Brakes BUICK LUCERNE 2008 Owner's Guide

Before you start, check all trailer hitch parts 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 will need more passing distance up ahead when
you are towing a trailer. And, because the vehicle
is a good deal longer, you will 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.
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 are turning with a trailer, make wider turns
than normal. Do this so your trailer will not 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/retailer. 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 are about to turn,
change lanes or stop.
4-30

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
is 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 are 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 gearbeforeyou start
down a long or steep downgrade. If you do not 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 to THIRD (3) and
reduce your speed to around 45 mph (70 km/h) to
reduce the possibility of engine and transmission
overheating.
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 is
how to do it:
1. Apply your regular brakes, but do not 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.
4-31

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.
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
Your vehicle will need service more often when you’re
pulling a trailer. See the Maintenance Schedule for more
on this. Things that are especially important in trailer
operation are automatic transmission uid (don’t overll),
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 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 5-28.
4-32

Service............................................................5-3
Accessories and Modications..........................5-3
California Proposition 65 Warning.....................5-4
California Perchlorate Materials Requirements.....5-4
Doing Your Own Service Work.........................5-4
Adding Equipment to the Outside of Your
Vehicle......................................................5-5
Fuel................................................................5-5
Gasoline Octane............................................5-6
Gasoline Specications....................................5-6
California Fuel...............................................5-6
Additives.......................................................5-7
Fuels in Foreign Countries...............................5-7
Filling the Tank..............................................5-8
Filling a Portable Fuel Container.....................5-10
Checking Things Under the Hood....................5-10
Hood Release..............................................5-11
Engine Compartment Overview.......................5-12
Engine Oil...................................................5-15
Engine Oil Life System..................................5-18
Engine Air Cleaner/Filter................................5-20
Automatic Transmission Fluid.........................5-21
Engine Coolant.............................................5-24
Radiator Pressure Cap..................................5-28
Coolant Surge Tank Pressure Cap..................5-28
Engine Overheating.......................................5-28Overheated Engine Protection
Operating Mode........................................5-30
Cooling System (3.8L V6 Engine)....................5-30
Cooling System (4.6L V8 Engine)....................5-36
Power Steering Fluid.....................................5-40
Windshield Washer Fluid................................5-41
Brakes........................................................5-42
Battery........................................................5-46
Jump Starting...............................................5-48
Headlamp Aiming...........................................5-53
Bulb Replacement..........................................5-56
Halogen Bulbs..............................................5-56
Taillamps, Turn Signal, Stoplamps and
Sidemarker Lamps.....................................5-56
Taillamps and Back-Up Lamps.......................5-57
License Plate Lamp......................................5-58
Replacement Bulbs.......................................5-59
Windshield Wiper Blade Replacement..............5-59
Tires..............................................................5-60
Tire Sidewall Labeling...................................5-61
Tire Terminology and Denitions.....................5-64
Ination - Tire Pressure.................................5-67
Tire Pressure Monitor System.........................5-69
Tire Pressure Monitor Operation.....................5-70
Tire Inspection and Rotation...........................5-74
Section 5 Service and Appearance Care
5-1

Service
For service and parts needs, visit your dealer/retailer.
You will receive genuine GM parts and GM-trained and
supported service people.
Genuine GM parts have one of these marks:
Accessories and Modications
When non-dealer/non-retailer accessories are added to
your vehicle they can affect your vehicle’s performance
and safety, including such things as, airbags, braking,
stability, ride and handling, emissions systems,
aerodynamics, durability, and electronic systems like
antilock brakes, traction control and stability control.
Some of these accessories could even cause
malfunction or damage not covered by warranty.
GM Accessories are designed to complement and
function with other systems on your vehicle. Your GM
dealer/retailer can accessorize your vehicle using
genuine GM Accessories. When you go to your GM
dealer/retailer and ask for GM Accessories, you
will know that GM-trained and supported service
technicians will perform the work using genuine GM
Accessories.
Also, seeAdding Equipment to Your Airbag-Equipped
Vehicle on page 1-72.
5-3

A. Radiator Pressure Cap. SeeRadiator Pressure Cap
on page 5-28.
B. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-41.
C. Remote Positive (+) Battery Terminal. SeeJump
Starting on page 5-48.
D. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-106.
E. Engine Coolant Recovery Tank. See Index.
F. Power Steering Fluid Reservoir (Out of View). See
Power Steering Fluid on page 5-40.
G. Electric Engine Cooling Fans. See Index.H. Engine Oil Dipstick (Out of View). See “Checking
Engine Oil” underEngine Oil on page 5-15.
I. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
J. Automatic Transmission Fluid Dipstick. See
“Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-21.
K. Brake Fluid Reservoir. See “Brake Fluid” under
Brakes on page 5-42.
L. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.
5-13

A. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-106.
B. Remote Positive (+) Terminal. SeeJump Starting on
page 5-48.
C. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-41.
D. Engine Coolant Surge Tank and Pressure Cap See
Coolant Surge Tank Pressure Cap on page 5-28
andCooling System (3.8L V6 Engine) on page 5-30
orCooling System (4.6L V8 Engine) on page 5-36.
E. Remote Negative (−) Terminal. SeeJump Starting on
page 5-48.
F. Power Steering Fluid. SeePower Steering Fluid on
page 5-40.
G. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
H. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
I. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-42.
J. Automatic Transmission Fluid Cap and Dipstick (Out
of View). SeeAutomatic Transmission Fluid on
page 5-21.
K. Engine Air Cleaner/Filter. SeeEngine Air
Cleaner/Filter on page 5-20.Engine Oil
Checking Engine Oil
It is a good idea to check the 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.
1. Turn off the engine and give the oil several minutes
to drain back into the oil pan. If you do not do this,
the oil dipstick might not show the actual level.
2. 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.
5-15

Brakes
Brake Fluid
The brake master cylinder
reservoir is lled with
DOT-3 brake uid. See
Engine 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 during
normal 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 hydraulic system. If
it is, you should have the brake hydraulic system
xed, since a leak means that sooner or later the brakes
will not work well.It is not a good idea to top off the brake uid. Adding
brake uid will not correct a leak. If uid is added when
the linings are worn, there will be too much uid
when new brake linings are installed. Add or remove
brake uid, as necessary, only when work is done on the
brake hydraulic system.
{CAUTION:
If your vehicle has 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.
When the brake uid falls to a low level, the brake
warning light comes on. SeeBrake System Warning
Light on page 3-39.
5-42

What to Add
When you 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 helps keep
dirt from entering the reservoir.
{CAUTION:
With the wrong kind of uid in the brake
hydraulic system, the brakes might not work
well. This could cause a crash. Always use the
proper brake uid.Notice:
Using the wrong uid can badly damage brake
hydraulic system parts. For example, just a
few drops of mineral-based oil, such as engine
oil, in the brake hydraulic system can damage
brake hydraulic 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. SeeWashing
Your Vehicle on page 5-98.
5-43

Brake Wear
Your vehicle has disc brakes. Disc brake pads have
built-in wear indicators that make a high-pitched warning
sound when the brake pads are worn and new pads
are needed. The sound can come and go or be heard all
the time your vehicle is moving, except when you are
pushing on the brake pedal rmly.
{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That could
lead to an accident. When you hear the brake
wear warning sound, have your vehicle
serviced.Notice:Continuing to drive with worn-out brake
pads could result in costly brake repair.
Some driving conditions or climates can cause a brake
squeal when the brakes are rst applied or lightly
applied. This does not mean something is wrong with
the brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated, inspect
brake pads for wear and evenly tighten wheel nuts in
the proper sequence to torque specications in
Capacities and Specifications on page 5-113.
Brake linings should always be replaced as complete
axle sets.
5-44