Page 228 of 410
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 first
stops. (Don’t 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.
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. Don’t
spill coolant on a hot engine.
5-23
Page 229 of 410
3. After the engine cools, open the air bleed valves on
the heater return hose and water pump inlet.
4. Fill with the proper DEX-COOL' coolant mixture.
Add
coolant until you see a steady stream of coolant
coming from the bleed valves.
5. Close the bleed valves.
6. Continue to fill the radiator up to the base of the
7. Rinse or wipe the spilled coolant from the engine
filler neck.
and compartment.
5-24
Page 230 of 410
8. Start the engine and allow it to run in idle for
approximately four minutes. By this time, the
coolant level inside the radiator will be lower. Add
more of the proper mix through the filler neck until
the level reaches the base
of the filler neck.
9. Shut the engine off and replace the pressure cap. Be
sure the arrows on the cap line up like this.
10. Then fill the coolant recovery tank to the
For a complete drain,
flush and refill, see your Pontiac
dealer or a Pontiac Firebird Service Manual.
To
purchase a service manual, see “Service and Owner
Publications” in the Index.
proper
level.
5-25
Page 267 of 410

1 Vf a I IJ
If you have the 5.7L LT1 engine (with the WS6 option),
your air cleaner will be located over the radiator near the
front
of the engine.
To remove the filter, remove the screws (located on the
rear edge of the air cleaner), lift the air cleaner and
remove
the filter.
Automatic Transmission Fluid
When to Check and Change
A good time to check your automatic transmission fluid
level is when the engine oil is changed.
Change both the fluid and filter every 15,000 miles
(25 000 km) if the vehicle is mainly driven under one
or more of these conditions:
In heavy city traffic where the outside temperature
0 In hilly or mountainous terrain.
regularly reaches
90” F (32” C) or higher.
0 Uses such as high
performance operation.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If you do
not use your vehicle under any of these
conditions, change the fluid and filter every
100,000 miles ( 166 000 km),
See “Scheduled Maintenance Services” in the Index.
6-22
Page 274 of 410

Rear Axle
When to Check and Change Lubricant
Refer to the Maintenance Schedule to determine how
often to check the lubricant and when to change it. See
“Scheduled Maintenance Services” in the Index.
How to Check Lubricant
If the level is below the bottom of the filler plug hole,
you’ll need to add some lubricant. Add enough lubricant
to raise the level to the bottom
of the filler plug hole,
What to Use
Standard Differential
Use Axle Lubricant (GM Part No. 12345977) or SAE
80W-90 GL-5 gear lubricant.
Limited-Slip Differential
To add lubricant when the level is low, use Axle
Lubricant (GM
Part No. 12345977). To completely refill
after draining, add 4 ounces
(1 18 ml) of Limited-Slip
Differential Lubricant Additive (GM Part
No. 1052358).
Then fill to the bottom of the filler plug hole with Axle
Lubricant
(GM Part No. 12345977).
Engine Coolant
The cooling s stem in your vehicle is filled with new
DEX-COOL 8 engine coolant. This coolant is designed
to remain in your vehicle for
5 years or 150,000 miles
(240
000 km) whichever occurs first, if you add only
DEX-COOL’ extended life coolant.
The following explains your cooling system and how
to add coolant when it is low. If you have a problem
with engine overheating or if you need to add coolant
to your radiator, see “Engine Overheating” in the Index.
A
50150 mixture’ of water and DEX-COOL@
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.
e Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
Page 275 of 410

NOTICE:
When adding coolant, it is important that you
use only DEX-COOL@ (silicate-free) c’oolant.
If silicated coolant is added to the system,
premature engine, heater core
or radiator
corrosion may result. In addition, the engine
coolant will require change sooner
-- at
30,000 miles (50 000 km) or 24 months,
whichever
occurs first,
What to Use
Use a mixture of one-half ckan water (preferably
distilled)
and one-half DEX-COOL@ coolant which
won’t damage aluminum parts. If you use this mixture,
you don’t need to add anything else.
I
Adding only plain water to your cooling system
can be dangerous. Plain water, or
some other
liquid like alcohol, can boil before the proper coolant mix will.
Your vehicle’s coolant warning
system is set
for the proper coolant mix. With
plain water or the wrong mix, your engine could
get too hot but you wouldn’t get the overheat
warning. Your engine could catch fire and
you or
others could be burned. Use a 50J50 mix of clean
water and DEX-COOL’coolant.
6-30
Page 276 of 410
NOTICE:
If you use an improper coolant mix, your engine
could overheat and
be badly damaged. The
repair cost wouldn’t be covered by your
warranty. Too much water in the mix can freeze
and crack the engine, radiator, heater core and
other parts.
If you have to add coolant more than four times a year,
have your dealer check your cooling system.
NOTICE:
If you use the proper coolant, you don’t have to
add extra inhibitors or additives which claim to
improve the system.
These can be harmful.
Checking Coolant
When your engine is cold, check the dipstick on the cap
of the coolant recovery tank. The coolant level should
be at
COLD, or a little higher. When your engine is
warm, the level on the dipstick should be up to HOT, or
a little higher.
6-31
Page 277 of 410
5.7L Engine Only If
this light comes on,
it
means
you’re low on
engine coolant.
Adding Coolant to the Recovery Tank
If you need more coolant, add the proper DEX-COOL@
coolant mixture at the coolant recovery tank, but only
when your engine is cool. If the tank is very low or
empty, also add coolant to the radiator.
See “Engine
Overheating” in the Index
for information.
Turning the raalator 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,
Add coolant mixture at the recovery tank, but be careful
not to spill it.
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. Don’t spill coolant on a hot engine.
I
6-32