1998 GMC ENVOY service

JTION:
A vehicle can fall from a car carrier if it isn’t
adequately secured. This can cause
a collision,
serious personal injury and vehicle damage. The
vehicle should be tightly secured with chains or
steel cables before it is transported.
Don’t use substitutes (ropes, leather straps,
canvas webbing, etc.) that can be cut by sharp
edges underneath the towed vehicle. Always use
T-hooks inserted in the T-hook slots. Never use
J-hooks. They will damage drivetrain and
suspension components.
When your vehicle is being towed, have the ignition key
turned
to the OFF position. The steering wheel should
be clamped
in a straight-ahead position with a clamping
device designed for towing service.
Do not use the
vehicle’s steering column lock for this. The transmission
should be in NEUTRAL
(N) and the transfer case
should be
in 2HI. The parking brake should be released.
If your vehicle has no electrical power, the electrical
solenoid lock
must be overridden to shift from
PARK (P) to NEUTRAL (N). Follow these steps:
1 I Remove the wood trim panel surrounding the base
2. Reach inside the console and find the white of the shift lever.
solenoid lever.
(ii
3. Push the solenoid
lever down.
4. While holding the solenoid lever in the unlock
position, press the shift lever button and shift into
NEUTRAL
(N).
5. Release the solenoid lever and replace the trim panel.
Don’t have your vehicle towed on the drive wheels
unless
you must. If the vehicle must be towed on the
drive wheels, be sure to follow the speed and distance
restrictions later
in this section or your transmission will
be damaged. If these limitations must be exceeded, then
the drive wheels have to be supported
on a dolly.
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io Stea 5 Coming From Your Engine
~i you get the overheat warning but see or hear no
steam, the problem may not be too serious. Sometimes
the engine can get
a little too hot when you:
0 Climb a long hill on a hot day.
Stop after high-speed driving.
Idle for long periods in traffic.
Tow a trailer. See “Driving on Grades” in the Index.
If you get the overheat.warning with no sign of steam,
try this for a minute or
so:
1. Turn off your air conditioner.
2. Turn on your heater to full hot at the highest fan
speed and open the window
as necessary.
3. If you’re in a traffic jam, shift to NEUTRAL (N);
otherwise, shift to the highest gear while
driving
-- DRIVE (D) or THIRD (3).
If you no longer have the overheat warning, you can
drive. Just to be safe, drive slower for about
10 minutes.
If the warning doesn’t come back on, you can
drive normally.
If the warning continues, pull over, stop, and park your
vehicle right away.
If there’s still no sign of steam, push the accelerator until
the engine speed is about twice as fast as normal idle
speed. Bring the engine speed back to normal idle speed
after two or three minutes.
Now see if the warning stops.
But then, if you still have the warning, turn ojfthe
engine nnd
get everyone out of the vehicle until it
cools down.
You may decide not to lift the hood but to get service
help right away.
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1 h 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: I
Engine damage from running your engine
without coolant isn’t covered by your
1 warranty.
If there seems to be no leak, start the engine again. See
if the engine cooling 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 ADD mark, add a 50/50 mixture of clean
brater (preferably distilled) and DEX-COOL@ engine
coolant at the coolant recovery tank. (See “Engine
Coolant”
in the Index for more information.)
Adding only plain water to your cooling system
can be dangerous. Plain water, or some other
liquid like 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
catch fire and you or others could be burned.
Use a
50/50 mixture of clean water and
DEX-COOL@ coolant.
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Section 6 Service and 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 part devoted
to its appearance care.
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Service
Fuel
Fuels in Foreign Countries
Filling Your Tank
Filling a Portable
Fuel Container
Checking Things Under the Hood
Engine Oil
Air Cleaner
Automatic Transmission Fluid
Rear Axle
Four- Wheel Drive
Engine Coolant
Radiator Pressure Cap
Thermostat
Power Steering Fluid
Windshield Washer Fluid
Brakes Battery
Bulb Replacement
Windshield Wiper Blade Replacement
Tires
Appearance Care
Cleaning the Inside
of Your Vehicle
Care of Safety Belts
Cleaning the Outside of Your Vehicle
Appearance Care Materials Chart
Vehicle Identification Number (VIN)
Service Parts Identification Label
Electrical System
Replacement Bulbs
Capacities and Specifications
Air Conditioning Refrigerants
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Service
Your dealer knows your vehicle best and wants you to
be happy with it. We hope you’ll go to your dealer for
all your service needs. You’ll get genuine
GM parts and
GM-trained and supported service people.
We hope you’ll want to keep your GM vehicle all GM.
Genuine GM parts have one of these marks:
A=----=- %
Genuine
Doing Your Own Service Work
If you want to do some of your own service work, you’ll
want to use the proper GM Service Manual. It tells you
much more about how to service your vehicle than this
manual can.
To order the proper service manual, see
“Service and Owner Publications” in the Index.
Your vehicle has an air bag system. Before attempting to
do your own service work, see “Servicing Your Air
Bag-Equipped Vehicle”
in the Index.
You should keep
a record with all parts receipts and list
the mileage and the date
of any service work you
perform. See “Maintenance Record” in the Index.
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You can be injured and your vehicle could be
damaged if you try to do service work on
a
vehicle without knowing enough about it.
0 Be sure you have sufficient knowledge,
experience, the proper replacement parts
and tools before you attempt any vehicle
maintenance task.
0 Be sure to use the proper nuts, bolts and
other fasteners. “English” and “metric”
fasteners can be easily confused.
If you use
the wrong fasteners, parts can later break
or
fall off. You could be hurt.
Adding Equipment to the Outside of
Your Vehicle
Things you might add to the outside of your vehicle can
affect the airflow around
it. This may cause wind noise
and affect windshield washer performance. Check with
your dealer before adding equipment to the outside of
your vehicle.
Fuel
Use regular unleaded gasoline rated at 87 octane or
higher. At a minimum,
it should meet specifications
ASTM D48 14
in the United States and CGSB 3.5-M93
in Canada. Improved gasoline specifications have been
developed by the American Automobile Manufacturers
Association (AAMA) for better vehicle performance
and engine protection. Gasolines meeting the AAMA
specification could provide improved driveability and
emission control system protection compared
to
other gasolines.
Be SUI-e the posted octane is at least 87. If the octane
is
less than 87, you may get a heavy knocking noise when
you drive. If it’s bad enough, it can damage your engine.
If you’re using fuel rated at 87 octane or higher and you
hear heavy knocking, your engine needs service. But
don‘t worry
if you hear a little pinging noise when
you’re accelerating or driving
LIP a hill. That‘s normal,
and you don‘t have
to buy a higher octane fuel to get rid
of pinging. It‘s the heavy, constant knock that means
you have a problem.
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If your vehicle is certified to meet California Emission
Standards (indicated on the underhood emission control
label),
it is designed to operate on fuels that meet
California specifications. If such fuels are not available
in states adopting California emissions standards, your
vehicle will operate satisfactorily
on fuels meeting
federal specifications,
but emission control system
performance may be affected. The malfunction indicator
lamp
on your instrument panel may turn on and/or your
vehicle may fail a smog-check test.
If this occurs, return
to your authorized
GM dealer for diagnosis to determine
the cause of failure. In the event it is determined that the
cause of the condition is
the type of fuels used, repairs
may not be covered by your warranty.
Some gasolines that are
not reformulated for low
emissions contain an octane-enhancing additive called
methylcyclopentadienyl manganese tricarbonyl (MMT);
ask your service station operator whether or not his fuel
contains MMT. General Motors does
not recommend the
use of such gasolines. If fuels containing MMT are used,
spark plug life may be reduced and your emission
control system performance may be affected. The
malfunction indicator lamp on your instrument panel
may turn
on. If this occurs, return to your authorized
GM dealer for service.
To provide cleaner air, all gasolines in the United States
are now required to contain additives that will help
prevent deposits from forming
in your engine and fuel
system, allowing your emission control system to
function properly. Therefore, you should not have to add
anything to
the fuel. In addition, gasolines containing
oxygenates, such as ethers and ethanol, and
reformulated gasolines may be available in your area
to
help clean the air. General Motors recommends that you
use these gasolines
if they comply with the
specifications described earlier.
I NOTICE:
Your vehicle was not designed for fuel that
contains methanol. Don’t use it.
It can corrode
metal parts in your fuel system and also damage
plastic and rubber parts. That damage wouldn’t be covered under your warranty.
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As shown in the chart, SAE SW-30 is best for your
vehicle. However, you can use
SAE low-30 if it’s going
to be 0°F (- 18°C) or above. These numbers on an oil
container show its viscosity, or thickness. Do
not use
other viscosity oils, such
as SAE 20W-SO.
NOTICE:
Use only engine oil with the American Petroleum
Institute Certified For Gasoline Engines
“Starburst”
symbol. Failure to use the
recommended oil can result in engine damage not
covered by your warranty.
GM Goodwrench@ oil meets all the requirements for
your vehicle.
If you are in an area where the temperature falls below
-20°F (-29”C), consider using either an SAE 5W-30
synthetic oil or an SAE OW-30 oil. Both will provide
easier cold starting and better protection for your engine
at extremely low temperatures.
Engine Oil Additives
Don’t add anything to your oil. Your dealer is ready to
advise if you think something should be added.
When to Change Engine Oil
If any one of these is true for you, use the short tripkity
maintenance schedule:
0 Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
driving
in stop-and-go traffic).
off-road frequently. your vehicle.
or other commercial application.
0 Most trips include extensive idling (such as frequent
0 You operate your vehicle in dusty areas or
0 You frequently tow a trailer or use a carrier on top of
0 The vehicle is used for delivery service, police, taxi
Driving under these conditions causes engine oil
to
break down sooner. If any one of these is true for your
vehicle, then you need to change your
oil and filter
every
3,000 miles (5 000 km) or 3 months -- whichever
occurs first.
If none of them is true, use the long trip/highway
maintenance schedule. Change the oil and filter every
7,500 miles (12 500 km) or 12 months -- whichever
occurs first. Driving
a vehicle with a fully warmed
engine under highway conditions causes engine oil
to
break down slower.
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