brake BUICK LACROSSE 2009 Service Manual

Turn Signals When Towing a Trailer
The arrows on the instrument panel ash whenever
signaling a turn or lane change. Properly hooked up, the
trailer lamps also ash, telling other drivers the vehicle
is turning, changing lanes or stopping.
When towing a trailer, the arrows on the instrument
panel ash for turns even if the bulbs on the trailer are
burned out. For this reason you may think other
drivers are seeing the signal when they are not. It is
important to check occasionally to be sure the
trailer bulbs are still working.
Driving on Grades
Notice:Do not tow on steep continuous grades
exceeding 6 miles (9.6 km). Extended, higher than
normal engine and transmission temperatures may
result and damage the vehicle. Frequent stops are
very important to allow the engine and transmission
to cool.
Reduce speed and shift to a lower gearbeforestarting
down a long or steep downgrade. If the transmission 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 the engine and the transmission
overheating. If the engine does overheat, seeEngine
Overheating on page 5-31.
Parking on Hills
{CAUTION:
Parking the vehicle on a hill with the trailer
attached can be dangerous. If something goes
wrong, the rig could start to move. People can be
injured, and both the vehicle and the trailer can be
damaged. When possible, always park the rig on a
at surface.
If parking the rig on a hill:
1. Press the brake pedal, but do not shift into P (Park)
yet. Turn the wheels into the curb if facing downhill
or into traffic if facing uphill.
2. Have someone place chocks under the trailer
wheels.
3. When the wheel chocks are in place, release the
brake pedal until the chocks absorb the load.
4. Reapply the brake pedal. Then apply the parking
brake and shift the transmission into P (Park).
5. Release the brake pedal.
4-33

Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
start the engine,
shift into a gear, and
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 needs service more often when pulling a
trailer. SeeScheduled Maintenance on page 6-4
for more information. Things that are especially
important in trailer operation are automatic transmission
uid, engine oil, belts, cooling system and brake
system. It is a good idea to inspect these before and
during the 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 5-31.
Changing a Tire When Trailer Towing
If the vehicle gets a at tire while towing a trailer,
be sure to secure the trailer and disconnect it from the
vehicle before changing the tire.
4-34

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
the 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.........................5-22
Cooling System............................................5-24
Engine Coolant.............................................5-25
Radiator Pressure Cap..................................5-31Pressure Cap...............................................5-31
Engine Overheating.......................................5-31
Overheated Engine Protection
Operating Mode........................................5-34
Power Steering Fluid.....................................5-34
Windshield Washer Fluid................................5-35
Brakes........................................................5-37
Battery........................................................5-40
Jump Starting...............................................5-41
Headlamp Aiming..........................................
.5-46
Bulb Replacement..........................................5-49
Halogen Bulbs..............................................5-49
Taillamps, Turn Signal, Sidemarker,
Stoplamps and Back-up Lamps...................5-50
License Plate Lamp......................................5-52
Replacement Bulbs.......................................5-52
Windshield Replacement.................................5-53
Windshield Wiper Blade Replacement..............5-53
Tires..............................................................5-54
Tire Sidewall Labeling...................................5-55
Tire Terminology and Denitions.....................5-58
Ination - Tire Pressure.................................5-61
Tire Pressure Monitor System.........................5-62
Tire Pressure Monitor Operation.....................5-64
Tire Inspection and Rotation...........................5-67
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 the vehicle, they can affect vehicle 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 the vehicle warranty.
Damage to vehicle components resulting from the
installation or use of non-GM certied parts, including
control module modications, are not covered under the
terms of the vehicle warranty and may affect remaining
warranty coverage for affected parts.
GM Accessories are designed to complement and
function with other systems on the vehicle. Your GM
dealer/retailer can accessorize the 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 1-67.
5-3

Filling a Portable Fuel Container
{CAUTION:
Never ll a portable fuel container while it is in
the vehicle. Static electricity discharge from the
container can ignite the fuel vapor. You can be
badly burned and the vehicle damaged if this
occurs. To help avoid injury to you and others:
Dispense fuel 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 fuel.
Do not use a cellular phone while
pumping fuel.
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 on page 5-40.
C. Remote Positive (+) Terminal. SeeJump Starting on
page 5-41.
D.Passenger Compartment Air Filter on page 3-29.
E.Underhood Fuse Block on page 5-101.
F. Engine Coolant Recovery Tank. SeeCooling System
on page 5-24.
G.Radiator Pressure Cap on page 5-31.
H. Power Steering Fluid Reservoir (Out of View).
SeePower Steering Fluid on page 5-34.
I. Electric Engine Cooling Fans. SeeCooling System
on page 5-24.J. Engine Oil Dipstick. See “Checking Engine Oil”
underEngine Oil on page 5-15.
K. Engine Oil Fill Cap. See “When to Add Engine Oil”
underEngine Oil on page 5-15.
L. Automatic Transmission Fluid Dipstick.
See “Checking the Fluid Level” underAutomatic
Transmission Fluid on page 5-22.
M. Engine Coolant Bleed Valve. See “How to Add
Coolant to the Radiator” underCooling System on
page 5-24.
N. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-37.
O.Engine Air Cleaner/Filter on page 5-20.
5-13

A. Windshield Washer Fluid Reservoir. See “Adding
Washer Fluid” underWindshield Washer Fluid
on page 5-35.
B.Battery on page 5-40.
C. Underhood Fuse Block. SeeUnderhood Fuse Block
on page 5-101.
D. Remote Positive (+) Terminal. SeeJump Starting on
page 5-41.
E.Passenger Compartment Air Filter on page 3-29.
F. Pressure Cap. SeePressure Cap on page 5-31.
G. Power Steering Fluid Reservoir. SeePower Steering
Fluid on page 5-34.
H. Engine Oil Dipstick. 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 5-22.
K. Brake Master Cylinder Reservoir. See “Brake Fluid”
underBrakes on page 5-37.
L.Engine Air Cleaner/Filter on page 5-20.
M. Engine Coolant Recovery Tank. SeeCooling System
on page 5-24.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.
SeeEngine Compartment Overview on page 5-12
for 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

Automatic Transmission Fluid
When to Check and Change Automatic
Transmission Fluid
A good time to check the automatic transmission uid
level is when the engine oil is changed.
Change the uid and lter at the intervals listed in
Additional Required Services on page 6-6, and be sure
to use the transmission uid listed inRecommended
Fluids and Lubricants on page 6-11.
How to Check Automatic Transmission
Fluid
Because this operation can be a little difficult, you may
choose to have this done at the dealer/retailer 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
your transmission. Too much can mean that some
of the uid could come out and fall on hot engine
parts or exhaust system parts, starting a re.
Too little uid could cause the transmission to
overheat. Be sure to get an accurate reading if
you check your transmission uid.Wait at least 30 minutes before checking the
transmission 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:
1. Park the vehicle on a level place. Keep the engine
running.
2. With the parking brake applied, place the shift lever
in P (Park).
3. With your foot on the brake pedal, move the
shift lever through each gear, pausing for about
three seconds in each one. Then, position the shift
lever in P (Park).
4. Let the engine run at idle for three to ve minutes.
5-22

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 brake uid level goes down because of normal
brake lining wear. When new linings are installed,
the uid level goes back up.
A uid leak in the brake hydraulic system can also
cause a low uid level. Have the brake hydraulic
system xed, since a leak means that sooner
or later the brakes will not work well.Do not top off the brake uid. Adding uid does 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 too much brake uid is added, it can spill on the
engine and burn, if the engine is hot enough. You
or others could be burned, and the 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 3-35.
5-37

What to Add
Use only new DOT-3 brake uid from a sealed
container. SeeRecommended Fluids and Lubricants
on page 6-11.
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 brake uid is spilled on the vehicle’s painted
surfaces, the paint nish can be damaged.
Be careful not to spill brake uid on the vehicle.
If you do, wash it off immediately. SeeWashing
Your Vehicle on page 5-93.
5-38