it is not necessary to check
the transmission fluid level. A transmission fluid leak is
the only reason for fluid loss. If a leak occurs, take the
vehicle to your dealer service department and have it
repaired as soon as possible.
Cooling System
The cooling system allows the engine to maintain the
correct working temperature.
3.9L Engine
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Electric Engine Cooling Fans
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Black plate (29,1)Buick Lucerne Owner Manual - 2011
The following explains the cooling system and how
to check and add coolant when it is low. If there is a
problem with engine overheating, seeEngine
Overheating on page 6‑35.
What to Use
{WARNING:
Adding only plain water or some other liquid to
the cooling system can be dangerous. Plain water
and other liquids, can boil before the proper
coolant mixture will. The coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could
get too hot but you would not get the overheat
warning. The engine could catch fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL coolant.
Use a 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant. If using this mixture, nothing else
needs to be added. This mixture:
.Gives freezing protection down to −34°F (−37°C),
outside temperature.
.Gives boiling protection up to 265°F (129°C),
engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are used
in the vehicle's cooling system, the vehicle could be
damaged. Use only the proper mixture of the engine
coolant listed in this manual for the cooling system.
See Recommended Fluids and Lubricants
on
page 7‑8for more information.
Never dispose of engine coolant by putting it in
the trash, pouring it on the ground, or into sewers,
streams or bodies of water. Have the coolant changed
by an authorized service center, familiar with legal
requirements regarding used coolant disposal. This will
help protect the environment and your health.
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Black plate (32,1)Buick Lucerne Owner Manual - 2011
What to Use
{WARNING:
Adding only plain water or some other liquid to the
cooling system can be dangerous. Plain water
and other liquids, can boil before the proper
coolant mixture will. The coolant warning system
is set for the proper coolant mixture. With plain
water or the wrong mixture, the engine could
get too hot but you would not get the overheat
warning. The engine could catch fire and you or
others could be burned. Use a 50/50 mixture of
clean, drinkable water and DEX-COOL coolant.
Use a 50/50 mixture of clean, drinkable water and
DEX-COOL coolant. If using this mixture, nothing else
needs to be added. This mixture:
.Gives freezing protection down to −34°F (−37°C),
outside temperature.
.Gives boiling protection up to 265°F (129°C),
engine temperature.
.Protects against rust and corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine temperature.
Notice: If an improper coolant mixture is used, the
engine could overheat and be badly damaged. The
repair cost would not be covered by the vehicle
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core, and
other parts.
Notice: If extra inhibitors and/or additives are
used in the vehicle's cooling system, the vehicle
could be damaged. Use only the proper mixture
of the engine coolant listed in this manual for the
cooling system. See Recommended Fluids and
Lubricants
on page 7‑8for more information.
Never dispose of engine coolant by putting it in
the trash, pouring it on the ground, or into sewers,
streams or bodies of water. Have the coolant changed
by an authorized service center, familiar with legal
requirements regarding used coolant disposal. This will
help protect the environment and your health.
6-32