air suspension GMC ENVOY 1998 Owners Manual

Payload
The payload capacity is shown on the CertificationRire
label. This is the maximum load capacity that your
vehicle can carry. Be sure to include the weight of the
occupants as part
of your load. If you added any
accessories or equipment after your vehicle left the
factory, remember to subtract the weight
of these things
from the payload.
Your dealer can help you with this.
Electronic Level Control
The rear of the vehicle is automatically kept level as you
load
or unload your vehicle. However, you should still
not exceed the
GVWR or the GAWR.
The ignition has to be on for the level control to work.
The system includes a small electric air compressor and
air-adjustable rear shock absorbers.
You may hear the compressor operating when you load
or unload your vehicle, and periodically
as the system
self-adjusts. This is normal. The compressor should operate for
brief periods
of time
If the sound continues for an extended period of time,
your vehicle needs service.
To keep your battery from
being drained. you may want to remove the
LD LEV
fuse in the fuse control panel until you can get your
vehicle serviced (see “Fuses and Circuit Breakers”
in
the Index).
Using heavier suspension components to get added
durability might not change your weight ratings.
Ask
your dealer to help you load your vehicle the right way.
NOTICE:
Your warranty does not cover parts or
components that fail because
of overloading.
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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.
7-7
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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
7-27
1
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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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1998 GMC SERVICE PUBLICATIONS ORDERING INFORMATION
The following publications covering the operation and servicing of your vehicle can be purchased by filling
the Service Publication Order Form in this book and mailing it in with your check, money order,
or credit card information to Helm, Incorporated (address below.)
CURRENT PUBLICATIONS FOR 1998 GMC
SERVICE MANUALS
Service Manuals have the diagnosis and repair information
on engines, transmission, axle, suspension, brakes,
electrical, steering, body, etc.
RETAIL SELL PRICE: $90.00
TRANSMISSION, TRANSAXLE, TRANSFER CASE
UNIT REPAIR MANUAL
This manual provides information on unit repair service
procedures, adjustments and specifications for the
1998 GM transmissions, transaxles and transfer cases.
RETAIL SELL PRICE:
$40.00
SERVICE BULLETINS
Service Bulletins give technical service information needed
to knowledgeably service General Motors cars and trucks.
Each bulletin contains instructions to assist in the
diagnosis and service of your vehicle.
PLEASE COMPLETE THE ORDER FORM SHOWN ON
THE FOLLOWING PAGE AND MAIL TO:
Helm, Incorporated P.O. Box 07130 Detroit, MI 48:
OWNER’S INFORMATION
Owner publications are written directly for Owners and
intended to provide basic operational information about
vehicle. The owner’s manual will include the Maintenanl
Schedule for all models.
In-Portfolio: Includes a Portfolio, Owner’s Manual and
Warranty Booklet. RETAIL SELL PRICE: $15.00
Without Portfolio: Owner’s Manual only.
RETAIL SELL PRICE:
$1 0.00
CURRENT & PAST MODEL ORDER FORMS
Service Publications are available for current and past
model
GM vehicles. To request an order form, please
specify year and model name
of the vehicle.
OR ORDER TOLL FREE: 1-800-782-4356
Monday-Friday 8:OO AM - 6:OO PM Eastern Tme
For Credit Card Orders Only
(VISA-MasterCard-Discovr
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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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