ECU BUICK LACROSSE 2008 Service Manual

Weight of the Trailer
How heavy can a trailer safely be?
It should never weigh more than 1,000 lbs (450 kg). But
even that can be too heavy.
It depends on how you plan to use your rig. For
example, speed, altitude, road grades, outside
temperature and how much the vehicle is used to pull a
trailer are all important. It can also depend on any
special equipment that is 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 must be subtracted
from the maximum trailer weight.
Ask your dealer/retailer for our trailering information or
advice, or write us at our Customer Assistance
Offices. SeeCustomer Assistance Offices on page 7-6
for 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 or gross weight
of the vehicle. The Gross Vehicle Weight (GVW)
includes the curb weight of the vehicle, any cargo 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. And if you tow a trailer, you
must add the tongue load to the GVW because the
vehicle will be carrying that weight, too. SeeLoading
Your Vehicle on page 4-21for more information
about the vehicle’s maximum load capacity.
4-30

Trailer Brakes
Does your trailer have its own brakes? Be sure to read
and follow the instructions for the trailer brakes so
you’ll be able to install, adjust and maintain them
properly.
If your vehicle has antilock brakes, do not try to tap
into your vehicle’s brake system. If you do, both
brake systems will not work well, or at all.
Even if your vehicle does not have antilock
brakes, do not tap into your vehicle’s brake system
if the trailer’s brake system will use more than
0.02 cubic inch (0.3 cc) of uid from your vehicle’s
master cylinder. If it does, both braking systems
will not work well. You could even lose your brakes.
Will the trailer brake parts take 3,000 psi
(20 650 kPa) of pressure? If not, the trailer brake
system must not be used with your vehicle.
If everything checks out this far, then make the
brake uid tap at the upper rear master cylinder
port. But do not use copper tubing for this. If you do,
it will bend and break off. Use steel brake tubing.
Driving with a Trailer
Towing a trailer requires a certain amount of experience.
Before setting out for the open road, get to know the rig.
Acquaint yourself with the feel of handling and braking
with the added weight of the trailer. And always keep in
mind that the vehicle is now a good deal longer and not
nearly as responsive as the vehicle is by itself.
Before starting, check all trailer hitch parts and
attachments, safety chains, electrical connector, lamps,
tires, and mirror adjustment. If the trailer has electric
brakes, start the vehicle and trailer moving and
then apply the trailer brake controller by hand to be sure
the brakes are working. This lets you check the
electrical connection at the same time.
During your trip, check occasionally to be sure that the
load is secure, and that the lamps and any trailer
brakes are still working.
4-32

Hood Release
To open the hood, do the following:
1. Pull the interior hood
release handle with
this symbol on it. It is
located to the left of the
steering column below
the instrument panel.
2. Push the secondary hood release lever, located
under the center of the hood above the grille, up
and to the right to disengage it.
3. Lift the hood.
Before closing the hood, make sure all the ller caps
are properly secured. Pull the hood down and close
it rmly.
5-11

The vehicle must be on a level surface when checking
the coolant level.
When the engine is cold, the coolant level should be at
the COLD FILL line or a little higher. The COLD FILL
line is near the bottom of the recovery tank and has an
arrow pointing down at it.
Adding Coolant
If more coolant is needed, add the proper DEX-COOL®
coolant mixture at the coolant recovery tank, but be
careful not to spill it.
If the coolant recovery tank is completely empty, add
coolant to the radiator. SeeEngine Overheating
on page 5-30.
{CAUTION:
Turning the radiator pressure cap when the
engine and radiator are hot can allow steam
and scalding liquids to blow out and burn you
badly. With the coolant recovery tank, you will
almost never have to add coolant at the
radiator. Never turn the radiator pressure
cap — even a little — when the engine and
radiator are hot.
{CAUTION:
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.
Occasionally check the coolant level in the radiator. For
information on how to add coolant to the radiator,
seeCooling System on page 5-33.
Radiator Pressure Cap
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.
The radiator pressure cap is located in the front of the
engine compartment on the passenger’s side of the
vehicle. SeeEngine Compartment Overview on
page 5-12for more information on location.
5-29

Pressure Cap
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.
SeeEngine Compartment Overview on page 5-12for
more information on location.
Engine Overheating
There is a coolant temperature gage and a warning light
on the instrument panel cluster that indicate an
overheated engine condition. SeeEngine Coolant
Temperature Gage on page 3-40andEngine Coolant
Temperature Warning Light on page 3-40for more
information.
In addition, if your vehicle is equipped with a Driver
Information Center (DIC), you will nd an ENGINE
COOLANT HOT and a REDUCED POWER STOP
WHEN SAFE message displayed on the DIC. SeeDIC
Warnings and Messages on page 3-58for more
information.
5-30

CAUTION: (Continued)
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions.To help avoid damage to your
vehicle, drive slowly, readjust or remove the
device if it is contacting your vehicle, and do
not spin your wheels.
If you do nd traction devices that will t, install
them on the front tires.Notice:If your vehicle has a tire size other than
P225/55R17 or P235/50R18 size tires, use tire chains
only where legal and only when you must. Use only
SAE Class “S” type chains that are the proper size for
your tires. Install them on the front tires and tighten
them as tightly as possible with the ends securely
fastened. Drive slowly and follow the chain
manufacturer’s instructions. If you can hear the
chains contacting your vehicle, stop and retighten
them. If the contact continues, slow down until it
stops. Driving too fast or spinning the wheels with
chains on will damage your vehicle.
5-85

Removing the Wheel Nuts
1. Place the wheel wrench securely over the wheel
nut. Turn the wheel wrench counterclockwise to
loosen all the wheel nuts, but do no remove them yet.
2. Turn the jack handle clockwise to raise the jack
lift head.
3. Find the jacking location using the diagram above
and corresponding triangular-shaped hoisting
notches located on the underside of the vehicle’s
plastic molding.The front location is about 6.5 inches (16.5 cm)
from the rear edge of the front wheel well. The rear
location is about 9 inches (22.8 cm) from the front
edge of the rear wheel well.
{CAUTION:
Getting under a vehicle when it is jacked up is
dangerous. If the vehicle slips off the jack you
could be badly injured or killed. Never get
under a vehicle when it is supported only by
a jack.
{CAUTION:
Raising your vehicle with the jack improperly
positioned can damage the vehicle and even
make the vehicle fall. To help avoid personal
injury and vehicle damage, be sure to t the
jack lift head into the proper location before
raising the vehicle.
4. Put the compact spare tire near you.
5-90

Storing a Flat or Spare Tire and
Tools (Base Model)
{CAUTION:
Storing a jack, a tire, or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision,
loose equipment could strike someone. Store
all these in the proper place.
After the compact spare tire has been installed on the
vehicle, store the at tire in the trunk.
When storing a full-size tire, use the extension with the
extension protector, located in the foam holder, to help
avoid wheel surface damage.To store a full-size tire:
1. Install the tools in their original location in the trunk
area and secure.
2. Place the tire valve stem facing down and the
protector/guide placed through a wheel bolt hole.
3. Remove the protector and attach the retainer
securely
4. Store the cover as far forward as possible.
When storing a compact spare tire in the trunk, put the
protector back in the foam holder.
The compact spare is for temporary use only. Replace
the compact spare tire with a full-size tire as soon as
you can. SeeCompact Spare Tire on page 5-98. Use this
as a guide for storing the compact spare tire and tools.
5-95

Storing a Flat or Spare Tire and
Tools (Super Only)
Super Model
{CAUTION:
Storing a jack, a tire, or other equipment in the
passenger compartment of the vehicle could
cause injury. In a sudden stop or collision,
loose equipment could strike someone. Store
all these in the proper place.
After the compact spare tire has been installed on the
vehicle, store the at tire in the trunk.
When storing a full-size tire, use the extension with the
protector, located in the foam holder, to help avoid
wheel surface damage.
To store a full-size tire:
1. Install the tools in their original location in the trunk
area and secure.
2. Place the tire valve stem facing down and the
protector/guide placed through a wheel bolt hole.3. Remove the protector and attach the retainer
securely
4. Store the cover as far forward as possible.
When storing a compact spare tire in the trunk, put the
protector back in the foam holder. When storing the
compact spare tire, the tire must be stored valve
stem down.
The compact spare is for temporary use only. Replace
the compact spare tire with a full-size tire as soon as
you can. SeeCompact Spare Tire on page 5-98. Use this
as a guide for storing the compact spare tire and tools.
Compact Spare Tire
5-97

Engine Coolant Level Check
Check the engine coolant level and add DEX-COOL®
coolant mixture if necessary. SeeEngine Coolant
on page 5-27.
Windshield Washer Fluid Level Check
Check the windshield washer uid level in the windshield
washer uid reservoir and add the proper uid if
necessary.
At Least Once a Month
Tire Ination Check
Inspect your vehicle’s tires and make sure they are
inated to the correct pressures. Do not forget to check
the spare tire. SeeInflation - Tire Pressure on
page 5-70. Check to make sure the spare tire is stored
securely. SeeChanging a Flat Tire on page 5-87.
Tire Wear Inspection
Tire rotation may be required for high mileage highway
drivers prior to the Engine Oil Life System service
notication. Check the tires for wear and, if necessary,
rotate the tires. SeeTire Inspection and Rotation on
page 5-75.
At Least Once a Year
Starter Switch Check
{CAUTION:
When you are doing this inspection, the
vehicle could move suddenly. If the vehicle
moves, you or others could be injured.
1. Before you start, be sure you have enough room
around the vehicle.
2. Firmly apply both the parking brake and the regular
brake. SeeParking Brake on page 2-32.
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 PARK (P) or NEUTRAL (N). If
the vehicle starts in any other position, contact your
dealer/retailer for service.
6-9