Page 188 of 376

Downloaded from www.Manualslib.com manuals search engine Driving On Grades
Reduce speed and shift to a lower gear before you start
down
a long or steep downgrade. If you don’t shift
down, you might have to use your brakes
so much that
they would get hot and
no longer work well.
On a long uphill grade, shift down and reduce
your
speed to around 45 mph (70 kdh) to reduce the
possibility
of engine and transmission overheating.
When towing at high altitude
on steep uphill grades,
consider the following: Engine coolant will boil
at a
lower temperature than at normal altitudes.
If you turn
your engine off immediately after towing at high altitude
on steep uphill grades, your vehicle may show signs
similar
to engine overheating. To avoid this, let the
engine run while parked (preferably on level ground)
with the automatic transmission
in PARK (P) for a few
minutes before turning the engine off. If you do get the
overheat warning, see “Engine Overheating”
in the Index.
Parking on Hills
You really should not park your vehicle, with a trailer
attached, on a hill. If something goes wrong, your rig
could start to move. People can be injured, and both
your vehicle and the trailer can be damaged.
But if you ever have to park your rig
on a hill, here’s
how to do it:
1. ’ Apply your regular brakes, but don’t shift into
PARK (P) yet. Then turn your wheels into the curb
if facing downhill or into traffic if facing uphill.
2. Have someone place chocks under the trailer wheels.
3. When the wheel chocks are in place, release the
regular brakes until the chocks absorb the load.
4. Re-apply the regular brakes. Then apply your
parking brake and then shift
to PARK (P).
5. Release the regular brakes.
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Page 204 of 376
Downloaded from www.Manualslib.com manuals search engine Cooling System
When you decide it’s safe to lift the hood, here’s what
you’ll see:
A. Radiator Pressure Cap
B. Coolant Recovery Tank
C. Engine Fan(s)
If the coolant inside the coolant recovery tank is boiling,
don’t
do anything else until it cools down.
The coolant level should be at
or above the FULL
COLD mark.
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.
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Page 205 of 376

Downloaded from www.Manualslib.com manuals search engine A CAUTION:
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, it could lose
all coolant. That could
cause an engine fire, and you could be burned.
Get any leak fixed before you drive the vehicle.
NOTICE:
Engine damage from running your engine
without coolant isn’t covered
by your warranty.
If there seems to be no leak, start the engine again. See
if the fan speed increases when idle speed is doubled by
pushing the accelerator pedal down.
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 the FULL COLD mark, add a 5060 mixture of
clean water (preferably distilled) and DEX-COOL’”
(orange-colored, silicate-free) antifreeze at the coolant
recovery tank. (See “Engine Coolant”
in the Index for
more information.)
Adding only plain water to your cooling sy,,,m
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 50/50 mix of clean
water and DEX=COOL
TM antifreeze.
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Page 210 of 376
Downloaded from www.Manualslib.com manuals search engine 5. Put the cap back on the coolant recovery tank, but
leave
the radiator pressure cap off.
I
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 may 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.
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Page 250 of 376
Downloaded from www.Manualslib.com manuals search engine 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, the coolant level should be at
FULL COLD, or a little higher.
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Page 252 of 376

Downloaded from www.Manualslib.com manuals search engine 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, 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
Refer to the Maintenance Schedule 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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Page 341 of 376

Downloaded from www.Manualslib.com manuals search engine I Long Tripmighway Maintenance Schedule I- Gasoline Engines
97,500 Miles (162 500 km)
0 Change engine oil and filter (or every
12 months, whichever occurs first).
An Ernissiorz Control Service.
0 Lubricate chassis components; see footnote ##
(or every 12 months, whichever occurs first).
0 Check axle fluid level and add fluid
as needed. *‘1:
0 Rotate tires. See “Tire Inspection and
Rotation”
in the Index for proper rotation
pattern and additional information. During
tire rotation, check brake calipers for
freedom of movement. Refer to the
appropriate
GM service manual for proper
caliper service procedures.
100,000 Miles (1 66 000 km)
0 Drain, flush and refill cooling system
(or every
60 months since last service,
whichever occurs first). See “Engine
Coolant’’
in the Index for what to use.
Inspect hoses. Clean radiator, condenser,
pressure cap and neck. Pressure test the
cooling system and pressure cap.
An Emission Control Service.
0 Inspect spark plug wires.
An Emission Control Service.
0 Replace spark plugs.
An Emission Control Service.
(Continued)
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Page 343 of 376

Downloaded from www.Manualslib.com manuals search engine Part B: Owner Checks and Services
Listed below are owner checks and services which
should be performed at the intervals specified to help
ensure
the safety, dependability and emission control
performance
of your vehicle.
Be sure any necessary repairs are completed at once.
Whenever any fluids or lubricants are added to your
vehicle, make sure
they are the proper ones, as shown
in Part
D.
At the First 100, 1,000 and 6,000 Miles
(160,1600 and 10 000 km)
For vehicles with dual wheels, check dual wheel nut
torque. For proper torque, see “Wheel Nut Torque” in
the Index.
At Each Fuel Fill
Engine Oil Level Check
Check the engine oil level and add the proper oil if
necessary. See “Engine Oil” in the Index .for
further details.
Engine Coolant Level Check
Check the engine coolant level and add the proper
coolant
mix if necessary. See “Engine Coolant” in the
Index for further details.
Windshield Washer Fluid Level Check
Check the windshield washer fluid level in the
windshield washer tank and add
the proper fluid if
necessary. See ”Windshield Waher Fluid” in the Index
for further details.
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