
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

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Vehicle Care 255
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
1 –
2 –
3 ABS pump
5 AC DC inverter
6 Rear closure
7 Left corner lamp
8 Power windows/ Rearview mirror/
Power seats
9 Engine boost
10 Airbag sensing diagnostic module/
Passenger sensing
module—eAssist
11 DC DC Battery 1
12 Rear window defogger
13 Heated mirrors
14 – Fuses Usage
15 Passive entry/ Passive start
16 Front wipers
17 Passenger power seat
18 ABS valve
19 Driver power seat
21 Sunroof
22 Right corner lamp
23 Auto headlamp leveling
24 –
26 Transmission control module/Ignition
27 Instrument panel/ Ignition
28 Electronic precision shift/Ignition
29 Rear vision camera/ Ventilation
30 Malfunction indicator lamp/Shift solenoid Fuses Usage
32 Canister vent solenoid
33 Front heated seats
34 BSM (eAssist)/Fan control module/
Damping control
module (SADS)
35 Fog lamps
36 Fuel module
38 –
39 –
40 Steering columnn lock
41 –
43 Heated steering wheel
44 Headlamp leveling/ Rear seat ventilation
45 –
46 Engine control module/Ignition
47 –

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
256 Vehicle Care
FusesUsage
48 Engine boost/Left cooling fan
49 DC DC battery 2/AWD
50 –
51 –
52 –
53 –
54 –
55 –
56 –
57 Transmission auxiliary pump
58 TRCM
59 High-beam headlamps
60 Cooling fan
61 –
62 –
63 –
65 A/C HEV Fuses
Usage
67 –
68 –
69 Right HID low-beam headlamps
70 Left HID low-beam headlamps
72 Starter pinion
74 Starter motor
75 Engine control module
76 Powertrain –off
engine
77 –
78 Horn
79 Washer pump
81 Transmission control module/ Engine
control module
82 –
83 Ignition coils
84 Coil Fuses
Usage
85 Engine control module switch 2
86 Engine control module switch 1
87 SAI reaction pump
88 Aeroshutter
89 Headlamp washer
91 –
92 TPIM motor generator unit pump
93 Headlamp leveling
95 SAI reaction solenoid
96 Fuel heater
97 –
99 Coolant pump
Relays Usage
4 AC DC inverter
20 Rear defogger
25 Front wiper control
31 Run/Crank

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
Vehicle Care 257
RelaysUsage
37 Front wiper speed
42 Transmission auxiliary pump
64 A/C control
66 Powertrain
71 HID low-beam headlamps
73 Starter motor
80 Starter pinion
90 SAI reaction solenoid
94 Headlamp washer
98 SAI reaction pumpInstrument Panel Fuse
Block
The instrument panel fuse block is
in the instrument panel, on the
driver side of the vehicle. To operate
the fuses, open the fuse panel by
pulling down at the top.
Pull the panel toward you to release
it from the hinges.

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
258 Vehicle Care
The vehicle may not be equipped
with all of the fuses, relays, and
features shown.Fuses Usage
F1 Left window
F2 Right window
F3 –
F4 HVAC blower
F5 Battery 2 Fuses
Usage
F6 Electric steering column
F7 –
F8 Battery 3
F9 Engine control module/Battery
F10 Body control module 2 On/Off Fuses
Usage
F11 –
F12 –
F13 –
F14 –
F15 Transmission control module On/Off
F16 Amplifier
F17 –
F18 Battery 7
F19 –
F20 Battery 1
F21 Battery 4
F22 Battery 6
F23 Electric steering column lock
F24 Airbag sensing diagnostic module/
Passenger sensing
module
F25 Diagnostic link
F26 –
F27 AC DC inverter

Buick LaCrosse Owner Manual (GMNA-Localizing-U.S./Canada-10999169) -
2018 - crc - 3/28/17
264 Vehicle Care
Tire Terminology and
Definitions
Air Pressure:The amount of
air inside the tire pressing
outward on each square inch of
the tire. Air pressure is
expressed in kPa (kilopascal)
or psi (pounds per square inch).
Accessory Weight
:The
combined weight of optional
accessories. Some examples of
optional accessories are
automatic transmission, power
windows, power seats, and air
conditioning.
Aspect Ratio
:The relationship
of a tire's height to its width.
Belt
:A rubber coated layer of
cords between the plies and the
tread. Cords may be made from
steel or other reinforcing
materials. Bead
:The tire bead contains
steel wires wrapped by steel
cords that hold the tire onto
the rim.
Bias Ply Tire
:A pneumatic tire
in which the plies are laid at
alternate angles less than
90 degrees to the centerline of
the tread.
Cold Tire Pressure
:The
amount of air pressure in a tire,
measured in kPa (kilopascal)
or psi (pounds per square inch)
before a tire has built up heat
from driving. See Tire Pressure
0 266.
Curb Weight
:The weight of a
motor vehicle with standard and
optional equipment including the
maximum capacity of fuel, oil,
and coolant, but without
passengers and cargo.
DOT Markings
:A code molded
into the sidewall of a tire
signifying that the tire is in
compliance with the U.S. Department of Transportation
(DOT) Motor Vehicle Safety
Standards. The DOT code
includes the Tire Identification
Number (TIN), an alphanumeric
designator which can also
identify the tire manufacturer,
production plant, brand, and
date of production.
GVWR
:Gross Vehicle Weight
Rating. See Vehicle Load Limits
0 166.
GAWR FRT
:Gross Axle Weight
Rating for the front axle. See
Vehicle Load Limits 0166.
GAWR RR
:Gross Axle Weight
Rating for the rear axle. See
Vehicle Load Limits 0166.
Intended Outboard Sidewall
:
The side of an asymmetrical tire
that must always face outward
when mounted on a vehicle.
Kilopascal (kPa)
:The metric
unit for air pressure.