cooling PONTIAC GRAND PRIX 2006 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 extra inhibitors and/or additives
in your vehicle’s cooling system, you could
damage your vehicle. Use only the proper mixture
of the engine coolant listed in this manual for
the cooling system. SeeRecommended Fluids and
Lubricants on page 6-12for more information.
5-26

Checking Coolant
The coolant recovery tank
cap has this symbol on it.
SeeEngine Compartment Overview on page 5-12
for more information on the location of the coolant
recovery tank.
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
marked with the same symbol as the coolant recovery
tank cap.
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 5-28.
{CAUTION:
Turning the 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 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 5-30.
5-27

Overheated Engine Protection
Operating Mode
The overheated engine protection operating mode
allows the vehicle to be driven to a safe place in an
emergency situation. If an overheated engine condition
exists, this protection mode alternates ring groups
of cylinders to help prevent engine damage. In
this mode, there will be a signicant loss in power and
engine performance. The engine coolant temperature
gage indicator will move to the shaded area, and
the engine coolant temperature warning light will come
on, showing that an overheated engine condition
exists. Driving extended miles (km) and/or towing a
trailer in the overheated engine 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 5-16.
Cooling System
When you decide it is safe to lift the hood, here is what
you will see:
A. Coolant Recovery Tank
B. Electric Engine Cooling Fan(s)
C. Pressure Cap3800 V6 Supercharged Engine shown, 3800 V6
Engine similar
5-30

A. Pressure Cap
B. Electric Engine Cooling Fans
C. Coolant Recovery Tank
{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.
The coolant recovery tank is located in the rear of the
engine compartment on the passenger’s side of the
vehicle on the 3800 V6 engines. The coolant recovery
tank on the 5.3L V8 engine is located in the rear of
the engine compartment on the driver’s side of
the vehicle, behind the engine air cleaner/lter. 5.3L V8 Engine
5-31

When the engine is cold, the coolant level should be at
or above the cold ll line on the coolant recovery
tank. To check the coolant level, look for the cold ll line
on the side of the coolant recovery tank that faces the
engine. If the level is not correct, 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 fan(s) are running.
If the engine is overheating, the fan(s) should be
running. If the fan(s) 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 5-30for 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.
5-32

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
of clean, drinkable water and DEX-COOL
®engine
coolant at the coolant recovery tank. SeeEngine
Coolant on page 5-25for 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.
5-33

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
pressure cap — even a little — they can come
out at high speed. Never turn the cap when the
cooling system, including the pressure cap, is
hot. Wait for the cooling system and pressure
cap to cool if you ever have to turn the
pressure cap.
How to Add Coolant to the Radiator
(3800 V6 Engines)
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 pressure cap when the cooling
system, including the pressure cap and upper
radiator hose, is no longer hot. Turn the cap slowly
counterclockwise.
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 and remove it.3800 V6 Supercharged Engine shown, 3800 V6
Engine similar
5-34

10. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan(s).11. 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.
12. Then replace the 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.
13. 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.
3800 V6 Supercharged Engine shown, 3800 V6
Engine similar
5-38

How to Add Coolant to the Cooling
System (5.3L V8 Engine)
Notice:Your engine has a specic cooling system
drain and ll procedure. Failure to follow this
procedure could cause your engine to overheat
and be severely damaged. If your engine’s cooling
system needs to be drained and re-lled, please see
your dealer.
You can remove the
pressure cap when the
cooling system, including
the pressure cap and
upper radiator hose is no
longer hot. Turn the
pressure cap slowly
counterclockwise.
1. If you hear a hiss, wait for that to stop. A hiss
means that there is still some pressure left.
2. Then keep turning the pressure cap to remove the
pressure cap.
{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.
3. Fill the cooling system with the proper DEX-COOL
®
coolant mixture, up to the base of the ller neck.
SeeEngine Coolant on page 5-25for more
information about the proper coolant mixture.
4. Rinse or wipe any spilled coolant from the engine
and the compartment.
5. Then ll the coolant recovery tank to the cold
ll line.
6. Install the coolant recovery tank cap and the
pressure cap.
7. If the coolant in the recovery tank is constantly low,
you should have a dealership service department
inspect your vehicle for leaks.
5-39

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 5-88for more
information.
Used Replacement Wheels
{CAUTION:
Putting a used wheel on your vehicle is
dangerous. You cannot know how it has been
used or how far it has been driven. It could fail
suddenly and cause a crash. If you have to
replace a wheel, use a new GM original
equipment wheel.
5-76