cooling GMC ENVOY 1998 Owner's Manual

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
7-6 I
~ 1 I
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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
7-26
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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.
7-38
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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.
7-43
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GloveBox .................................... 2-42
Gross Axle Weight Rating ........................ 4-40
Gross Vehicle Weight Rating ...................... 4-40
Guide en Franpis
11 .. .................................
GVWR ....................................... 4-40
Halogen Bulbs
................................ 6-32
Hazard Warning Flashers
.......................... 5-2
Head Restraints
................................. 1-5
Headlamps .................................... 2-36
Bulb Replacement
............................ 6-32
HighLow Beam Changer
...................... 2-3 1
On Reminder ................................ 2-37
Hearing Impaired. Customer Assistance
.............. 8-4
Heated Front Seats
............................... 1-3
Heated Outside Rearview Mirror ................... 2-42
High Intensity Discharge Lighting
.................. 6-3 1
Highway Hypnosis .............................. 4-34
Hill and Mountain Roads
......................... 4-34
Hitches. Trailer
................................. 4-46
Hood
.......................................... 6-8
Horn ......................................... 2-29
Hydroplaning
.................................. 4-30
Heating
........................................ 3-5
Ignition Positions
.................................... 2-14
Transmission Lock Check
...................... 7-42
Ignition Transmission Lock Check
................. 7-42
Illuminated Entry
............................... 2-39
Inflation. Tire
............................. 6-37. 7-39 Inflator
. Accessory .............................. 2-50
Inspections
Brakesystem
................................ 7-44
Engine Cooling Systetn
........................ 7-43
Exhaust Systems
............................. 7-43
Front Drive Axle Boot Seal
..................... 7-43
Steering
.................................... 7-43
Suspension
.................................. 7-43
Throttle System
.............................. 7-44
Transfer
Case ................................ 7-44
Instrument Panel
............................... 2-58
Cleaning
.................................... 6-48
Cluster
..................................... 2-60
FuseBlock
.................................. 6-56
Interior Lamps ................................. 2-39
Jacking Equipment
............................. 5-24
Jump Starting
................................... 5-3
Key
in the Ignition ............................. 2-11
Key Lock Cylinders Service
...................... 7-40
Keyless Entry System
............................ 2-6
Keys
.......................................... 2-2
Labels
Certification/Tire
............................. 4-40
Fuse
.................................. 6.56. 6.58
Safety Belt
.................................. 1-53
Service Parts Identification ..................... 6-54
Vehicle Identification Number
................... 6-54
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