1998 GMC ENVOY overheating

Anti-Lock Brake System Warning Light
With the anti-lock brake
system, this light will come
on when you start your
engine and may stay
on
for several seconds.
That’s normal.
If the light stays on, or comes on when you’re driving,
your vehicle needs service. If the regular brake system
warning light isn’t on,
you still have brakes, but you
don’t have anti-lock brakes. If the regular brake system
warning light is
also on, you don’t have anti-lock brakes
and there’s a problem with your regular brakes. See
“Brake System Warning Light” earlier
in this section.
The anti-lock brake system warning light should come
on briefly when you turn the ignition key to RUN. If the
light doesn’t come on then, have it fixed
so it will be
ready to warn you
if there is a problem.
Engine Coolant Temperature Gage
This gage shows the engine
coolant temperature. If the
gage pointer moves into
the
red area, your engine is
too hot!
It means that your engine coolant has overheated. If you
have been operating your vehicle under normal driving
conditions,
you should pull off the road, stop your
vehicle and turn off
the engine as soon as possible.
The “Problems on the Road” section
of this manual
shows you what to do. See “Engine Overheating”
in
the Index.
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Driving On Grades
Reduce speed and shift to a 1owe.r gear Iwfow 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 km/h) to reduce the
possibility of engine and transmission overheating.
You should use DRIVE
(D) when towing a trailer.
Operating your vehicle
in DRIVE (D) when towing a
trailer
will minimize heat buildup and extend the life of
your transmission.
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 twn your
engine off imnlediately 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 (PI 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.
-. 3
3.
4.
5.
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.
Have someone place chocks under the trailer wheels.
When the wheel chocks are
in place, release the
regular brakes
until the chocks absorb the load.
Reapply the regular brakes. Then apply your parking
brake, and then shift into PARK
(P).
Release the regular brakes.
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Section 5 Problems on the Road
Here you’ll find what to do about some problems that can occur on the road.
5-2
5-2
5-3
5-7
5-11
Hazard Warning Flashers
Other Warning Devices
Jump Starting
Towing
Your Vehicle
Engine Overheating Engine
Fan Noise
If a Tire Goes Flat
Changing a Flat Tire
If You’re Stuck: In Sand, Mud,
Ice or Snow
5-20
5-20
5-2 1
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Engine Overheating
You will find a coolant temperature gage on your
vehicle's instrument panel. See "Gages" in the Index.
If Steam Is Coming From Your Engine
A CAUTION:
Steam from an overheated engine can burn you
badly, even if you ,just open the hood. Stay
away
from the engine if you see or hear steam coming
from
it. Just turn it off and get everyone away
from the vehicle until it cools down. Wait until
there is no sign of steam or coolant before you
open the hood.
If you keep driving when your engine is
overheated, the liquids in it can catch fire. You or
others could be badly burned. Stop your engine if
it overheats, and get out of the vehicle until the
engine is
cool.
NOTICE:
If your engine catches fire because you keep
driving with no coolant, your vehicle can be
badly damaged.
The costly repairs would not be
covered
by your warranty.
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Front 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 may need to add some lubricant. When
the differential is cold, add enough lubricant to
raise the level to
1/2 inch (12 mm) below the filler
plug hole.
When the differential
is at operating temperature
(warm), 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
The cooling s stem in your vehicle is filled with
DEX-COOL J 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, see “Engine Overheating” in
the Index.
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-
A CAUTION:
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 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.
A CAUTION:
I
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.
Radiator Pressure Cap
NOTICE:
Your radiator cap is a 15 psi (105 kPa)
pressure-type cap and must be tightly installed to
prevent coolant
loss and possible engine damage
from overheating. Be sure the arrows on the cap
line
up with the overflow tube on the radiator
filler neck.
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Poorly maintained and improperly used tires
are dangerous.
Overloading your tires can cause
overheating as
a result of too much friction.
You could have an air-out and
a serious
accident. See “Loading Your Vehicle” in
the Index.
Underinflated tires pose the same danger as
overloaded tires. The resulting accident
could cause serious injury. Check all tires
frequently to maintain the recommended
pressure. Tire pressure should be checked
when your tires are cold.
Overinflated tires are more likely to be cut,
punctured or broken by a sudden impact
--
such as when you hit a pothole. Keep tires
at the recommended pressure.
Worn, old tires can cause accidents. If your
tread is badly worn, or if your tires have
been damaged, replace them.
Inflation -- Tire Pressure
The CertificatiodTire label, which is on the driver’s
door edge, above the door latch, shows the correct
inflation pressures for your tires when they’re cold.
“Cold” means your vehicle has been sitting for at least
three hours or driven no more than
1 mile (1.6 km).
NOTICE:
Don’t let anyone tell you that underinflation or
overinflation is all right. It’s not.
If your tires
don’t have enough air (underinflation), you can
get the following:
Too much flexing
Too much heat
Tire overloading
Bad wear
Bad handling
Bad fuel economy.
NOTICE: (Continued)
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Engine (Continued) .............................. 6-9
Exhaust
..................................... 2-24
FanNoise
................................... 5-20
Identification
................................ 6-54
OilLevelCheck
.............................. 7-39
Overheating
................................. 5-11
Specifications
................................ 6-60
Engine Compartment Fuse Block
.................. 6-58
Engineoil
.................................... 6-10
Adding
..................................... 6-11
Additives
................................... 6-13
Checking
................................... 6-11
Kindtouse
................................. 6-12
Pressure Gage
................................ 2-69
Used
....................................... 6-14
When to Change
.............................. 6- I3
Exhaust, Engine
................................ 2-24
Exit Lighting
.................................. 2-39
Express-Down Window
.......................... 2-29
Fabric Cleaning
............................... 6-46
Filling
a Portable Fuel Container .................... 6-7
FillingYourTank
................................ 6-5
Fi 1 ter
Air
........................................ 6-14
Remote Oil .................................. 6- 14
Finish Care .................................... 6-5 1
Finish Damage ................................. 6-52
Running While
Parked
......................... 2-25
Starting
..................................... 2-15
Engine Coolant
................................. 6-2 1
FirstGear ..................................... 2-20
Flashers. Hazard Warning
......................... 5-2
Flat Tire. Changing
............................. 5-21
Fluids and Lubricants
............................ 7-4.5
FogLampSwitch ............................... 2-38
Foreign Countries. Fuel ........................... 6-5
Four-wheel Drive
......................... 2-26. 6-20
French Language Manual 11
FrontAxle .................................... 6-21
Front Reading Lamps
....................... 2.39. 2.43
Front Storage Area .............................. 2-45
FrontTowing
................................... 5-9
Filling a Portable Container
...................... 6-7
Filling Your Tank
.............................. 6-5
Foreign Countries .............................. 6-5
Engine Compartment
.......................... 6-58
Instrument Panel
............................. 6-56
Fuses and Circuit Breakers
....................... 6-55
Gages
.. ...........................
Front Turn Signal Lamp Bulb Replacement .......... 6-33
Fuel
.......................................... 6-3
Cage
....................................... 2-72
Fuse Block
Engine Coolant Temperature
.................... 2-66
Fuel
....................................... 2-72
Engine Oil Pressure ........................... 2-69
GasCap
....................................... 6-5
Gate A-jar Light ................................ 2-71
GAWR
....................................... 4-40
Gear
Positions ................................. 2-18
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