cooling BUICK LACROSSE 2005 User Guide

What to Use
Use a mixture of one-half clean, drinkable water and
one-half DEX-COOL®engine coolant which will
not damage aluminum parts. If this coolant mixture is
used, nothing else needs to be added.
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
Notice:If you use an improper coolant mixture,
your engine could overheat and be badly damaged.
The repair cost would not be covered by your
warranty. Too much water in the mixture can freeze
and crack the engine, radiator, heater core and
other parts.If coolant needs to be added more than four times a
year, have your dealer check the cooling system.
Notice:If you use the proper coolant, you do not
have to add extra inhibitors or additives which claim
to improve the system. These can be harmful.
Checking Coolant
The coolant recovery tank
is located in the engine
compartment toward
the rear of the engine on
the passenger’s side of the
vehicle. SeeEngine
Compartment Overview on
page 5-12for more
information on location.
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 ll line or a little higher. The cold ll line is
near the bottom of the surge tank and has an arrow
pointing down at it.3.8L V6 engine shown,
3.6L V6 engine similar
5-22

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 5-24.
{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 5-26.
5-23

Overheated Engine Protection
Operating Mode
This emergency operating mode allows your vehicle to
be driven to a safe place in an emergency situation. If an
overheated engine condition exists, an overheat
protection mode which alternates ring groups of
cylinders helps prevent engine damage. In this mode, you
will notice a signicant loss in power and engine
performance. The REDUCED POWER STOP WHEN
SAFE message will come on in the Driver Information
Center (DIC), along with the engine coolant temperature
warning light on the instrument panel, to indicate the
vehicle has entered overheated engine protection
operating mode. The temperature gage will also indicate
an overheat condition exists. Driving extended miles (km)
and/or towing a trailer in the overheat protection mode
should be avoided.
Notice:After driving in the overheated engine
protection operating mode, to avoid engine damage,
allow the engine to cool before attempting any repair.
The engine oil will be severely degraded. Repair the
cause of coolant loss, change the oil and reset the oil
life system. SeeEngine Oil on page 5-15.
Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Electric Engine Cooling Fans3.8L V6 engine
5-26

A. Coolant Recovery Tank
B. Radiator Pressure Cap
C. Electric Engine Cooling Fans
{CAUTION:
An electric engine cooling fan under the hood
can start up even when the engine is not
running and can injure you. Keep hands,
clothing and tools away from any underhood
electric fan.
If the coolant inside the coolant recovery tank is boiling,
do not do anything else until it cools down. The
vehicle should be parked on a level surface.
3.6L V6 engine
5-27

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. See
Overheated Engine Protection Operating Mode on
page 5-26for 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 may
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.
5-28

How to Add Coolant to the Coolant
Recovery Tank
{CAUTION:
Adding only plain water to your cooling
system can be dangerous. Plain water, or
some other liquid such as alcohol, can boil
before the proper coolant mixture will. Your
vehicle’s coolant warning system is set for the
proper coolant mixture. With plain water or the
wrong mixture, your engine could get too hot
but you would not get the overheat warning.
Your engine could catch re and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.If you have not found a problem yet, but the coolant
level is not at the cold ll line, add a 50/50 mixture
ofclean, drinkable waterand DEX-COOL
®engine
coolant at the coolant recovery tank. SeeEngine
Coolant on page 5-21for more information.
Notice:In cold weather, water can freeze and crack
the engine, radiator, heater core and other parts.
Use the recommended coolant and the proper
coolant mixture.
{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.
When the coolant level in the coolant recovery tank is at
the cold ll line, start the vehicle.
5-29

If the overheat warning continues, there is one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the system
is cool before you do it.
{CAUTION:
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 radiator
pressure cap — even a little — they can come
out at high speed. Never turn the cap when the
cooling system, including the radiator pressure
cap, is hot. Wait for the cooling system and
radiator pressure cap to cool if you ever have
to turn the pressure cap.
How to Add Coolant to the Radiator
Notice:Your engine has a specic radiator
ll procedure. Failure to follow this procedure could
cause your engine to overheat and be severely
damaged.
1. You can remove the
radiator pressure cap
when the cooling
system, including the
radiator pressure
cap and upper radiator
hose, is no longer
hot. Turn the pressure
cap slowly
counterclockwise until it
rst stops.
Do not press down while turning the pressure cap.
If you hear a hiss, wait for that to stop. A hiss
means there is still some pressure left.
2. Then keep turning the pressure cap, but now push
down as you turn it. Remove the pressure cap.
5-30

8. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fans.9. By this time, the coolant level inside the radiator
ller neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through the ller neck until the level reaches
the base of the ller neck.
10. Then replace the radiator pressure cap. At any time
during this procedure if coolant begins to ow out of
the ller neck, reinstall the pressure cap. Be sure
the pressure cap is hand-tight and fully seated.
11. Check the coolant in the recovery tank. The level in
the coolant recovery tank should be at the cold ll
line when the engine is cold.
3.8L V6 engine shown, 3.6L V6 engine similar
5-32

Wheel Replacement
Replace any wheel that is bent, cracked or badly rusted
or corroded. If wheel nuts keep coming loose, the
wheel, wheel bolts and wheel nuts should be replaced.
If the wheel leaks air, replace it (except some
aluminum wheels, which can sometimes be repaired).
See your dealer if any of these conditions exist.
Your dealer will know the kind of wheel you need.
Each new wheel should have the same load-carrying
capacity, diameter, width, offset and be mounted
the same way as the one it replaces.
If you need to replace any of your wheels, wheel bolts
or wheel nuts, replace them only with new GM
original equipment parts. This way, you will be sure to
have the right wheel, wheel bolts and wheel nuts
for your vehicle.{CAUTION:
Using the wrong replacement wheels, wheel
bolts or wheel nuts on your vehicle can be
dangerous. It could affect the braking and
handling of your vehicle, make your tires lose
air and make you lose control. You could have
a collision in which you or others could be
injured. Always use the correct wheel, wheel
bolts and wheel nuts for replacement.
Notice:The wrong wheel can also cause problems
with bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper height,
vehicle ground clearance and tire or tire chain
clearance to the body and chassis.
SeeChanging a Flat Tire on page 5-68for more
information.
5-65

Capacities and Specications
The following approximate capacities are given in English and metric conversions.
Capacities and Specications
ApplicationCapacities
English Metric
Air Conditioning Refrigerant R134a 2.31 lbs 1.05 kg
Automatic Transmission 7.4 qt 7.0 L
Cooling System Including Reservoir
3.6L V6
3.8L V611.0 qt
11.7 qt10.4 L
11.0 L
Engine Oil with Filter
3.6L V6
3.8L V65.5 quarts
4.5 quarts5.2 L
4.3 L
Fuel Tank 17.5 gallons 66.0 L
Wheel Nut Torque 100 ft lb 140Y
All capacities are approximate. When adding, be sure to ll to the approximate level, as recommended in this
manual. SeeScheduled Maintenance on page 6-4
Engine Specications
Engine VIN Code Transaxle Spark Plug Gap
3.6L V6 7 Automatic 0.044 inches (1.1 mm)
3.8 V6 2 Automatic 0.060 inches (1.52 mm)
5-92