service GMC ENVOY 1998 Workshop Manual

Treadwear Temperature -- A, B, C
The
treadwear grade is a comparative rating based on
the wear rate of the tire when tested under controlled
conditions
on a specified government test course. For
example,
a tire graded 150 would wear one and a half
(1 1/2) times as well on the government course as a tire
graded
100. The relative performance of tires depends
upon the actual conditions
of their use, however, and
may depart significantly from the norm due to variations
in driving habits, service practices and differences in
road characteristics and climate.
Traction -- A, B, C
The traction grades, from highest to lowest, are A, B,
and C, and they represent the tire’s ability to stop on
wet pavement
as measured under controlled conditions
on specified government test surfaces
of asphalt and
concrete.
A tire marked C may have poor
traction performance.
Warning: The traction grade assigned to this tire is based
on braking (straight ahead) traction tests and does not
include cornering (turning) traction. The
temperature grades are
A (the highest), B, and C,
representing the tire’s resistance to the generation of
heat and its ability to dissipate heat when tested under
controlled conditions on
a specified indoor laboratory
test wheel. Sustained high temperature can cause the
material of the tire to degenerate and reduce tire life,
and excessive temperature can lead to sudden
tire
failure. The grade C corresponds to a level of
performance which all passenger car tires must meet
under the Federal Motor Vehicle Safety Standard
No. 109. Grades B and A represent higher levels of
performance on the laboratory test wheel than the
minimum required by law.
Warning: The temperature grade for this tire is
established for a tire that is properly inflated and not
overloaded. Excessive speed, underinflation, or
excessive loading, either separately or in combination,
can cause heat buildup and possible tire failure.
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Finish Damage
Any stone chips, fractures or deep scratches in the finish
should be repaired right away. Bare metal will corrode
quickly and may develop into a major repair expense.
Minor chips and scratches can be repaired with touch-up
materials available from your dealer or other service
outlets. Larger areas
of finish damage can be corrected
in your dealer’s body and paint shop.
Underbody Maintenance
Chemicals used for ice and snow removal and dust
control can collect on the underbody.
If these are not
removed, accelerated corrosion (rust) can occur
on
the underbody parts such as fuel lines, frame, floor
pan and exhaust system even though they have
corrosion protection.
At least every spring, flush these materials from the underbody with plain water. Clean any areas where mud
and other debris can collect. Dirt packed in closed areas
of the frame should be loosened before being flushed.
Your dealer or an underbody car washing system can do
this for you.
Chemical Paint Spotting
Some weather and atmospheric conditions can create
a chemical fallout. Airborne pollutants can fall upon
and attack painted surfaces on your vehicle. This
damage can take two forms: blotchy, ringlet-shaped
discolorations, and small irregular dark spots etched into
the paint surface.
Although no defect in the paint job causes this,
GMC
will repair, at no charge to the owner, the surfaces of
new vehicles damaged by this fallout condition within
12 months or 12,000 miles (20 000 km) of purchase,
whichever occurs first.
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Vehicle Identification Number (VIN)
Gl SAMPLE4UXWM072675 Gl
This is the legal identifier for your vehicle. It appears on
a plate in the front corner of the instrument panel, on the
driver’s side. You can see it
if you look through the
windshield from outside your vehicle. The
VIN also
appears on the Vehicle Certification and Service Parts
labels and the certificates
of title and registration.
Engine Identification
The 8th character in your VIN is the engine code. This
code will help you identify your engine, specifications
and replacement parts.
Service Parts Identification Label
You‘ll find this label on the inside of the glove box. It’s
very helpful if you ever need to order parts. On this
label
is:
0 your VIN,
0 the model designation,
0 paint information and
0 a list of all production options and
special equipment.
Be sure that
this label is not removed from the vehicle.
Electrical System
Add-on Electrical Equipment
NOTICE:
Don’t add anything electrical to your vehicle
unless you check with
your dealer first. Some
electrical equipment can damage your vehicle
and the damage wouldn’t be covered by your
warranty. Some add-on electrical equipment
can keep other components from working as
they should.
Your vehicle has an air bag system. Before attempting to
add anything electrical to your vehicle, see “Servicing
Your
Air Bag-Equipped Vehicle” in the Index.
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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.
7-2
7-4
7-5
7-5
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
7-7
7-27
7-39
7-43
7-45
7-47
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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I I M PORTANT:
KEEP ENGINE OIL
I
AT THE PROPER
LEVEL AND CHANGE AS
RECOMMENDED
Protection
Plan
Introduction
Your Vehicle and the Environment
Proper vehicle maintenance not only helps to keep your
vehicle
in good working condition, but also helps the
environment. All recornmended maintenance procedures
are inymrtant. Improper vehicle maintenance can even
affect the quality
of the air we breathe. Improper fluid
levels or the wrong tire inflation can increase the level
of emissions fro111 your vehicle. To help protect OLI~
environment. and to keep your vehicle in good
condition, please maintain your vehicle properly.
How This Section is Organized
The remainder of this section is divided into five parts:
“Part A: Scheduled Maintenance Services” shows
what to have done and
how often. Some of these
services can be complex,
so unless you are technically
qualified and have
the necessary equipment, you should
let your dealer‘s service department
or another qualified
service center
do these jobs.
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A
A CAUTION:
Performing maintenance work on a vehicle can
be dangerous. In trying to do some .jobs, you can
be seriously injured.
Do your own maintenance
work only
if you have the required know-how
and the proper tools and equipment for the job.
If you have any doubt, have a qualified
technician do the
work.
If you are skilled enough to do some work on your
vehicle, you will probably want to get the service
information. See “Service and Owner Publications“
in
the Index. “Part
B: Owner Checks and Services”
tells you what
should be checked and when.
It also explains what you
can easily do to help keep your \:chicle in good condition.
“Part C: Periodic Maintenance Inspections” explains
important inspections that
YOLK dealer’s service department
or another qualified service center should perform.
“Part
D: Recommended Fluids and Lubricants” lists
so~ne recommended products to help keep
your vehicle
properly maintained. These products. or their
equivalents, should be used whether you
do the work
yourself
or have it done.
“Part
E: Maintenance Record” provides a place for
you to ~-eco~-d the maintenance performed on your
vehicle. Whenever any maintenance is performed, be
sure to write
it down in this part. This will help you
determine when your next maintenance should be done.
In addition. it is a good idea to keep your maintenance
receipts. They may be needed to qualify your vehicle for
warranty repairs.
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Part A: Scheduled Maintenance
Services
Using Your Maintenance Schedule
We at General Motors want to help you keep your
vehicle in good working condition. But we don’t
know
exactly how you’ll drive it. You may drive very short
distances
only a few times a week. Or you may drive
long distances all the time in very hot, dusty weather.
You may use
your vehicle in making deliveries. Or
you may drive
it to work, to do errands or in many
other ways.
Because
of all the different ways people use their
vehicles, maintenance needs vary. You may even need
more frequent checks and replacements than you’ll find
in the schedules in this section. So please read this
section and
note how you drive. If you have any
questions
on how to keep your vehicle in good
condition, see your dealer.
This part tells you the maintenance services you should
have done and
when you should schedule them. If you
go to your dealer for your service needs, you’ll know
that GM-trained and supported service people will
perform the work using genuine GM parts. The proper fluids and lubricants to use are listed in
Part D. Make sure whoever services your vehicle uses
these. All parts should be replaced and all necessary
repairs done before you or anyone else drives the vehicle.
These schedules are for vehicles that:
0 carry passengers and cargo within recommended
limits. You will find these limits on your vehicle’s
Certificationflire label. See “Loading Your Vehicle”
in the Index.
0 are driven on reasonable road surfaces within legal
driving limits.
are driven off-road in the recommended manner. See
“Off-Road Driving With Your Four-Wheel-Drive
Vehicle”
in the Index.
0 use the recommended fuel. See “Fuel” in the Index.
Selecting the Right Schedule
First you’ll need to decide which of the two schedules is
right for your vehicle. Here’s how to decide which
schedule to follow:
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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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