2010 BUICK LACROSSE cooling

Driving and Operating 8-57
If parking the rig on a hill:
1. Press the brake pedal, but donot 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
into P (Park).
5. Release the brake pedal.Leaving After Parking on a Hill
1. Apply and hold the brake pedal while you:
.Start the 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
The vehicle needs service more
often when pulling a trailer. See this
manual's Maintenance Schedule or
Index for more information. Things
that are especially important in
trailer operation are automatic
transmission fluid, engine oil, axle
lubricant, belts, cooling system and
brake system. Inspect these before
and during the trip.
Check periodically to see that all
hitch nuts and bolts are tight.

8-58 Driving and Operating
Engine Cooling When Trailer
Towing
The cooling system may temporarily
overheat during severe operating
conditions. SeeEngine Overheating
on page 9‑20.
Trailer Towing
(2.4L L4 Engine)
Vehicles with a four cylinder engine
are neither designed nor intended to
tow a trailer.
Trailer Towing (3.0L and
3.6L V6 Engines)
Before pulling a trailer, there are
three important considerations that
have to do with weight:
.The weight of the trailer.
.The weight of the trailer tongue.
.The total weight on your
vehicle's tires.
Weight of the Trailer
How heavy can a trailer safely be?
For a vehicle with a V6 engine, it
should never weigh more than
454 kg (1,000 lbs). But even that
can be too heavy.
It depends on how the rig is used.
For example, speed, altitude, road
grades, outside temperature 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”
later in this section for more
information.
Maximum trailer weight is calculated
assuming only the driver is in the
tow vehicle and it has 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/retailer for trailering
information or advice, or write us at
our Customer Assistance Offices.
See
Customer Assistance Offices
(US, Can)
on page 12‑3for more
information.
Weight of the Trailer Tongue
The tongue load (A) 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
on page 8‑12for more information.

Vehicle Care 9-1
Vehicle Care
General Information
General Information . . . . . . . . . . . 9-2
California Proposition65 Warning . . . . . . . . . . . . . . . . . . 9-2
California Perchlorate Materials Requirements . . . . . . . . . . . . . . . 9-3
Accessories and Modifications . . . . . . . . . . . . . . . . 9-3
Vehicle Checks
Doing Your OwnService Work . . . . . . . . . . . . . . . . 9-4
Hood . . . . . . . . . . . . . . . . . . . . . . . . . . 9-5
Engine Compartment Overview . . . . . . . . . . . . . . . . . . . . 9-6
Engine Oil . . . . . . . . . . . . . . . . . . . 9-11
Engine Oil Life System . . . . . . 9-13
Automatic Transmission Fluid . . . . . . . . . . . . . . . . . . . . . . . 9-15
Engine Air Cleaner/Filter . . . . . 9-15
Cooling System . . . . . . . . . . . . . . 9-17
Engine Coolant . . . . . . . . . . . . . . 9-18
Engine Overheating . . . . . . . . . 9-20
Overheated Engine Protection Operating Mode . . . . . . . . . . . . 9-21
Power Steering Fluid . . . . . . . . 9-22 Washer Fluid . . . . . . . . . . . . . . . . 9-23
Brakes . . . . . . . . . . . . . . . . . . . . . . . 9-24
Brake Fluid . . . . . . . . . . . . . . . . . . 9-25
Battery . . . . . . . . . . . . . . . . . . . . . . . 9-26
Starter Switch Check . . . . . . . . 9-27
Automatic Transmission Shift
Lock Control System
Check . . . . . . . . . . . . . . . . . . . . . . 9-27
Ignition Transmission Lock Check . . . . . . . . . . . . . . . . . . . . . . 9-28
Park Brake and P (Park) Mechanism Check . . . . . . . . . 9-28
Wiper Blade Replacement . . . 9-29Headlamp Aiming
Headlamp Aiming . . . . . . . . . . . . 9-30
Bulb Replacement
Bulb Replacement . . . . . . . . . . . 9-33
Halogen Bulbs . . . . . . . . . . . . . . . 9-33
High Intensity Discharge (HID) Lighting . . . . . . . . . . . . . . . . . . . . 9-33
Headlamps, Front Turn Signal and Parking Lamps . . . . . . . . . 9-33
Fog Lamps . . . . . . . . . . . . . . . . . . 9-35 Taillamps, Turn Signal,
Stoplamps, and Back-Up
Lamps . . . . . . . . . . . . . . . . . . . . . . 9-35
License Plate Lamp . . . . . . . . . . 9-36
Replacement Bulbs . . . . . . . . . . 9-37
Electrical System
Electrical System Overload . . . . . . . . . . . . . . . . . . . 9-38
Fuses and Circuit Breakers . . . . . . . . . . . . . . . . . . . 9-38
Engine Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . 9-39
Instrument Panel Fuse Block . . . . . . . . . . . . . . . . . . . . . . . 9-41
Rear Compartment Fuse Block . . . . . . . . . . . . . . . . . . . . . . . 9-43
Wheels and Tires
Tires . . . . . . . . . . . . . . . . . . . . . . . . . 9-46
Winter Tires . . . . . . . . . . . . . . . . . . 9-46
Tire Sidewall Labeling . . . . . . . 9-47
Tire Designations . . . . . . . . . . . . 9-49
Tire Terminology and
Definitions . . . . . . . . . . . . . . . . . . 9-50
Tire Pressure . . . . . . . . . . . . . . . . 9-53
Tire Pressure Monitor System . . . . . . . . . . . . . . . . . . . . . 9-54

Vehicle Care 9-17
Cooling System
The cooling system allows the
engine to maintain the correct
working temperature.
When it is safe to lift the hood:
2.4 L L4 Engine
A. Electric Engine Cooling Fan
B. Coolant Recovery Tank andPressure Cap 3.0 L V6 Engine shown,
3.6 L V6 Engine similar
A. Electric Engine Cooling Fans
B. Coolant Recovery Tank and
Pressure Cap
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{WARNING
Heater and radiator hoses, and
other engine parts, can be very
hot. Do not touch them. If you do,
you can be burned.
Do not run the engine if there is a
leak. If you run the engine, it
could lose all coolant. That could
cause an engine fire, and you
could be burned. Get any leak
fixed before you drive the vehicle.
Notice: Using coolant other than
DEX-COOL
®can cause premature
engine, heater core, or radiator
corrosion. In addition, the engine
coolant could require changing
sooner, at 50 000 km
(30,000 miles) or 24 months,
whichever occurs first. Any
repairs would not be covered by
the vehicle warranty. Always use
DEX-COOL
®(silicate-free) coolant
in the vehicle.

9-18 Vehicle Care
Engine Coolant
The cooling system in the vehicle is
filled with DEX-COOL®engine
coolant. This coolant is designed to
remain in the vehicle for five years
or 240 000 km (150,000 miles),
whichever occurs first.
The following explains the cooling
system and how to check and add
coolant when it is low. If there is a
problem with engine overheating,
see Engine Overheating
on
page 9‑20.
What to Use
{WARNING
Adding only plain water to the
cooling system can be
dangerous. Plain water, or some
other liquid such as alcohol, can
boil before the proper coolant
mixture will. The vehicle's coolant
warning system is set for the
proper coolant mixture. With plain
(Continued)
WARNING (Continued)
water or the wrong mixture, the
engine could get too hot but you
would not get the overheat
warning. The engine could catch
fire and you or others could be
burned. Use a 50/50 mixture of
clean, drinkable water and
DEX-COOL
®coolant.
Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®
coolant. If using this mixture,
nothing else needs to be added.
This mixture:
.Gives freezing protection down
to −37°C (−34°F), outside
temperature.
.Gives boiling protection up to
129°C (265°F), engine
temperature.
.Protects against rust and
corrosion.
.Will not damage aluminum parts.
.Helps keep the proper engine
temperature.
Notice: If an improper coolant
mixture is used, the engine could
overheat and be badly damaged.
The repair cost would not be
covered by the vehicle warranty.
Too much water in the mixture
can freeze and crack the engine,
radiator, heater core, and other
parts.
Checking Coolant
The vehicle must be on a level
surface when checking the coolant
level.
Check to see if coolant is visible in
the coolant recovery tank. If the
coolant inside the coolant recovery
tank is boiling, do not do anything
else until it cools down. If coolant is
visible but the coolant level is not at
or above the mark pointed to, add a
50/50 mixture of clean, drinkable
water and DEX-COOL
®coolant at

Vehicle Care 9-19
the coolant recovery tank, but be
sure the cooling system is cool
before this is done.
If no coolant is visible in the surge
tank, add coolant as follows:
How to Add Coolant to the
Recovery Tank
{WARNING
You can be burned if you spill
coolant on hot engine parts.
Coolant contains ethylene glycol
and it will burn if the engine parts
are hot enough. Do not spill
coolant on a hot engine.
Notice: This vehicle has a
specific coolant fill procedure.
Failure to follow this procedure
could cause the engine to
overheat and be severely
damaged.
{WARNING
An electric engine cooling fan
under the hood can start up even
when the engine is not running
and can cause injury. Keep
hands, clothing, and tools away
from any underhood electric fan.
{WARNING
Steam and scalding liquids from a
hot cooling system can blow out
and burn you badly. They are
under pressure, and if you turn
the surge tank pressure
cap —even a little —they can
come out at high speed. Never
turn the cap when the cooling
system, including the surge tank
pressure cap, is hot. Wait for the
cooling system and surge tank
pressure cap to cool if you ever
have to turn the pressure cap.
The coolant surge tank pressure
cap can be removed when the
cooling system, including the surge
tank pressure cap and upper
radiator hose, is no longer hot.
1. Turn the pressure cap slowly counterclockwise. If a hiss is
heard, wait for that to stop.
A hiss means there is still some
pressure left.
2. Then keep turning the cap and remove it.

9-20 Vehicle Care
3. Fill the coolant surge tank withthe proper mixture to the mark
pointed to on the front of the
coolant surge tank.
4. With the coolant surge tank cap off, start the engine and let it run
until the upper radiator hose
starts getting hot. Watch out for
the engine cooling fan(s). By this
time, the coolant level inside the
coolant surge tank may be
lower. If the level is lower, add
more of the proper mixture to the
coolant surge tank until the level reaches the mark pointed to on
the front of the coolant
surge tank.
5. Replace the cap. Be sure the cap is hand–tight and full
seated.
Notice: If the pressure cap is not
tightly installed, coolant loss and
possible engine damage may
occur. Be sure the cap is properly
and tightly secured.
If coolant is needed, add the proper
DEX-COOL®coolant mixture at the
coolant recovery tank.
Engine Overheating
The vehicle has several indicators
to warn of engine overheating.
There is a coolant temperature gage
and a warning light on the
instrument panel cluster that
indicate an overheated engine
condition. See Engine Coolant
Temperature Gage
on page 4‑15for more information. You may decide not to lift the hood
when this warning appears, but
instead get service help right away.
See
Roadside Assistance Program
(US, Can) on page 12‑6.
If you do decide to lift the hood ,
make sure the vehicle is parked on
a level surface.
Then check to see if the engine
cooling fans are running. If the
engine is overheating, the fan(s)
should be running. If they are not,
do not continue to run the engine
and have the vehicle serviced.
Notice: Engine damage from
running the engine without
coolant is not covered by the
warranty.
If Steam Is Coming From The
Engine Compartment
See Overheated Engine Protection
Operating Modeon page 9‑21for
information on driving to a safe
place in an emergency.

9-40 Vehicle Care
J-CaseFuses Usage
28 Rear Window
Defogger
41 Brake
Vacuum Pump
42 Cooling Fan K2
45 Cooling Fan K1
Mini Fuses Usage 1 Transmission
Control Module
2 Engine Control
Module Battery
5 Engine Control
Module Ignition
8 Ignition Coils ‐Even
9 Ignition Coils ‐Odd
10 Engine Control
Module Mini Fuses Usage
11 Post Catalytic
Converter Oxygen
Sensor Heater
13 Trans Ignition / Fuel
System Control
Module
16 MAF
17 Airbag Module
18 SBZ Ignition
23 Variable Effort
Steering
29 Power Lumbar, Left
32 Body Control
Module
33 Heated Seat
34 Antilock Brake
System Valves
35 Amplifier
36 AFL Ignition
37 Right High Beam Mini Fuses Usage
38 Left High Beam
46 Cooling Fan Relay
47 Pre Catalytic
Converter Oxygen
Sensor Heater
48 Fog Lamps
49 Right High Intensity
Discharge
Headlamp
50 Left High Intensity
Discharge
Headlamp
51 Horn
52 Cluster Ignition
53 Inside Rearview
Mirror, Rear Vision
Camera,
Vacuum Pump
54 Heating, Ventilation
and Air Conditioning