service BUICK LACROSSE 2007 Manual Online

Engine Coolant
The cooling system in the vehicle is lled with
DEX-COOL®engine coolant. This coolant
is designed to remain in the vehicle for ve years
or 150,000 miles (240 000 km), whichever
occurs rst, if only DEX-COOL
®extended life
coolant is added.
The following explains the cooling system and
how to add coolant when it is low. If there is
a problem with engine overheating or if coolant
needs to be added to the radiator, seeEngine
Overheating on page 367.A 50/50 mixture of clean, drinkable water and
DEX-COOL
®engine coolant will:
Give freezing protection down to−34°F (−37°C).
Give boiling protection up to 265°F (129°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Notice:Using coolant other than DEX-COOL
®
may cause premature engine, heater core, or
radiator corrosion. In addition, the engine
coolant may require changing sooner, at the rst
maintenance service after each 30,000 miles
(50 000 km) or 24 months, whichever occurs
rst. Any repairs would not be covered by your
warranty. Always use DEX-COOL
®(silicate-free)
coolant in your vehicle.
363

If No Steam Is Coming From Your
Engine
If you get an engine overheat warning, but see
or hear no steam, the problem may not be
too serious. Sometimes the engine can get a
little too hot when you:
Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer.
If you get the overheat warning with no sign of
steam, try this for a minute or so:
1. In heavy traffic, let the engine idle in
NEUTRAL (N) while stopped. If it is safe to
do so, pull off the road, shift to PARK (P)
or NEUTRAL (N) and let the engine idle.
2. Set the climate controls to the highest heat
setting and fan speed and open the windows
as necessary.If you no longer have the overheat warning,
you can drive. Just to be safe, drive slower for
about 10 minutes. If the warning does not
come back on, you can drive normally.
If the warning continues and you have not
stopped, pull over, stop, and park your vehicle
right away.
If there is still no sign of steam, you can idle the
engine for three minutes while you are parked.
If you still have the warning, turn off the engine
and get everyone out of the vehicle until it
cools down. Also, see “Overheated Engine
Protection Operating Mode” later in this section.
You may decide not to lift the hood but to get
service help right away.
369

When the engine is cold, the coolant level should
be at or above the cold ll line on the coolant
recovery tank. If it is not, there may be a leak at the
pressure cap or in the radiator hoses, heater hoses,
radiator, water pump, or somewhere else in the
cooling system.
{CAUTION:
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 re,
and you could be burned. Get any leak
xed before you drive the vehicle.If there seems to be no leak, with the engine on,
check to see if the electric engine cooling fans
are running. If the engine is overheating, the fans
should be running. If the fans are not running,
the vehicle needs service.
Notice:Engine damage from running your
engine without coolant is not covered by your
warranty. SeeOverheated Engine Protection
Operating Mode on page 370for information
on driving to a safe place in an emergency.
Notice:Using coolant other than DEX-COOL®
may cause premature engine, heater core,
or radiator corrosion. In addition, the engine
coolant could require changing sooner, at
30,000 miles (50 000 km) or 24 months,
whichever occurs rst. Any repairs would not
be covered by your warranty. Always use
DEX-COOL
®(silicate-free) coolant in your
vehicle.
372

5. Then ll the coolant recovery tank to the
cold ll line.
6. Reinstall the coolant recovery tank cap and
the pressure cap.
7. If the coolant in the recovery tank is constantly
low, you should have your dealership service
department inspect the vehicle for leaks.
Power Steering Fluid
SeeEngine
Compartment Overview
on page 350for
reservoir location.
When to Check Power Steering Fluid
It is not necessary to regularly check power
steering uid unless you suspect there is a leak
in the system or you hear an unusual noise.
A uid loss in this system could indicate a problem.
Have the system inspected and repaired.
378

{CAUTION:
The brake wear warning sound means that
soon the brakes will not work well. That
could lead to an accident. When you hear
the brake wear warning sound, have your
vehicle serviced.
Notice:Continuing to drive with worn-out
brake pads could result in costly brake repair.
Some driving conditions or climates may cause
a brake squeal when the brakes are rst applied or
lightly applied. This does not mean something is
wrong with your brakes.
Properly torqued wheel nuts are necessary to help
prevent brake pulsation. When tires are rotated,
inspect brake pads for wear and evenly tighten
wheel nuts in the proper sequence to GM torque
specications.
Brake linings should always be replaced as
complete axle sets.
Brake Pedal Travel
See your dealer if the brake pedal does not return
to normal height, or if there is a rapid increase in
pedal travel. This could be a sign of brake trouble.
Brake Adjustment
Every time you apply the brakes, with or without
the vehicle moving, your brakes adjust for wear.
Replacing Brake System Parts
The braking system on a vehicle is complex. Its
many parts have to be of top quality and work
well together if the vehicle is to have really good
braking. Your vehicle was designed and tested
with top-quality GM brake parts. When you replace
parts of your braking system — for example, when
your brake linings wear down and you need new
ones put in — be sure you get new approved
GM replacement parts. If you do not, your brakes
may no longer work properly. For example, if
someone puts in brake linings that are wrong for
your vehicle, the balance between your front
and rear brakes can change — for the worse.
The braking performance you have come to expect
can change in many other ways if someone puts
in the wrong replacement brake parts.
383

7. Do not let the other end touch metal. Connect
it to the positive (+) terminal location on
the vehicle with the good battery. Use a
remote positive (+) terminal if the vehicle
has one.
8. Now connect the black negative (−) cable to
the negative (−) terminal location on the
vehicle with the good battery. Use a remote
negative (−) terminal if the vehicle has one.
Do not let the other end touch anything
until the next step. The other end of the
negative (−) cable does not go to the dead
battery. It goes to a heavy, unpainted
metal engine part or to a remote negative (–)
terminal on the vehicle with the dead
battery.9. Connect the other end of the negative (−)
cable at least 18 inches (45 cm) away from
the dead battery, but not near engine
parts that move. The electrical connection
is just as good there, and the chance of
sparks getting back to the battery is
much less.
10. Now start the vehicle with the good battery
and run the engine for a while.
11. Try to start the vehicle that had the dead
battery. If it will not start after a few tries,
it probably needs service.
389

To disconnect the jumper cables from both
vehicles, do the following:
1. Disconnect the black negative (−) cable from
the vehicle that had the dead battery.
2. Disconnect the black negative (−) cable from
the vehicle with the good battery.
3. Disconnect the red positive (+) cable from the
vehicle with the good battery.
4. Disconnect the red positive (+) cable from the
other vehicle.
5. Return the fuse block cover to its original
position.
Headlamp Aiming
The vehicle has a visual optical headlamp aiming
system. The aim has been preset at the factory
and should need no further adjustment
However, If the vehicle is damaged in an accident,
the headlamp aim may be affected and adjustment
may be necessary.
If oncoming vehicles ash their high beams at
you, this may also mean the vertical aim needs to
be adjusted.It is recommended that the vehicle is taken to your
dealer for service if the headlamps need to be
re-aimed. It is possible however, to re-aim
the headlamps as described in the following
procedure.
The vehicle should be properly prepared as follows:
The vehicle should be placed so the headlamps
are 25 ft. (7.6 m) from a light colored wall.
The vehicle must have all four tires on a
perfectly level surface which is level all the way
to the wall.
The vehicle should be placed so it is
perpendicular to the wall.
The vehicle should not have any snow, ice or
mud on it.
The vehicle should be fully assembled and all
other work stopped while headlamp aiming is
being done.
The vehicle should be normally loaded with a
full tank of fuel and one person or 160 lbs
(75 kg) on the driver’s seat.
Tires should be properly inated.
391

Tires
Your new vehicle comes with high-quality tires
made by a leading tire manufacturer. If you ever
have questions about your tire warranty and where
to obtain service, see your GM Warranty booklet for
details. For additional information refer to the tire
manufacturer’s booklet included with your vehicle.
{CAUTION:
Poorly maintained and improperly used
tires are dangerous.
Overloading your vehicle’s tires can
cause overheating as a result of too
much friction. You could have an
air-out and a serious accident. See
Loading Your Vehicle on page 319.
Underinated tires pose the same
danger as overloaded tires. The
resulting accident could cause serious
injury. Check all tires frequently to
maintain the recommended pressure.
CAUTION: (Continued)
CAUTION: (Continued)
Tire pressure should be checked when
your vehicle’s tires are cold. See
Inflation - Tire Pressure on page 409.
Overinated tires are more likely to
be cut, punctured, or broken by a
sudden impact — such as when you
hit a pothole. Keep tires at the
recommended pressure.
Worn, old tires can cause accidents.
If the tire’s tread is badly worn, or
if your vehicle’s tires have been
damaged, replace them.
402

Tire Sidewall Labeling
Useful information about a tire is molded into its
sidewall. The examples below show a typical
passenger vehicle tire and a compact spare tire
sidewall.(A) Tire Size:The tire size is a combination of
letters and numbers used to dene a particular
tire’s width, height, aspect ratio, construction type,
and service description. See the “Tire Size”
illustration later in this section for more detail.
(B) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
(C) DOT (Department of Transportation):
The Department of Transportation (DOT) code
indicates that the tire is in compliance with the
U.S. Department of Transportation Motor Vehicle
Safety Standards.
(D) Tire Identication Number (TIN):The letters
and numbers following DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire
was manufactured. The TIN is molded onto both
sides of the tire, although only one side may
have the date of manufacture.
Passenger (P-Metric) Tire Example
403

(B) Tire Ply Material:The type of cord and
number of plies in the sidewall and under the tread.
(C) Tire Identication Number (TIN):The letters
and numbers following the DOT (Department of
Transportation) code is the Tire Identication
Number (TIN). The TIN shows the manufacturer
and plant code, tire size, and date the tire
was manufactured. The TIN is molded onto both
sides of the tire, although only one side may have
the date of manufacture.
(D) Maximum Cold Ination Load Limit:
Maximum load that can be carried and the
maximum pressure needed to support that load.
(E) Tire Ination:The temporary use tire or
compact spare tire should be inated to 60 psi
(420 kPa). For more information on tire pressure
and ination seeInation - Tire Pressure on
page 409.
(F) Tire Size:A combination of letters and
numbers dene a tire’s width, height, aspect ratio,
construction type, and service description. The
letter T as the rst character in the tire size means
the tire is for temporary use only.(G) TPC Spec (Tire Performance Criteria
Specication):Original equipment tires designed
to GM’s specic tire performance criteria have
a TPC specication code molded onto the sidewall.
GM’s TPC specications meet or exceed all
federal safety guidelines.
Tire Size
The following illustration shows an example of a
typical passenger vehicle tire size.
(A) Passenger (P-Metric) Tire:The United States
version of a metric tire sizing system. The letter P
as the rst character in the tire size means a
passenger vehicle tire engineered to standards
set by the U.S. Tire and Rim Association.
(B) Tire Width:The three-digit number indicates
the tire section width in millimeters from sidewall
to sidewall.
405