
Black plate (26,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-26 Vehicle Care
Replacing Brake System Parts
Always replace brake system parts
with new, approved replacement
parts. If this is not done, the brakes
may not work properly. The braking
performance expected can change
in many other ways if the wrong
replacement brake parts are
installed or parts are improperly
installed.
Brake Fluid
The brake master cylinder reservoir
is filled with DOT 3 brake fluid as
indicated on the reservoir cap. See
Engine Compartment Overview on
page 10-6for the location of the
reservoir. There are only two reasons why the
brake fluid level in the reservoir
might go down:
.The brake fluid level goes down
because of normal brake lining
wear. When new linings are
installed, the fluid level goes
back up.
.A fluid leak in the brake
hydraulic system can also cause
a low fluid level. Have the brake
hydraulic system fixed, since a
leak means that sooner or later
the brakes will not work well.
Do not top off the brake fluid.
Adding fluid does not correct a leak.
If fluid is added when the linings are
worn, there will be too much fluid
when new brake linings are
installed. Add or remove brake fluid,
as necessary, only when work is
done on the brake hydraulic system.
{Warning
If too much brake fluid 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 fluid only when work is
done on the brake hydraulic
system.
When the brake fluid falls to a low
level, the brake warning light comes
on. See Brake System Warning
Light on page 5-19.
What to Add
Use only new DOT 3 brake fluid
from a sealed container. See
Recommended Fluids and
Lubricants on page 11-12.
Always clean the brake fluid
reservoir cap and the area around
the cap before removing it. This
helps keep dirt from entering the
reservoir.

Black plate (27,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-27
{Warning
With the wrong kind of fluid in the
brake hydraulic system, the
brakes might not work well. This
could cause a crash. Always use
the proper brake fluid.
{Caution
.Using the wrong fluid 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 fluid.(Continued)
Caution (Continued)
.If brake fluid is spilled on the
vehicle's painted surfaces,
the paint finish can be
damaged. Be careful not to
spill brake fluid on the
vehicle. If you do, wash it off
immediately.
Battery
The original equipment battery is
maintenance free. Do not remove
the cap and do not add fluid.
This vehicle has a standard 12-volt
battery. Refer to the replacement
number on the original battery label
when a new standard 12-volt battery
is needed.
eAssist vehicles also have a high
voltage battery. Only a trained
service technician with the proper
knowledge and tools should inspect,
test, or replace the high voltage
battery. See your dealer if the high
voltage battery needs service. The dealer has information on how to
recycle the high voltage battery.
There is also information available
at http://www.recyclemybattery.com.
The eAssist system high voltage
battery is cooled with air drawn from
the vehicle interior. The cold air
intake for the battery is behind the
rear seat, on the filler panel. Do not
cover the intake.

Black plate (28,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-28 Vehicle Care
{Warning
Battery posts, terminals, and
related accessories contain lead
and lead compounds, chemicals
known to the State of California to
cause cancer and reproductive
harm. Wash hands after handling.
Vehicle Storage
{Warning
Batteries have acid that can burn
you and gas that can explode.
You can be badly hurt if you are
not careful. SeeJump Starting
(On-board with eAssist Only) on
page 10-78 orJump Starting (with
or without eAssist) on page 10-79
for tips on working around a
battery without getting hurt. Infrequent Usage: Remove the
12-volt battery black, negative (−)
cable from the battery to keep the
battery from running down.
Extended Storage: Remove the
12-volt battery black, negative (−)
cable from the battery or use a
battery trickle charger.
Remember to reconnect the battery
when ready to drive the vehicle.
All-Wheel Drive
Transfer Case
Under normal driving conditions,
transfer case fluid does not require
changing or checking unless there
is a fluid leak or unusual noise.
If required, have the transfer case
serviced by your dealer.
Starter Switch Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle.
2. Apply both the parking brake and the regular brake.
Do not use the accelerator
pedal, and be ready to turn off
the engine immediately if it
starts.
3. Try to start the engine in each gear. The vehicle should start
only in P (Park) or N (Neutral).
If the vehicle starts in any other
position, contact your dealer for
service.

Black plate (29,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-29
Automatic Transmission
Shift Lock Control
Function Check
{Warning
When you are doing this
inspection, the vehicle could
move suddenly. If the vehicle
moves, you or others could be
injured.
1. Before starting this check, be sure there is enough room
around the vehicle. It should be
parked on a level surface.
2. Apply the parking brake. Be ready to apply the regular brake
immediately if the vehicle begins
to move. 3. With the engine off, turn the
ignition on, but do not start the
engine. Without applying the
regular brake, try to move the
shift lever out of P (Park) with
normal effort. If the shift lever
moves out of P (Park), contact
your dealer for service.
Ignition Transmission
Lock Check
If equipped with a key type ignition,
while parked and with the parking
brake set, try to turn the ignition to
LOCK/OFF in each shift lever
position.
.The ignition should turn to
LOCK/OFF only when the shift
lever is in P (Park).
.The ignition key should come
out only in LOCK/OFF.
Contact your dealer if service is
required.
Park Brake and P (Park)
Mechanism Check
{Warning
When you are doing this check,
the vehicle could begin to move.
You or others could be injured
and property could be damaged.
Make sure there is room in front
of the vehicle in case it begins to
roll. Be ready to apply the regular
brake at once should the vehicle
begin to move.
Park on a fairly steep hill, with the
vehicle facing downhill. Keeping
your foot on the regular brake, set
the parking brake.
.To check the parking brake's
holding ability: With the engine
running and the transmission in
N (Neutral), slowly remove foot
pressure from the regular brake
pedal. Do this until the vehicle is
held by the parking brake only.

Black plate (31,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-31
Headlamp Aiming
Headlamp aim has been preset and
should need no further adjustment.
If the vehicle is damaged in a crash,
the headlamp aim may be affected.
If adjustment to the headlamps is
necessary, see your dealer.
Bulb Replacement
For the proper type of replacement
bulbs, seeReplacement Bulbs on
page 10-34.
For any bulb changing procedure
not listed in this section, contact
your dealer.
Halogen Bulbs
{Warning
Halogen bulbs have pressurized
gas inside and can burst if you
drop or scratch the bulb. You or
others could be injured. Be sure
to read and follow the instructions
on the bulb package.
High Intensity Discharge
(HID) Lighting
{Warning
The high intensity discharge
lighting system operates at a very
high voltage. If you try to service
any of the system components,
you could be seriously injured.
Have your dealer or a qualified
technician service them.
After an HID headlamp bulb has
been replaced, the beam might be a
slightly different shade than it was
originally. This is normal.
LED Lighting
This vehicle has several LED lamps.
For replacement of any LED lighting
assembly, contact your dealer.

Black plate (34,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-34 Vehicle Care
3. Turn the bulb socket (1)counterclockwise to remove it
from the lamp assembly (3).
4. Pull the bulb (2) straight out of the bulb socket.
5. Push the replacement bulb straight into the bulb socket and
turn the bulb socket clockwise to
install it into the lamp assembly.
6. Move the lamp assembly into the trunk lid, engaging the clip
side first.
7. Push on the lamp side opposite the clip until the lamp assembly
snaps into place.
Replacement Bulbs
Exterior Lamp Bulb
Number
Back-Up Lamp 921LL (W16W)
Front Turn
Signal Lamp 7444NA
Headlamp High
Beam (Base) HIR2
Headlamp Low
Beam (Base) HIR2
License Plate Lamp W5WLL
Rear Turn Signal 7443NA (WY21W)
For replacement bulbs not listed
here, contact your dealer.
Electrical System
High Voltage Devices and
Wiring
{Warning
Exposure to high voltage can
cause shock, burns, and even
death. The high voltage
components in the vehicle can
only be serviced by technicians
with special training.
High voltage components are
identified by labels. Do not
remove, open, take apart,
or modify these components.
High voltage cable or wiring has
orange covering. Do not probe,
tamper with, cut, or modify high
voltage cable or wiring.

Black plate (42,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
10-42 Vehicle Care
Wheels and Tires
Tires
Every new GM vehicle has
high-quality tires made by a
leading tire manufacturer. See
the warranty manual for
information regarding the tire
warranty and where to get
service. For additional
information refer to the tire
manufacturer.
{Warning
.Poorly maintained and
improperly used tires are
dangerous.
.Overloading the tires can
cause overheating as a
result of too much flexing.
There could be a blowout
(Continued)
Warning (Continued)
and a serious crash. See
Vehicle Load Limits on
page 9-10.
.Underinflated tires pose
the same danger as
overloaded tires. The
resulting crash could
cause serious injury.
Check all tires frequently
to maintain the
recommended pressure.
Tire pressure should be
checked when the tires
are cold.
.Overinflated tires are more
likely to be cut, punctured,
or broken by a sudden
impact —such as when
hitting a pothole. Keep
tires at the recommended
pressure.
(Continued)
Warning (Continued)
.Worn or old tires can
cause a crash. If the tread
is badly worn,
replace them.
.Replace any tires that
have been damaged by
impacts with potholes,
curbs, etc.
.Improperly repaired tires
can cause a crash. Only
the dealer or an
authorized tire service
center should repair,
replace, dismount, and
mount the tires.
.Do not spin the tires in
excess of 56 km/h
(35 mph) on slippery
surfaces such as snow,
mud, ice, etc. Excessive
spinning may cause the
tires to explode.

Black plate (51,1)Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada/Mexico-
7707475) - 2015 - CRC - 10/9/14
Vehicle Care 10-51
Remove the valve cap from the
tire valve stem. Press the tire
gauge firmly onto the valve to
get a pressure measurement.
If the cold tire inflation pressure
matches the recommended
pressure on the Tire and
Loading Information label, no
further adjustment is necessary.
If the inflation pressure is low,
add air until the recommended
pressure is reached. If the
inflation pressure is high, press
on the metal stem in the center
of the tire valve to release air.
Recheck the tire pressure with
the tire gauge.
Return the valve caps on the
valve stems to prevent leaks
and keep out dirt and moisture.Tire Pressure for
High-Speed Operation
{Warning
Driving at high speeds, 160 km/h
(100 mph) or higher, puts an
additional strain on tires.
Sustained high-speed driving
causes excessive heat buildup
and can cause sudden tire failure.
You could have a crash and you
or others could be killed. Some
high-speed rated tires require
inflation pressure adjustment for
high-speed operation. When
speed limits and road conditions
are such that a vehicle can be
driven at high speeds, make sure
the tires are rated for high-speed
operation, in excellent condition,
and set to the correct cold tire
inflation pressure for the
vehicle load.Vehicles with P245/45R19 size tires
require inflation pressure adjustment
when driving the vehicle at speeds
of 160 km/h (100 mph) or higher.
Set the cold inflation pressure to
248 kPa (36 psi).
Vehicles with P245/40R20 size tires
require inflation pressure adjustment
when driving the vehicle at speeds
of 160 km/h (100 mph) or higher.
Set the cold inflation pressure to
270 kPa (39 psi).
Return the tires to the
recommended cold tire inflation
pressure when high-speed driving
has ended. See
Vehicle Load Limits
on page 9-10 andTire Pressure on
page 10-50.
Tire Pressure Monitor
System
The Tire Pressure Monitor System
(TPMS) uses radio and sensor
technology to check tire pressure
levels. The TPMS sensors monitor