
Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 185
To shift out of D (Drive):1. Bring the vehicle to a complete stop.
2. Shift to the desired gear.
3. After releasing the shift lever, it will return to the center
position.
Downshifting the transmission in
slippery road conditions could result
in skidding. See “Skidding”under
Loss of Control 0163.
Caution
Spinning the tires or holding the
vehicle in one place on a hill
using only the accelerator pedal
may damage the transmission.
The repair will not be covered by
the vehicle warranty. If the vehicle
is stuck, do not spin the tires.
When stopping on a hill, use the
brakes to hold the vehicle in
place.
Caution
A transmission hot message may
display if the automatic
transmission fluid is too hot.
Driving under this condition can
damage the vehicle. Stop and idle
the engine to cool the automatic
transmission fluid. This message
clears when the transmission fluid
has cooled sufficiently.
SERVICE SHIFTER SEE
OWNER’S MANUAL Message
When this message displays in the
Driver Information Center (DIC), the
shift lever needs service. Have the
vehicle serviced as soon as
possible. If the vehicle is
automatically shifting into P (Park),
check to see if the P (Park) button
on top of the shifter is stuck. To
operate the vehicle, hold the shift
lever in the desired gear,
R (Reverse) or D (Drive), until
vehicle speed exceeds 15 km/h
(10 mph), then release the shift
lever.
Manual Mode
Tap Shift Caution
Driving with the engine at a high
rpm without upshifting while using
Tap Shift, could damage the
vehicle. Always upshift when
necessary while using Tap Shift.
Vehicles with Tap Shift have
controls on the back of the steering
wheel to manually shift the
automatic transmission.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
186 Driving and Operating
To enter Permanent Tap Shift Mode:1. With the transmission in D (Drive), pull back on the shift
lever to activate M (Manual
Mode). The M in the shift
pattern will illuminate in red,
and the D will switch to white.
2. Tap the left steering wheel control to downshift, and the
right control to upshift. To shift
to the lowest available gear,
press and hold the left control.
3. To exit, pull back on the shift lever a second time. The D in
the shift pattern will illuminate
in red, and the M will switch to
white.
To enter Temporary Tap Shift Mode: 1. With transmission in D, Tap the left steering wheel control to
downshift, and the right control
to upshift. 2. To shift to the lowest available
gear, press and hold the left
control.
3. To deactivate, hold the right upshift control briefly.
After temporary tap shifts, automatic
shifts return after no manual shifts
have been done for seven to
10 seconds.
While using Tap Shift, the vehicle
will have firmer, quicker shifting.
This can be used for sport driving or
when climbing or descending hills,
to stay in gear longer, or to
downshift for more power or engine
braking.
The transmission will only allow
shifting into gears appropriate for
the vehicle speed and engine
revolutions per minute (rpm). The
transmission will not automatically
shift to the next lower gear if the
engine rpm is too high, nor to the
next higher gear when the maximum
engine rpm is reached. If shifting is prevented for any
reason, a SHIFT DENIED message
will be displayed in the instrument
cluster.
When accelerating the vehicle from
a stop in snowy and icy conditions,
it is suggested to shift into second
gear. A higher gear allows the
vehicle to gain more traction on
slippery surfaces.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 195
Passing Another Vehicle While
Using Cruise Control
Use the accelerator pedal to
increase the vehicle speed. When
you take your foot off the pedal, the
vehicle will slow down to the
previously set cruise speed. While
pressing the accelerator pedal or
shortly following the release to
override cruise control, briefly
pressing SET−will result in cruise
set to the current vehicle speed.
Using Cruise Control on Hills
How well the cruise control will work
on hills depends upon the vehicle
speed, load, and the steepness of
the hills. When going up steep hills,
you might have to step on the
accelerator pedal to maintain your
speed. When going downhill, you
might have to brake or shift to a
lower gear to keep your speed
down. If the brake pedal is applied,
cruise control will disengage.
Ending Cruise Control
There are four ways to end cruise
control:
. Step lightly on the brake pedal. .
Press*.
. Shift the transmission to
N (Neutral).
. To turn off cruise control,
press
5.
Erasing Speed Memory
The cruise control set speed is
erased from memory if
5is pressed
or the ignition is turned off.
Adaptive Cruise Control
If equipped with Adaptive Cruise
Control (ACC), it allows for selecting
the cruise control set speed and
following gap. Read this entire
section before using this system.
ACC uses a radar sensor to detect
other vehicles. See Radio
Frequency Statement 0335. The
following gap is the following time
(or distance) between your vehicle
and a vehicle detected directly
ahead in your path, moving in the
same direction. If no vehicle is
detected in your path, ACC works
like regular cruise control. If a vehicle is detected in your path,
ACC can speed up the vehicle or
apply limited, moderate braking to
maintain the selected following gap.
To disengage ACC, apply the brake.
If the Traction Control System (TCS)
or StabiliTrak
®electronic stability
control system activates while ACC
is engaged, ACC may automatically
disengage. See Traction Control/
Electronic Stability Control 0190.
When road conditions allow ACC to
be safely used, ACC can be turned
back on. ACC will not engage if the
TCS or StabiliTrak electronic
stability control system is disabled.
{Warning
ACC has limited braking ability
and may not have time to slow
the vehicle down enough to avoid
a collision with another vehicle
you are following. This can occur
when vehicles suddenly slow or
stop ahead, or enter your lane.
Also see “Alerting the Driver” in
this section. Complete attention is
(Continued)

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 221
Warning (Continued)
.Use approved fuel
containers.
. Remove the container from
the vehicle, trunk, or pickup
bed before filling.
. Place the container on the
ground.
. Place the nozzle inside the
fill opening of the container
before dispensing fuel, and
keep it in contact with the fill
opening until filling is
complete.
. Fill the container no more
than 95% full to allow for
expansion.
. Do not smoke, light
matches, or use lighters
while pumping fuel.
. Avoid using cell phones or
other electronic devices.
Trailer Towing
General Towing
Information
Only use towing equipment that has
been designed for the vehicle.
Contact your dealer or trailering
dealer for assistance with preparing
the vehicle for towing a trailer. Read
the entire section before towing a
trailer.
For towing a disabled vehicle, see
Towing the Vehicle 0297. For
towing the vehicle behind another
vehicle such as a motor home, see
Recreational Vehicle Towing 0298.
Driving Characteristics
and Towing Tips
Driving with a Trailer
When towing a trailer:
.
Become familiar with the state
and local laws that apply to
trailer towing. .
Do not tow a trailer during the
first 800 km (500 mi) to prevent
damage to the engine, axle,
or other parts.
. Then during the first 800 km
(500 mi) of trailer towing, do not
drive over 80 km/h (50 mph) and
do not make starts at full throttle.
. Vehicles can tow in D (Drive).
Shift the transmission to a lower
gear if the transmission shifts
too often under heavy loads and/
or hilly conditions.
. Do not use Adaptive Cruise
Control when towing.
. The Forward Automatic Braking
system should be set to Off
when towing. See Forward
Automatic Braking (FAB) 0210.
. Turn off Lane Keep Assist (LKA)
when towing.
. Turn off Parking Assist when
towing.
. Front Pedestrian Braking should
be on Off or Alert.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Driving and Operating 223
or other objects. Avoid jerky or
sudden maneuvers. Signal well in
advance.
If the trailer turn signal bulbs burn
out, the arrows on the instrument
cluster will still flash for turns. It is
important to check occasionally to
be sure the trailer bulbs are still
working.
Driving on Grades
Reduce speed and shift to a lower
gearbefore starting down a long or
steep downgrade. If the
transmission is not shifted down, the
brakes might get hot and no longer
work well.
Vehicles can tow in D (Drive). Shift
the transmission to a lower gear if
the transmission shifts too often
under heavy loads and/or hilly
conditions.
When towing at high altitude on
steep uphill grades, consider the
following: Engine coolant will boil at
a lower temperature than at normal
altitudes. If the engine is turned off
immediately after towing at high
altitude on steep uphill grades, the vehicle may show signs similar to
engine overheating. To avoid this,
let the engine run while parked,
preferably on level ground, with the
automatic transmission in P (Park)
for a few minutes before turning the
engine off. If the overheat warning
comes on, see
Engine Overheating
0 243.
Parking on Hills
{Warning
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 flat 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 regular
brakes until the chocks absorb
the load.
4. Reapply the brake pedal. Then apply the parking brake and
shift into P (Park).
5. Release the brake pedal.
Leaving After Parking on a Hill
1. Apply and hold the brake pedal.
2. Start the engine.
3. Shift into a gear.
4. Release the parking brake.
5. Let up on the brake pedal.
6. Drive slowly until the trailer is clear of the chocks.
7. Stop and have someone pick up and store the chocks.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
224 Driving and Operating
Maintenance when Trailer
Towing
The vehicle needs service more
often when pulling a trailer. See
Maintenance Schedule0311.
Things that are especially important
in trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, 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.
Trailer Towing
Before pulling a trailer, three
important considerations have to do
with weight:
. Weight of the trailer
. Weight of the trailer tongue
. Total weight on your vehicle's
tires
Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than
454 kg (1,000 lb). But even that can
be too heavy.
It depends on how the rig is used.
For example, speed, altitude, road
grades, outside temperature, the
dimensions of the front of the trailer,
and how much the vehicle is used
to pull a trailer are all important.
It can depend on any special
equipment on the vehicle, and the
amount of tongue weight the vehicle
can carry. See “Weight of the Trailer
Tongue” following.
Maximum trailer weight is calculated
assuming the tow vehicle has the
driver, a front seat passenger, all the
required tow equipment, and all the
required trailering equipment. The
weight of additional optional
equipment, passengers, and cargo
in the tow vehicle must be
subtracted from the maximum trailer
weight. Ask your dealer for trailering
information or advice, or write us at
our Customer Assistance Offices.
See
Customer Assistance Offices
0 327.
Weight of the Trailer Tongue
The tongue load (1) of any trailer is
an important weight to measure
because it affects the total gross
weight of the vehicle. The Gross
Vehicle Weight (GVW) includes the
curb weight of the vehicle, any
cargo carried in it, and the people
who will be riding in the vehicle.
If there are a lot of options,
equipment, passengers, or cargo in
the vehicle, it will reduce the tongue
weight the vehicle can carry, which
will also reduce the trailer weight the
vehicle can tow. If towing a trailer,
the tongue load must be added to
the GVW because the vehicle will
be carrying that weight, too. See
Vehicle Load Limits 0166.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Vehicle Care 227
Vehicle Care
General Information
General Information . . . . . . . . . . 228
California Proposition65 Warning . . . . . . . . . . . . . . . . . 228
California Perchlorate Materials Requirements . . . . . 229
Accessories and Modifications . . . . . . . . . . . . . . . . 229
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . 229
Hood . . . . . . . . . . . . . . . . . . . . . . . . . 230
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 231
Engine Oil . . . . . . . . . . . . . . . . . . . . 234
Engine Oil Life System . . . . . . . 237
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . . 238
Engine Air Cleaner/Filter . . . . . . 238
Cooling System . . . . . . . . . . . . . . 239
Engine Overheating . . . . . . . . . . 243
Overheated Engine Protection Operating Mode . . . . . . . . . . . . . 244
Washer Fluid . . . . . . . . . . . . . . . . . 245
Brakes . . . . . . . . . . . . . . . . . . . . . . . 245
Brake Fluid . . . . . . . . . . . . . . . . . . . 246
Battery - North America . . . . . . 247 All-Wheel Drive . . . . . . . . . . . . . . . 248
Starter Switch Check . . . . . . . . . 248
Wiper Blade Replacement . . . . 249
Windshield Replacement . . . . . 249
Gas Strut(s) . . . . . . . . . . . . . . . . . . 249
Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 251
Bulb Replacement
Bulb Replacement . . . . . . . . . . . . 251
High Intensity Discharge (HID)
Lighting . . . . . . . . . . . . . . . . . . . . . 251
LED Lighting . . . . . . . . . . . . . . . . . 251
Taillamps, Turn Signal, Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 251
License Plate Lamp . . . . . . . . . . 252
Electrical System
Electrical System Overload . . . 253
Fuses and Circuit Breakers . . . 253
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 254
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . . 257
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . . 259
All-Season Tires . . . . . . . . . . . . . . 260
Winter Tires . . . . . . . . . . . . . . . . . . 260
Tire Sidewall Labeling . . . . . . . . 261 Tire Designations . . . . . . . . . . . . . 263
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 264
Tire Pressure . . . . . . . . . . . . . . . . . 266
Tire Pressure for High-Speed Operation . . . . . . . . . . . . . . . . . . . 267
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . . 268
Tire Pressure Monitor Operation . . . . . . . . . . . . . . . . . . . 269
Tire Inspection . . . . . . . . . . . . . . . . 272
Tire Rotation . . . . . . . . . . . . . . . . . 272
When It Is Time for New Tires . . . . . . . . . . . . . . . . . . . . . . . . 273
Buying New Tires . . . . . . . . . . . . . 274
Different Size Tires and Wheels . . . . . . . . . . . . . . . . . . . . . . 275
Uniform Tire Quality Grading . . . . . . . . . . . . . . . . . . . . . 276
Wheel Alignment and Tire Balance . . . . . . . . . . . . . . . . . . . . . 277
Wheel Replacement . . . . . . . . . . 277
Tire Chains . . . . . . . . . . . . . . . . . . . 278
If a Tire Goes Flat . . . . . . . . . . . . 279
Tire Sealant and Compressor Kit . . . . . . . . . . . . . 280
Storing the Tire Sealant and Compressor Kit . . . . . . . . . . . . . 287
Tire Changing . . . . . . . . . . . . . . . . 287
Compact Spare Tire . . . . . . . . . . 292

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
238 Vehicle Care
Automatic Transmission
Fluid
How to Check Automatic
Transmission Fluid
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.
There is a special procedure for
checking and changing the
transmission fluid. Because this
procedure is difficult, you should
have this done at your dealer
service department. Contact your
dealer for additional information or
the procedure can be found in the
service manual. To purchase a
service manual, seeService
Publications Ordering Information
0 334.
Change the fluid at the intervals
listed in Maintenance Schedule
0 311, and be sure to use the fluid
listed in Recommended Fluids and
Lubricants 0319.
Engine Air Cleaner/Filter
The engine air cleaner/filter is in the
engine compartment on the
passenger side of the vehicle. See
Engine Compartment Overview
0231.
When to Inspect the Engine Air
Cleaner/Filter
For intervals on changing and
inspecting the engine air cleaner/
filter, see Maintenance Schedule
0 311.
How to Inspect the Engine Air
Cleaner/Filter
Do not start the engine or have the
engine running with the engine air
cleaner/filter housing open. Before
removing the engine air cleaner/
filter, make sure that the engine air
cleaner/filter housing and nearby
components are free of dirt and
debris. Remove the engine air
cleaner/filter. Lightly tap and shake
the engine air cleaner/filter (away
from the vehicle), to release loose
dust and dirt. Inspect the engine air
cleaner/filter for damage, and replace if damaged. Do not clean
the engine air cleaner/filter or
components with water or
compressed air.
To inspect or replace the engine air
cleaner/filter:
2.5L L4 Engine