2003 GMC SAFARI engine

If there seems to be no leak, start the engine again.
The engine cooling fan speed should increase when idle
speed is doubled by pushing the accelerator pedal
down. If it doesn’t, your vehicle needs service. Turn off
the engine.
Notice:Engine damage from running your engine
without coolant isn’t covered by your warranty.
Notice:When adding coolant, it is important that
you use only DEX-COOL
®(silicate-free) coolant.
If coolant other than DEX-COOL®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 occursrst.
Damage caused by the use of coolant other
than DEX-COOL
®is not covered by your new vehicle
warranty.
How to Add Coolant to the Coolant
Recovery Tank
If you haven’t found a problem yet, but the coolant level
isn’t at the ADD mark, add a 50/50 mixture ofclean
drinkable water, and DEX-COOL
®engine coolant at the
coolant recovery tank. SeeEngine Coolant on
page 5-25for more information.
{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 wouldn’t get the overheat warning.
Your engine could catchre and you or others
could be burned. Use a 50/50 mixture of clean,
drinkable water and DEX-COOL
®coolant.
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.
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{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. Don’t spill coolant on a hot engine.When the coolant in the coolant recovery tank is at the
ADD mark, start your vehicle.
If the overheat warning continues, there’s one more
thing you can try. You can add the proper coolant
mixture directly to the radiator, but be sure the cooling
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
CAUTION: (Continued)
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2. Then keep turning the
pressure cap, but now
push down as you
turn it. Remove
the pressure cap.
3. Fill the radiator with the proper DEX-COOL
®
coolant mixture, up to the base of thefiller
neck. SeeEngine Coolant on page 5-25for more
information about the proper coolant mixture.
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4. Thenfill the coolant recovery tank to the ADD mark.
5. Put the cap back on the coolant recovery tank,
but leave the pressure cap off.6. Start the engine and let it run until you can feel the
upper radiator hose getting hot. Watch out for the
engine cooling fan.
7. By this time, the coolant level inside the radiator
filler neck may be lower. If the level is lower, add
more of the proper DEX-COOL
®coolant mixture
through thefiller neck until the level reaches
the base of thefiller neck.
Then replace the pressure cap. At any time during
this procedure if coolant begins toflow out of
thefiller neck, reinstall the pressure cap. Be sure
the arrow on the pressure cap lines up.
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Engine Fan Noise
This vehicle has a clutched engine cooling fan. When
the clutch is engaged, the fan spins faster to provide
more air to cool the engine. In most everyday driving
conditions, the clutch is not fully engaged. This improves
fuel economy and reduces fan noise. Under heavy
vehicle loading, trailer towing and/or high outside
temperatures, the fan speed increases when the clutch
engages. So you may hear an increase in fan noise.
This is normal and should not be mistaken as the
transmission slipping or making extra shifts. It is merely
the cooling system functioning properly. The fan will
slow down when additional cooling is not required and
the clutch disengages.
You may also hear this fan noise when you start the
engine. It will go away as the fan clutch disengages.
Power Steering Fluid
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When to Check Power Steering Fluid
It is not necessary to regularly check power steeringfluid
unless you suspect there is a leak in the system or
you hear an unusual noise. Afluid loss in this system
could indicate a problem. Have the system inspected
and repaired. SeeEngine Compartment Overview
on page 5-12for reservoir location.
How to Check Power Steering Fluid
Turn the key off, let the engine compartment cool down,
wipe the cap and the 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 thefluid level on the
dipstick.
The level should be at the FULL COLD mark. If
necessary, add only enoughfluid to bring the level up to
the mark.
What to Use
To determine what kind offluid to use, seePart D:
Recommended Fluids and Lubricants on page 6-34.
Always use the properfluid. Failure to use the proper
fluid can cause leaks and damage hoses and seals.
Windshield Washer Fluid
What to Use
When you need windshield washerfluid, be sure to read
the manufacturer’s instructions before use. If you will
be operating your vehicle in an area where the
temperature may fall below freezing, use afluid that has
sufficient protection against freezing.
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Adding Washer Fluid
Open the cap with the
washer symbol on it. Add
washerfluid until the
tank is full.Notice:When using concentrated washeruid, follow the
manufacturer’s instructions for adding water.
Don’t mix water with ready-to-use washeruid.
Water can cause the solution to freeze and
damage your washeruid tank and other parts of
the washer system. Also, water doesn’t clean as
well as washeruid.
Fill your washeruid tank only three-quarters full
when it’s very cold. This allows for expansion if
freezing occurs, which could damage the tank if
it is completely full.
Don’t use engine coolant (antifreeze) in your
windshield washer. It can damage your washer
system and paint.
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Brakes
Brake Fluid
Your brake master cylinder reservoir isfilled with DOT-3
brakefluid. SeeEngine Compartment Overview on
page 5-12for the location of the reservoir.
There are only two reasons why the brakefluid level in
the reservoir might go down. Thefirst is that the
brakefluid goes down to an acceptable level during
normal brake lining wear. When new linings are put in,
thefluid level goes back up. The other reason is
thatfluid is leaking out of the brake system.If it is, you should have your brake systemfixed, 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 brakefluid.
Adding brakefluid won’t correct a leak. If you addfluid
when your linings are worn, then you’ll have too
muchfluid when you get new brake linings. You should
add (or remove) brakefluid, as necessary, only when
work is done on the brake hydraulic system.
{CAUTION:
If you have too much brakeuid, it can spill on
the engine. Theuid will burn if the engine is
hot enough. You or others could be burned,
and your vehicle could be damaged. Add brake
uid only when work is done on the brake
hydraulic system. See“Checking Brake Fluid”
in this section.
Refer to the Maintenance Schedule to determine when
to check your brakefluid. SeePart C: Periodic
Maintenance Inspections on page 6-32.
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