service BUICK LUCERNE 2007 Repair Manual

California Proposition 65 Warning
Most motor vehicles, including this one, contain
and/or emit chemicals known to the State of
California to cause cancer and birth defects or other
reproductive harm. Engine exhaust, many parts and
systems (including some inside the vehicle), many
uids, and some component wear by-products
contain and/or emit these chemicals.
Doing Your Own Service Work
{CAUTION:
You can be injured and your vehicle could
be damaged if you try to do service work
on a vehicle without knowing enough
about it.
Be sure you have sufficient knowledge,
experience, the proper replacement
parts, and tools before you attempt any
vehicle maintenance task.
CAUTION: (Continued)
CAUTION: (Continued)

Be sure to use the proper nuts, bolts,
and other fasteners. English and
metric fasteners can be easily
confused. If you use the wrong
fasteners, parts can later break or fall
off. You could be hurt.
If you want to do some of your own service work,
you will want to use the proper service manual.
It tells you much more about how to service your
vehicle than this manual can. To order the
proper service manual, seeService Publications
Ordering Information on page 478.
Your vehicle has an airbag system. Before
attempting to do your own service work, see
Servicing Your Airbag-Equipped Vehicle on
page 86.
You should keep a record with all parts receipts
and list the mileage and the date of any service
work you perform. SeeMaintenance Record
on page 455.
326

Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your
vehicle can affect the airow around it. This may
cause wind noise and affect windshield washer
performance. Check with your dealer before
adding equipment to the outside of your vehicle.
Fuel
Use of the recommended fuel is an important part
of the proper maintenance of your vehicle. To
help keep your engine clean and maintain optimum
vehicle performance, GM recommends the use
of gasoline advertised as TOP TIER Detergent
Gasoline.
The 8th digit of your Vehicle Identication Number
(VIN) shows the code letter or number that
identies your engine. You will nd the VIN at the
top left of the instrument panel. SeeVehicle
Identication Number (VIN) on page 427.
Gasoline Octane
If your vehicle has the 3.8L V6 engine (VIN
Code 2), 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 4.6L V8 engine (VIN
Code Y), use premium unleaded gasoline with a
posted octane rating of 91 or higher. You may also
use regular unleaded gasoline rated at 87 octane
or higher, but your vehicle’s acceleration may
be slightly reduced, and you may notice a slight
audible knocking noise, commonly referred to
as spark knock. If the octane is less than 87, you
may notice a heavy knocking noise when you
drive. If this occurs, use a gasoline rated at
87 octane or higher as soon as possible.
Otherwise, you might damage your engine. If you
are using gasoline rated at 87 octane or higher
and you hear heavy knocking, your engine needs
service.
327

Gasolines containing oxygenates, such as ethers
and ethanol, and reformulated gasolines may
be available in your area. General Motors
recommends that you use these gasolines if they
comply with the specications described earlier.
However, E85 (85% ethanol) and other fuels
containing more than 10% ethanol must not be
used in vehicles that were not designed for
those fuels.
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 recommends against 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 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.
329

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 the engine at extremely low temperatures.
Engine Oil Additives
Do not add anything to the 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 ENGINE OIL SOON
message will come on. SeeDIC Warnings
and Messages on page 221. Change your oil as
soon as possible within the next 600 miles
(1 000 km). 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.
340

How to Reset the Engine Oil Life
System
The Engine 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 ENGINE
OIL SOON message being turned on, reset the
system.
Always reset the engine oil life to 100% after
every oil change. It will not reset itself. To reset
the Engine Oil Life System, do the following:
1. Display the OIL LIFE REMAINING on the DIC.
2. Press and hold the SET/RESET button on
the DIC for more than ve seconds. The oil
life will change to 100%.
If the CHANGE ENGINE OIL SOON message
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
used oil, ask your dealer, a service station, or a
local recycling center for help.
341

How to Check Automatic Transaxle
Fluid (3.8L Engine)
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 your vehicle as follows:
1. Park your vehicle on a level place. Keep the
engine running.
2. With the parking brake applied, place the shift
lever in PARK (P).
3. 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).
4. Let the engine run at idle for three to
ve minutes.
344

How to Add Automatic Transaxle Fluid
Refer to the Maintenance Schedule to determine
what kind of transaxle uid to use. See
Recommended Fluids and Lubricants on page 452.
If the uid level is low, add only enough of the
proper uid to bring the level into the
cross-hatched area on the dipstick.
1. Pull out the dipstick.
2. Using a long-neck funnel, add enough uid at
the dipstick hole to bring it to the proper level.
It does not take much uid, generally less
than one pint (0.5 L). Do not overll.
Notice:Use of the incorrect automatic
transaxle uid may damage your vehicle, and
the damages may not be covered by your
warranty. Always use the automatic transaxle
uid listed inRecommended Fluids and
Lubricants on page 452.3. After adding uid, recheck the uid level as
described under “How to Check Automatic
Transaxle Fluid,” earlier in this section.
4. When the correct uid level is obtained, push
the dipstick back in all the way.
How to Check Automatic Transaxle
Fluid (4.6L Engine)
For the 4.6L V8 engine, it is not necessary to check
the transaxle uid level. A transaxle uid leak is the
only reason for uid loss. If a leak occurs, take your
vehicle to the dealership service department and
have it repaired as soon as possible.
346

Engine Coolant
The cooling system in your vehicle is lled with
DEX-COOL®engine coolant. This coolant is
designed to remain in your vehicle for ve years or
150,000 miles (240 000 km), whichever occurs
rst, if you add only DEX-COOL
®extended
life coolant.
The following explains your cooling system and
how to add coolant when it is low. If you have
a problem with engine overheating, seeEngine
Overheating on page 351.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®coolant will:
Give freezing protection down to
−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant may require changing sooner, at
the rst maintenance service after each
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
347

If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL (N) while stopped. If it is safe to do
so, pull off the road, shift to PARK (P) or
NEUTRAL (N) and let the engine idle.
2. Turn on your heater to full hot at the highest
fan speed and open the windows as
necessary.
If you no longer have the overheat warning, you
can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not come
back on, you can drive normally.
If the warning continues and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, you can idle the
engine for three minutes while you are parked.
If you still have the warning,turn off the engine
and get everyone out of the vehicleuntil it
cools down.
You may decide not to lift the hood but to get
service help right away.Overheated Engine Protection
Operating Mode
If an overheated engine condition exists and the
message ENGINE OVERHEATED STOP ENGINE
is displayed, an overheat protection mode which
alternates ring groups of cylinders helps
prevent engine damage. In this mode, you will
notice a loss in power and engine performance.
This operating mode allows your vehicle to
be driven to a safe place in an emergency. Driving
extended miles (km) and/or towing a trailer in
the overheat protection mode should be avoided.
Notice:After driving in the overheated
engine protection operating mode, to avoid
engine damage, allow the engine to cool before
attempting any repair. The engine oil will be
severely degraded. Repair the cause of coolant
loss, change the oil and reset the oil life
system. SeeEngine Oil on page 337.
353

{CAUTION:
Heater and radiator hoses, and other
engine parts, can be very hot. Do not
touch them. If you do, you can be burned.
Do not run the engine if there is a leak. If
you run the engine, it could lose all
coolant. That could cause an engine re,
and you could be burned. Get any leak
xed before you drive the vehicle.
If there seems to be no leak, with the engine on,
check to see if the electric engine cooling fans
are running. If the engine is overheating, both fans
should be running. If they are not, your vehicle
needs service.Notice:Engine damage from running your
engine without coolant is not covered by your
warranty.
Notice:Using coolant other than DEX-COOL®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
355