1998 GMC ENVOY engine

Long Tripmighway Maintenance Schedule 1
- When doing frequent trailer towing.
- Uses such as found in taxi, police or delivery service.
If you do not use your vehicle under any of these conditions, change the jluid
andfilter every
50,000 miles (83 000 krn).
An Emission Control Service. (See footnote?.)
An Emission Control Service.
rotation pattern and additional information. (See footnote
+.)
0 Replace fuel filter.
0 Replace air cleaner filter.
0 Rotate tires. See “Tire Inspection and Rotation” in the Index for proper
97,500 Miles (162 500 km)
0 Change engine oil and filter (or every 12 months, whichever occurs first).
0 Lubricate chassis components (or every 12 months, whichever occurs first).
Check readfront axle fluid level and add fluid as needed. Check constant
0 Rotate tires. See “Tire Inspection and Rotation” in the Index for proper
An
Emission Control Service.
(See footnote
#.)
velocity joints and axle seals for leaking. (See footnote **.)
rotation pattern and additional information. (See footnote +.)
DATE
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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 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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Starter Switch Check Brake-Transmission Shift Interlock (BTSI) Check
When you are doing this check, the vehicle could
move suddenly.
If it does, you or others could be
injured. Follow the steps below.
A CAUTION:
I
When you are doing this check, the vehicle could
move suddenly. If it does, you
or others could be
injured. Follow the steps below.
1. Before you start, be sure you have enough room
around
the vehicle.
2. Firmly apply both the parking brake (see “Parking
Brake”
in the Index if necessary) and the
regular brake.
NOTE:
Do not use the accelerator pedal, and be
ready
to turn off the engine immediately if it starts.
3. Try to start the engine in each gear. The starter
should work only in PARK (P) or NEUTRAL (N).
If the starter works in any other position, your
vehicle needs service.
1. Before you start, be sure you have enough room
around the vehicle.
It should be parked on a
level surface.
2. Firmly apply the parking brake (see “Parking Brake”
in the Index if necessary).
NOTE: Be ready to apply the regular brake
immediately if the vehicle begins to move.
3. With the engine off, turn the key to the RUN
position, but don’t start the engine. Without applying
the regular brake, try
to move the shift lever out of
PARK
(P) with normal effort. If the shift lever
moves out of PARK
(P), your vehicle’s BTSI
needs service.
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Ignition Transmission Lock Check
While parked, and with the parking brake set, try to turn
the ignition key to LOCK
in each shift lever position.
The key should turn to LOCK only when the shift
lever is in PARK (P).
The key should come out only in LOCK.
Parking Brake and Automatic Transmission
PARK
(P) Mechanism Check
b-
When you are doing this check, your vehicle
could begin to move.
You or others could be
injured and property could be damaged. Make
sure there is room in front
of your vehicle in case
it begins to roll. Be ready to apply the regular
brake
at once should the vehicle begin to move.
Park on a fairly steep hill, with the vehicle facing
downhill. Keeping your foot
on the regular brake, set the
parking brake.
0 To check the parking brake’s holding ability:
With the engine running and transmission in
NEUTRAL
(N), slowly remove foot pressure from
the regular brake pedal.
Do this until the vehicle is
held by the parking brake only.
0 To check the PARK (P) mechanism’s holding ability:
With the engine running, shift to PARK
(P). Then
release all brakes.
Underbody Flushing Service
At least every spring, use plain water to flush any
corrosive materials from the underbody. Take care
to
clean thoroughly any areas where mud and other debris
can collect.
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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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Part D: Recommended Fluids
and Lubricants
NOTE: Fluids and lubricants identified below by name,
part number or specification may be obtained from
your dealer.
USAGE
Engine Oil
Engine Coolant
Hydraulic Brake
System
FLUIDLUBRICANT
Engine Oil with the American
Petroleum Institute Certified For
Gasoline Engines “Starburst” symbol of the proper viscosity. To
determine the preferred viscosity
for your vehicle’s engine, see
“Engine Oil” in the Index.
50/50 mixture of clean water
(preferably distilled) and use
only
GM Goodwrench@ DEX-COOL@
or Havoline@ DEX-COOL@
Coolant. See “Engine Coolant’’
in
the Index.
Delco Supreme
1 1 @ Brake Fluid
(GM Part No. 12377967 or
equivalent DOT-3 Brake Fluid).
USAGE
Parking Brake
Cable Guides
Power Steering System
Automatic
Transmission
Key Lock
Cylinders
Chassis
Lubrication
Differential,
Front and Rear
Axle
FLUIDLUBRICANT
Chassis Lubricant (GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements of
NLGI
## 2, Category LB or
GC-LB.
GM Power Steering Fluid (GM
Part
No. 1052884 - 1 pint,
10500 17 - 1 quart, or equivalent).
DEXRON@-I11 Automatic
Transmission Fluid.
Multi-Pu
ose Lubricant,
Superlube
% (GM Part
No. 1234624 1 or equivalent).
Chassis Lubricant
(GM Part
No. 12377985 or equivalent) or
lubricant meeting requirements
of
NLGI # 2, Category LB or
GC-LB.
Axle Lubricant (GM Part
No. 1052271) or SAE 8OW-90
GL-5 Gear Lubricant.
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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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