1998 GMC ENVOY cooling

A 50/50 mixture of water and DEX-COOL@ coolant will:
0 Give freezing protection down to -34°F (-37°C).
Give boiling protection up to 265 “F ( 129°C).
0 Protect against rust and corrosion.
0 Help keep the proper engine temperature.
Let the warning lights and gages work as
they should.
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
0- at
30,000 miles (50 000 km) or 24 months,
whichever occurs
first. Damage caused by the use
of coolant other than DEX-COOL@ is not
covered by your new vehicle warranty.
What to Use
Use a mixture of one-half clean water (preferably
distilled) and one-half
DEX-COOL@ coolant which
won’t damage aluminum
parts. If you use this mixture,
you don’t need to add anything else.
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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NOTICE:
If you use an improper coolant mixture, your
engine could overheat and be badly damaged.
The repair cost wouldn’t be covered by your
warranty.
Too much water in the mixture 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
ADD, or a little higher. When your engine is warm, the
level should be up to
FULL HOT, or a little higher.
Adding Coolant
If you need more coolant, add the proper DEX-COOL@
coolant mixture at the cwolarzt recovery tank.
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NOTICE:
The wrong wheel can also cause problems with
bearing life, brake cooling, speedometer or
odometer calibration, headlamp aim, bumper
height, vehicle ground clearance and tire
clearance to the body and chassis.
See “Changing a Flat Tire” in the Index for
more information.
Used Replacement Wheels
I
Putting a used wheel on your vehicle is
dangerous. You can’t know how it’s been used or
how far it’s been driven. It could fail suddenly
and cause an accident.
If you have to replace a
wheel, use a new GM original equipment wheel.
Tire Chains
NOTICE:
Don’t use tire chains. They can damage your
vehicle because there’s not enough clearance.
Use another type of traction device only if its
manufacturer recommends it for use on your
vehicle and tire size combination and road
conditions. Follow that manufacturer’s
instructions.
To help avoid damage to your
vehicle, drive slowly, readjust
or remove the
device
if it’s contacting your vehicle, and don’t
spin your wheels.
If you do find traction devices that will fit, install
them on the rear tires.
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Normal Maintenance Replacement Parts
Replacement part numbers listed in this section are
based on the latest information available at the time of
printing, and are subject
to change. If a part listed in this
manual is not the same as the part used in your vehicle
when it was built, or if you have any questions, please
contact your GMC dealer.
Thermostat
......................... 1255905 1
Oil Filter ............................... PF52
Air Cleaner Filter
...................... A1 163C
PCV Valve
.......................... CV746C
Automatic Transmission Filter Kit
...... 24200796
Spark Plugs
.......................... .41-932
Fuel Filter
............................. GF48 1
Front Windshield Wiper Blade
................ Trico (20 inched50.8 cm)
Backglass Wiper Blade . . Trico (14 inched35.6 cm)
Capacities (Approximate)
Cooling System* ............. 11.7 quarts (1 1.1 L)
Crankcase* ................... 4.5 quarts (4.3 L)
Automatic Transmission
(Drain and Refill)*
........... 5.0 quarts (4.7 L)
Differential Fluid ............................
Front ....................... 2.6 pints (1.2 L)
Rear ........................ 4.0 pints ( 1.9 L)
Fuel Tank ..................... 18 gallons (68 L)
A/C Refrigerant ........... 30 oz. or 2 lbs. (0.9 kg)
of R- 134a
*After refill, the level
must be checked.
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Maintenance Schedule
I Short Trip/City Intervals I
Every 150,000 Miles (240 000 km): Cooling System
These intervals only summarize maintenance services.
Be sure to follow the complete maintenance schedule on
the following pages. Service
(or every
60 months, whichever occurs first).
1 Long TridHiEhwav Definition
Follow this maintenance schedule only if none of the
conditions from the Short Trip/City Maintenance
Schedule is true. Do not use this schedule
if the vehicle
is used for trailer towing, driven in a dusty area or used
off paved roads. Use the Short TripKity schedule for
these conditions.
Driving a vehicle with a fully warmed engine under
highway conditions causes engine oil
to break
down slower:
Long TridHiehwav Intervals
Every 7,500 Miles (12 500 km): Engine Oil and Filter
Change (or every 12 months, whichever occurs first).
Chassis Lubrication (or every 12 months, whichever
occurs first). Drive Axle Service. Tire Rotation.
Every 15,000 Miles (25 000 km): Automatic
Transmission Service (severe conditions only).
Every 30,000 Miles (50 000 km): Fuel Filter
Replacement. Air Cleaner Filter Replacement.
Every 50,000 Miles (83 000 km): Automatic
Transmission Service (normal conditions).
Every 60,000 Miles (100 000 km): Engine
Accessory Drive Belt Inspection. Fuel Tank, Cap and
Lines Inspection.
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
Every 150,000 Miles (240 000 km): Cooling System
Service (or every
60 months, whichever occurs first).
These intervals only summarize maintenance services.
Be sure to follow the complete maintenance schedule
on
the following pages.
Every 100,000 Miles (166 000 km): Spark Plug Wire
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I Short Trip/City Maintenance Schedule I
100,000 Miles (I66 000 km)
17 Inspect spark plug wires.
0 Replace spark plugs.
0 If you haven’t used your vehicle under severe service conditions listed
AFI Emission Control Service.
An Emission Control Service.
previously and, therefore, haven’t changed your autornatic transmission fluid,
change both the fluid and filter.
An Errzission Cmtd Service.
0 Inspect Positive Crankcase Ventilation (PCV) valve.
150,000 Miles (240 000 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
cooling system and pressure cap.
An Ernission Control Service.
DATE I
DATE I
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Long Tripmighway Maintenance Schedule
100,000 Miles (166 000 km)
0 Inspect spark plug wires.
0 Replace spark plugs.
0 If you haven't used your vehicle under severe service conditions listed
An Emission Control Service.
API Emission Control Service.
previously and, therefore, haven't changed your automatic transmission fluid,
change both the fluid and filter.
An Emission Control Service.
Inspect Positive Crankcase Ventilation (PCV) valve.
150,000 Miles (240 000 km)
0 Drain, flush and refill cooling system (or every 60 mon .ths since last service,
whichever occurs first)."'See "Engine Coolant"
in the Index for what to use.
DATE
DATE
MILEAGE
ACTUAL SERVICED BY
Inspect hoses. Clean radiator, condenser, pressure cap and neck. Pressure test I I
the cooling system and pressure cap.
An Emission Corztrol Service.
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Part C: Periodic Maintenance
Inspections
Listed below are inspections and services which should
be performed at least twice
a year (for instance, each
spring and fall).
You should let your dealer S service
department
or other qualified service center do these
jobs. Make sure any necessary repairs are completed
at once.
Proper procedures to perform these services may be
found in
a service manual. See “Service and Owner
Publications” in the Index.
Steering, Suspension and Front Drive Axle
Boot and Seal Inspection
Inspect the front and rear suspension and steering
system for damaged, loose or missing parts, signs of
wear or lack of lubrication. Inspect the power steering
lines and hoses for proper hook-up, binding, leaks,
cracks, chafing, etc. Clean and then inspect the drive
axle boot seals for damage, tears or leakage. Replace
seals if necessary.
Exhaust System Inspection
Inspect the complete exhaust system. Inspect the body
near the exhaust system.
Look for broken, damaged,
missing or out-of-position parts
as well as open seams,
holes, loose connections or other conditions which could
cause a heat build-up in the floor pan or could let
exhaust fumes into the vehicle. See “Engine Exhaust’’ in
the Index.
Engine Cooling System Inspection
Inspect the hoses and have them replaced if they are
cracked, swollen or deteriorated. Inspect all pipes,
fittings
and clamps; replace as needed. Clean the outside
of the radiator and air conditioning condenser.
To help
ensure proper operation,
a pressure test of the cooling
system and pressure cap is recommended at least
once a year.
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