1998 GMC ENVOY service interval

NOTICE: (Continued)
If your tires have too much air (overinflation),
you can get the following:
0 Unusual wear
Bad handling
Rough ride
Needless damage from road hazards.
When to Check
Check your tires once a month or more. Also, check the
tire pressure
of the spare tire.
How to Check
Use a good quality pocket-type gage to check tire
pressure. You can’t
tell if your tires are properly inflated
simply by looking at them. Radial tires may look
properly inflated even when they’re underinflated.
Be sure to put the valve caps back on the valve stems.
They help prevent leaks by keeping out dirt and moisture.
Tire Inspection and Rotation
Tires should be rotated every 6,000 to 8,000 miles
( 10 000 to 13 000 km). Any time you notice unusual
wear, rotate your tires
as soon as possible and check
wheel alignment.
Also check for damaged tires or
wheels. See “When It’s Time for New Tires” and
“Wheel Replacement” later in
this section for
more information.
The purpose of regular rotation is to achieve more
uniform wear for all tires on the vehicle. The first
rotation is the most important. See “Scheduled
Maintenance Services”
in the Index for scheduled
rotation intervals.
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Section 7 Maintenance Schedule
This section covers the maintenance required for your vehicle. Your vehicle needs these services to retain its safety,
dependability and emission control performance.
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7-4
7-5
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7-6
7-6 Introduction
Part
A: Scheduled Maintenance Services
Short Trip/City Definition
Short Trip/City Intervals
Long Trip/Highway Definition
Long Trip/Highway Intervals
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Short Trip/City Maintenance Schedule
Long Trip/Highway Maintenance Schedule
Part
B: Owner Checks and Services
Part
C: Periodic Maintenance Inspections
Part
D: Recommended Fluids and Lubricants
Part
E: Maintenance Record
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Maintenance Schedule
I Short Trip/City Definition I
Follow the Short TripKity Maintenance Schedule if any
one of these conditions is true for your vehicle:
Most trips are less than 5 to 10 miles (8 to 16 km).
This is particularly important when outside
temperatures are below freezing.
Most trips include extensive idling (such as frequent
driving in stop-and-go traffic).
off-road frequently.
You operate your vehicle in dusty areas 6r
0 You frequently tow a trailer or use a carrier on top of
your vehicle.
or other commercial application.
If the vehicle is used for delivery service, police, taxi
One
of the reasons you should follow this schedule if
you operate your vehicle under any of these conditions
is that these conditions cause engine oil
to break
down soonel:
Short Trip/City Intervals
Every 3,000 Miles (5 000 km): Engine Oil and Filter
Change (or
3 months, whichever occurs first). Chassis
Lubrication (or
3 months, whichever occurs first). Drive
Axle Service (or
3 months, whichever occurs first).
Every 6,000 Miles (10 000 km): Tire Rotation.
Every 15,000 Miles (25 000 km): Air Cleaner Filter
Inspection,
if driving in dusty conditions. Automatic
Transmission Service (severe conditions only).
Every 30,000 Miles (50 000 km): Air Cleaner Filter
Replacement. Fuel 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.
Every 100,000 Miles (166 000 km): Spark Plug Wire
Inspection. Spark Plug Replacement. Positive
Crankcase Ventilation (PCV) Valve Inspection.
(Continued)
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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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Short TripKity Maintenance Schedule I
The services shown in this schedule up to 100,000 miles
( 166 000 km) should be performed after 100,000 miles
( 166 000 km) at the same intervals. The services shown
at
150,000 miles (240 000 km) should be performed at
the same interval after 150,000 miles (240
000 ktn).
See “Owner Checks and Services” and “Periodic
Maintenance Inspections” following.
Footnotes
7 The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure
to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to the
completion
of the vehicle’s ~1sefu1 life. We, however.
urge that all recommended maintenance services be
performed
at the indicated intervals and the maintenance
be recorded.
## Lubricate the front suspension, ball joints, steering
linkage, parking brake cable guides, propshaft splines.
universal joints and brake pedal springs.
+ A ~ood time to check your brakes is during tire
rotation. See “Brake System Inspection” under ”Periodic
Maintenance Inspections”
in Part C of this schedule.
.:. .:, -,-*,- Drive axle service (see “Recommended Fluids and
Lubricants“ in the Index for proper lubricant to use):
Locking Differential -- Drain fluid and refill at first
engine oil change.
At subsequent oil changes. check
fluid level and add fluid
as needed. If driving in
dusty areas or towing a trailer, drain fluid and refill
every 15,000 miles
(25 000 km).
Standard Differential -- Check fluid level and add
fluid
as needed at every oil change. If driving in
dusty areas or towing a trailer. drain fluid and refill
every
15,000 miles (25 000 km).
More frequent lubrication may be required for
hea\jy-duty
or off-l-oad use.
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I Long Tripmighway Maintenance Schedule I
The services shown in this schedule up to 100,000 miles
(166 000 km) should be performed after 100,000 miles
( 166 000 km) at the same intervals. The services shown
at
150,000 miles (240 000 km) should be performed at
the same interval after 150,000 miles (240 000 km).
See “Owner Checks and Services” and “Periodic
Maintenance Inspections” following.
Footnotes
i- The U.S. Environmental Protection Agency or the
California Air Resources Board has determined that the
failure to perform this maintenance item will not nullify
the emission warranty or limit recall liability prior to the
completion
of the vehicle’s useful life. We, however,
urge that all recommended maintenance services be
performed at the indicated intervals and the maintenance
be recorded.
## Lubricate the front suspension, ball joints, steering
linkage and transfer case shift linkage, parking brake
cable guides, propshaft splines, universal joints and
brake pedal springs.
+ A good time to check your brakes is during tire
rotation. See ‘’Brake System Inspection’’ under “Periodic
Maintenance Inspections”
in Part C of this schedule.
:k:k Drive axle service (see “Recommended Fluids and
Lubricants”
in the Index for proper lubricant to use):
Locking Differential -- Drain fluid and refill at first
engine oil change. At subsequent oil changes, check
fluid level and add fluid
as needed.
fluid as needed at every engine
oil change.
Standard Differential -- Check fluid level and add
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Part B: Owner Checks an - Services Engine Coolant Level Check
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 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. Check
the engine coolant
level and add DEX-COOL'
coolant mixture
if necessary. See "Engine Coolant'' in
the Index for further details.
Windshield Washer Fluid Level Cl: -.
Check the windshield washer fluid level in the
windshield washer tank and add the proper fluid
if
necessary. See "Windshield Washer Fluid" in the Index
for further details.
At Least Once a Month
Tire Inflation Check
Make sure tires are inflated to the correct pressures. See
"Tires"
in the Index for further details.
Cassette Deck Service
Clean cassette deck. Cleaning should be done every
SO hours of tape play. See "Audio Systems" in the
Index for further details.
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Throttle System Inspection
Inspect the throttle system for interference or binding,
and for damaged or missing parts. Replace parts as
needed. Replace any components that have high effort
or excessive wear.
Do not lubricate accelerator and
cruise control cables.
Drive Axle Service
Check readfront axle fluid level and add as needed.
Check constant velocity joints and axle seals for leaking.
Transfer Case (Four-wheel Drive)
Inspection
Every 12 months or at oil change intervals, check front
axle and transfer case and add lubricant when necessary.
Check vent hose at transfer case for kinks and proper
installation. More frequent lubrication may be required
on off-road
use.
Brake System Inspection
Inspect the complete system. Inspect brake lines and
hoses for proper hook-up, binding, leaks, cracks,
chafing, etc. Inspect disc brake pads for wear and rotors
for surface condition. Inspect other brake parts,
including calipers, parking brake, etc. Check parking
brake adjustment. You may need to have your brakes
inspected more often if your driving habits or conditions
result in frequent braking.
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