
The coolant level should be at or above COLD. If it isn’t, you may have a
leak in the radiator hoses, heater hoses, radiator, water pump or somewhere
else in the cooling system.
CAUTION
A
Heater and radiator hoses, and other engine parts, can be very\
hot.
Don’t touch them. If you
do, you can be burned.
Don’t run the engine
if there is a leak. If you run the engine, 1‘ it coulc
lose all coolant. That could cause an engine fire, and you could
be
I burned. Get any leak fixed before you drive the vehicle.
I
If there seems to be no leak, check to see if the electric engine fan (if you
have one) is running. If the engine is overheating, the fan \
should be running.
If
it isn’t, your vehicle needs service.
Start the engine again to see
if the regular fan runs when the engine does.
If
it doesn’t, your vehicle needs service. Turn off the engine.
How to Add Coolant to the Coolant Recovery Tank
If you haven’t found a problem yet, but the coolant level \
isn’t at or above
COLD, add a 50150 mixture of clean water (preferably distilled) and a proper
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K2550
6. Start the engine and let it run until you can feel the upper radiator hose
getting hot. Watch out for the engine fan@).
7. By this time, the coolant level inside the radiator filler neck m\
ay be
lower.
If the level is lower, add more of the proper mix through the filler
neck until the level reaches the base
of the filler neck.
1
K2515
8. Then replace the pressure cap. Be sure the arrows on the pressure cap
line up like this.
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Service & Appearance Care
.
Here you will find information about the care of your vehicle . This section
begins with service and fuel information. and then it shows
how to check
important fluid and lubricant levels
. There is also technical information about
your vehicle. and a section devoted to its appearance care
.
Service ........................................................................\
........................................... 6-3
Fuel ........................................................................\
................................................ 6-4
Checking Things Under the Hood
....................................................................... \
6-8
Hood Release
........................................................................\
............................ 6-8
Engine Oil ........................................................................\
.................................. 6-9
Air Cleaner
........................................................................\
............................... 6-16
Automatic Transmission Fluid
........................................................................\
. 6-17
Manual Transmission Fluid ........................................................................\
..... 6-20
Hydraulic Clutch
........................................................................\
....................... 6-21
Transfer Case
........................................................................\
.......................... 6-23
Front
Axle ........................................................................\
................................. 6-24
Rear Axle
........................................................................\
................................. 6-24
Engine Coolant
........................................................................\
........................ 6-25
Power Steering Fluid
........................................................................\
............... 6-29
Windshield Washer Fluid
........................................................................\
......... 6-31
Brake Master Cylinder
........................................................................\
............. 6-32
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~AUTION
- Things that burn can get on hot engine parts and start a fire. These
include liquids like gasoline,
oil, coolant, brake fluid, windshield
washer and other fluids, and plastic or rubber.
You or others could
be burned. Be careful not to drop or spill things that will burn onto a
Before closing the hood, be sure
all the filler caps are on properly. Then just
pull the
hood down and close it firmly.
Engine Oil
It's a good idea to check your engine oil every time you get fuel. In order to
get an accurate reading, the
oil must be warm and the vehicle must be on
level ground.
Turn
off the engine and give the oil a few minutes to get back down into the
oil pan. If you don't, the oil dipstick might not show the actual level.
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How to Check Lubricant:
PO592
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.
Engine Coolant
I
PO593
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Service & Appearance Care
The following explains your cooling system and how to add cool\
ant when it is
low.
If you have a problem with engine overheating, see “Engine
Overheating” in the Index.
The proper coolant for your vehicle
will:
Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 258°F (125°C).
Protect against rust and corrosion.
Help keep the proper engine temperature.
Let the warning lights and gages work as they should.
What to Use:
Use a mixture of clean water (preferably distilled), and antifreeze that meets
“GM Specification
6038-M,” which won’t damage aluminum parts. Also use
GM Engine Coolant Supplement (sealer) with a complete coolant change.
If
you use these, you don’t need to add anything else.
Adding only plain water to your cooling system can be dangerous.
I
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. Us\
e
a 50/50 mix of clean water and a proper antifreeze.
jIi ,yo.w use an improper coolant mix, your engine .coutd overheat andi
badly damaged. The repair cost wouldn’t be covered by your warranty.’ TP~
much water in ;the mix can freeze and crack the engine, radiator, .heater
wre-ad -.other parts.
Some conditions, such as air trapped in the cooling system, can affect the
coolant level in the radiator. Check the coolant level when th\
e engine is cold
and follow the steps under “Adding Coolant” for the prope\
r way to
add
coolant.
.. .. ..
If you have to add coolant mdre than four times a year, have your dealer
check
your cooling system.
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k
NOTICE
f YOU use the proper coolant, you don’t have to add extra inhibitors or
idditives which claim to improve the system. These can be harmful
Adding Coolant
‘1 L
L
L
PO206
To Check Coolant: When your engine is cold, the coolant level should be at
COLD, or a little higher. When your engine is warm, the level shoul\
d be up
to HOT, or a little higher.
To Add Coolant: If you need more coolant, add the proper mix at the
coolant recovery tank.
I CAUTION
4
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
I cap-even a little-when the engine and radiator are hot. I
Add coolant mix at the recovery tank, but be careful not to spill it.
~ ~~
1 CAUTION I
You can be burned if you spill coolant on hot engine parts. Coolant
- b contains ethylene glycol, and it will burn if the engine parts are hot
I enough. Don’t spill coolant on a hot engine. I
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ProCarManuals.com

Scheduled Maintenance Services
Explanation Of Scheduled Maintenance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to use are listed in this section. Make sure
whoever services your vehicle uses these.
All parts should be replaced and
all necessary repairs done before you or anyone else drives the ve\
hicle.
1. ENGINE OIL AND OIL FILTER CHANGE* -ALWAYS USE SG OR
SG/CE QUALITY, ENERGY CONSERVING II OILS OF THE PROPER
VISCOSITY. To determine the preferred viscosity oil for your vehicle’s
engine (e.g. SAE 5W-30 or
10W-30), see “Engine Oil” in the Index.
2. CHASSIS LUBRICATION -Lubricate the front suspension, king pin
bushings, steering linkage, transmission, and transfer case shift\
linkage,
parking brake cable guides, propshaft splines
(2 wheel drive), brake
pedal springs, and clutch pedal springs at the intervals specif\
ied.
If you have a 3500 HD, lubricate the king pins and king pin bushings
every
1,500 miles (2500 km) for Maintenance Schedule 1, or every 3,000
(5000 km) for Maintenance Schedule 2.
Ball joints and king pin bushings should not be lubricated unl\
ess their
temperature is
10°F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication
or they could be damaged.
Also, be sure to check all the vehicle fluid levels at this time.
3.
CLUTCH FORK BALL STUD LUBRICATION -Lubricate the clutch fork
ball stud through the fitting on the clutch housing. Lubricant \
must be
added “sparingly” to the fitting, as only.
0066 Ib. (.003 kg) is required to
lubricate the ball stud surface. Do not add lubricant more often than the
intervals in the Maintenance Charts.
Too much lubricant will damage
the clutch
assembly.
4. ENGINE IDLE SPEED ADJUSTMENT (DIESEL ENGINES)* -Adjust to
the specifications shown on the underhood label. You must use
calibrated test equipment.
5. COOLING SYSTEM SERVICE* -Drain, flush and refill system with new
coolant. See “Engine Coolant” in the Index for the proper\
coolant and
mixture
to use in your vehicle.
Also inspect the hoses and replace them if they i cracked, swollen, or
deteriorated. Tighten all hose clamps (except consrant tension clamps).
Remove debris and clean the outside of the radiator and air c\
onditioning
condenser. Wash the radiator neck.
To ensure proper operation, pressure
test the radiator and cap.
* An Emission Control Service
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