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Operating the engine with the air cleaner off
can cause you or others to be burned. The air
cleaner not only cleans the air, it stops flame
if
the engine backfires. If it isn’t there, and the
engine backfires,
you could be burned. Don’t
drive with
it off, and be careful working on the
engine with the air cleaner off.
NOTICE:
If the air cleaner is off, a backfire can cause a
damaging engine fire. And, dirt can easily get
into your engine, which will damage
it. Always
have the air cleaner in place when you’re driving.
~ 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
50,000 miles
(83 000 km) if the vehicle’s GVWR is over 8,600 or
if the vehicle is mainly driven under one or more of
these conditions:
In heavy city traffic where the outside temperature
regularly reaches
90°F (32°C) or higher.
In hilly or mountainous terrain.
When doing frequent trailer towing.
Uses such as found in taxi, police or delivery service.
If your vehicle’s
GVWR is not over 8,600 and you do
not use your vehicle under any of these conditions, the
fluid and filter do
not require changing.
See “Scheduled Maintenance Services” in the Index.
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How to Check
Because this operation can be a little difficult, you
may choose to have this done at your
GM dealership
Service Department.
If you do it yourself, be sure to follow all the instructions
here, or you could get a false reading on the dipstick.
NOTICE:
I
Too much or too little fluid can damage your
transmission.
Too much can mean that some of
the fluid could come out and fall on hot engine
parts or exhaust system parts, starting a fire. Be
sure to get an accurate reading if
you check your
transmission fluid.
Wait at least 30 minutes before checking the
transmission fluid level if you have been driving:
When outside temperatures are above 90°F (32°C).
0 At high speed for quite a while.
In heavy traffic -- especially in hot weather.
0 While pulling a trailer.
To get the right reading, the fluid should be at normal
operating temperature, which is
180°F to 200°F
(82°C to 93°C).
Checking Transmission Fluid Hot
Get the vehicle warmed up by driving about 15 miles
(24 km) when outside temperatures are above 50°F
(10°C). If it's colder than 50°F (lO"C), drive the
vehicle in
DRIVE (D) until the engine temperature gage
moves and then remains steady for
10 minutes. Then
follow the hot check procedures.
Checking Transmission Fluid Cold
A cold check is made after the vehicle has been sitting
for eight hours or more with the engine off and is used
only as a reference. Let the engine run at idle for five
minutes if outside temperatures are
50°F (10°C) or
more. If it's colder than
50°F (lO"C), you may have
to idle the engine longer. Should the fluid level be low
during a cold check, you
must perform a hot check
before adding fluid. This will give
you a more accurate
reading of the fluid level.
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Checking the Fluid Hot or Cold
Park your vehicle on a level place. Keep the
engine running.
With the parking brake applied, place the shift lever
a With your foot on the brake pedal, move the shift
in
PARK (P).
lever
through each gear range, pausing for about
three seconds in each range. Then, position the shift
lever in PARK
(P).
Let the engine run at idle for three minutes or more. Then, without shutting
off the engine, follow these steps:
1. Flip
the handle up and then pull out the dipstick and
wipe
it with a clean rag or paper towel.
2. Push it back in all the way, wait three seconds and
then pull it back
out again.
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Page 256 of 388

Rear Axle Engine Coolant
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
Refer to the Maintenance Schedule to determine what
kind of lubricant to use. See “Recommended Fluids and
Lubricants” in
the Index. The cooling
s stem in your vehicle
is filled with
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 sysre~ And how to
add coolant when it is low. If
you have a problem with
engine overheating,
see “Engine Overheating” in
the Index.
A 50/50 mixture of water and DEX-COOL’ coolant will:
0 Give freezing protection down to -34°F (-37°C).
0 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.
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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.
I NOTICE: I
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 yo bur engine is cold, the coolant level sho
FULL COLD, or a little higher. uld
be at
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Thermostat
Engine coolant temperature is controlled by a thermostat
in the engine cooling system. The thermostat stops the
flow of coolant through the radiator until the coolant
reaches a preset temperature.
When you replace your thermostat, an
AC@ thermostat
is recommended.
Power Steering Fluid
When to Check Power Steering Fluid
It is not necessary to regularly check power steering
fluid unless you suspect there
is a leak in the system or
you hear an unusual noise.
A fluid loss in this system
could indicate a problem. Have the system inspected
and repaired.
How To Check Power Steering Fluid
When the engine compartment is cool, wipe the cap and
top
of the reservoir clean, then unscrew the cap and
wipe the dipstick with a clean rag. Replace the cap and
completely tighten it. Then remove the cap again and
look at the fluid level
on the dipstick.
The level should be at the FULL COLD mark.
If
necessary, add only enough fluid to bring the level up
to the mark.
To prevent brake fluid contamination never check or fill
the power steering reservoir with the master cylinder
cover off.
What to Use
To determine what kind of fluid to use, see
“Recommended Fluids and Lubricants” in the Index.
Always use the proper fluid. Failure to use the proper
fluid can cause leaks and damage hoses and seals.
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Brakes
Brake Fluid
your brake system fixed, since a leak means that sooner
or later your brakes won’t work well, or won’t work
at all.
So, it isn’t a good idea to “top off’ your brake fluid.
Adding brake fluid won’t correct a leak.
If you add fluid
when your linings are worn, then you’ll have too much
fluid when you get new brake linings. You should add
(or remove) brake fluid, as necessary,
only when work is
dQne on the brake hydraulic system.
Your brake master cylinder reservoir is here. It is filled
with DOT-3 brake fluid.
There
are only two reasons why the brake fluid level in
the reservoir might go down. The first is that the brake
fluid
goes down to an acceptable level during normal
brake lining wear. When new linings are put in, the fluid
level goes back
up. The other reason is that fluid is
Zeaking out of the brake system. If it is, you should have
If you have too much brake fluid, it can spill
on the engine. The fluid will burn if the engine
is hot enough.
You or others could be burned,
and your vehicle could be damaged. Add brake
fluid only when work
is done on the brake
hydraulic system.
Refer to the Maintenance Schedule to determine when to
check your brake fluid. See “Periodic Maintenance
Inspections” in the Index.
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Engine Identification -- Gasoline Engines
Engine “VORTEC”4300 “VORTEC”5000
Type V6 V8
VIN Code
w M
Fuel System CSFI’ CSFI*
]Central
Sequential Fuel Injection
2Sequential Fuel Injection
Wheel Nut Torque
MODEL TORQUE
All 140 ft-lb (190 N-m)
Cooling System Capacity
ENGINE VIN
“VORTEC”4300
“VORTEC”5000
“VORTEC”5700
“VORTEC”7400 W
M
R
J
QTJ “VORTEC”5700
V8
R
CSFI’
1 Without Rear Heater*
11
Quarts (10.4 L)
17 Quarts (16 L)
17 Quarts (16 L)
23 Quarts (2 1.8 L)
“VORTEC”7400
V8
J
SF12
rl With Rear Heater 8
14 Quarts (13.2 L)
20 Quarts (18.9 L)
20 Quarts (18.9 L)
26 Quarts (24.6 L)
After refill, the level MUST be checked as outlined under “Engine Cooling System” in Section 5.
*All quantities are approximate.
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