
DIESEL ENGINES - MAINTENANCE SCHEDULE yf
20 Air Intake System InspectionAB t t
21 Thermostatically Controlled Engine
Cooling Fan CheckAW-Every
t t
12 Months or
Inspection*
22 Exhaust Pressure Regulator Valve
23 Tire and Wheel Rotation**
t
24 Drive Axle Service** t t t +
25 Brake Systems Inspection**
A Change filter every 15,000 miles (24 000 km), except when op\
erating
in dusty
conditions. Dusty conditions may require more frequent filter re\
placement. Extreme
dust and dirt operating conditions (off-road), may require the air \
filter to be checked as
often as every 300 miles (483 km) and replaced as necessary.
* An Emission Control Service
** See “Explanation of Scheduled Maintenance Services” in this section.
A A Noise Emission Control Service
1 Applicable only to vehicles sold in the United States
t This maintenance schedule applies to all diesel engines available.
T0408/T0908
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Explanation Of Scheduled Mainienance Services
Below are explanations of the services listed in the maintenance charts.
The proper fluids and lubricants to use are listed in this section. 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.
1. ENGINE OIL AND OIL FILTER CHANGE“‘ - ALWAYS USE
SJ3 ENERGY CONSERVING I1 (GASOLINE ENGINE) OR CF-4/SH
(DIESEL ENGINE) QUALITY OILS
OF THE PROPER VISCOSITY.
To determine the preferred viscosity oil for your vehicle’s engine (e.g.
SAE 5W-30 or 10W-30), see “Engine Oil”
in the Index.
2. CHASSIS LUBRICATION - Lubricate the front suspension, king
pin bushings, steering linkage, transmission, and transfer case shift
linkage, parking brake cable guides, rear driveline center splines and
front axle propshaft splines, brake pedal springs, and clutch pedal
springs at the intervals specified.
If you have a 3500
HD, lubricate the king pins and king pin bushings,
every
1,500 miles (2500 km) for Maintenance Schedule I, or every
3,000 (5000 km) for Maintenance Schedule 11.
Ball joints and king pin bushings should not be lubricated unless their
temperature
is 10” F (-12”C), or higher. When the weather is cold, let
them warm up before lubrication or
they could be damaged.
Also, be sure
to check all the vehicle fluid levels at this time.
3.
CLUTCH FORK BALL STUD LUBRICATION (5-SPEED
MANUAL TRANSMISSION WITH DEEP LOW
) - Lubricate the
clutch fork ball stud through the fitting
on the clutch housing.
Lubricant must be added “sparingly” to
the fitting, as only .0066 lb.
(.003 kg) is required to lubricate the ball stud surface. Do not add
lubricant more often than the intervals
in the Maintenance Charts. Too
much lubricant will damage the clutch assembly.
4. COOLING SYSTEM SERVICE”’? - Drain, flush and refill system
with new coolant. See “Engine Coolant” in the Index for
the proper
coolant and mixture to use
in your vehicle.
Also inspect the hoses and replace them
if they are cracked, swollen, or
deteriorated. Tighten all hose clamps (except constant tension clamps).
Remove debris and clean the outside of the radiator and air
conditioning condenser. Wash the radiator neck.
To ensure proper
operation, pressure test.
the radiator and cap.
* An Emission Control Service
?A fluid
loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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5. AIR CLEANER FILTER REPLACEMENT* - Replace at every
30,000 miles (50 000 km) or more often under dusty conditions. Ask
your dealer for the proper replacement intervals for your driving
conditions.
6. FRONT WHEEL BEARING REPACK (2-WHEEL DRIVE
ONLY)
- Clean and repack the front wheel bearings at each brake
relining, or at
the specified interval, whichever comes first.
7. TRANSMISSION SERVICE’/-
Automatic Transmission
- Change the transmission fluid and filter
every
15,000 miles (25 000 km) for vehicles under 8,600 GVWR or
every 12,000 miles
(20 000 km) for vehicles over 8,600 GVWR if the
vehicle is mainly driven under one or more
of these conditions:
In heavy city traffic.
0 Where the outside temperature regularly reaches 90°F (32°C) or
0 In hilly or mountainous terrain.
higher.
Frequent
trailer pulling.
Uses such as taxi, police, delivery or other commercial service.
If the vehicle
is not used mainly under any of these conditions, change
the fluid and filter every
30,000 miles (50 000 km) for vehicles under
8,600
GVWR or every 24,000 miles (40 000 km) for vehicles over
8,600 GVWR see “Automatic Transmission Fluid”
in the Index for
more information.
Manual Transmission - Transmission fluid does not require periodic
changing.
8. CDRV SYSTEM INSPECTION* - Check the Crankcase
Depression Regulator Valve System for any worn, plugged or collapsed
hoses. Have the system checked as described in the Service Manual.
9. FUEL FILTER REPLACEMENT*$ - Replace the fuel filter at the
specified interval or sooner if clogged.
?A fluid loss
in these systems may indicate a problem. Have them
inspected and repaired at once.
:i: An Emission Control Service
$The California Air Resources Board bas 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 useful life.
General Motors, however, urges that all recommended maintenance
services be performed at the indicated intervals and the maintenance be
recorded.
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24. DRIVE AXLE SERVICE? - Check readfront axle fluid level and
add
as needed. Check constant velocity joints and axle seals for
leaking.
0
0
0
0
Locking differential - Drain fluid at first oil change and refill.
Check fluid level and add
as needed at subsequent oil changes. In
dusty areas, or trailer towing applications drain fluid at every
15,000 miles (24 135 kilometers) and refill.
Standard differential - Check fluid level and add as needed at
every
oil change. In dusty areas, or trailer towing applications,
drain fluid every
15,000 miles (24 I35 kilometers) and refill.
More frequent lubrication may be required on heavy-duty or
off-road use.
3500 HD Models - 3500 HD Models with applications requiring
extreme overload/trdiler tow conditions
and high speed conditions
(above 45 mph (72
kdh)) for extended periods of time must
change drive axle fluid every
3,000 miles (4828 kilometers) or 3
months, whichever comes first, OR must use 75W-140 synthetic
fluid meeting
GM specifications. See “Recommended Fluids and
Lubricants” at the end of this section for the proper fluid to use.
25.
BRAKE SYSTEM INSPECTION-f - When the engine oil is
changed, inspect the lines and hoses for proper hookup, binding, leaks,
cracks, chafing, etc. Check the parking brake adjust, and the fluid level
in the master cylinder. A low fluid level can indicate worn disc brake
pads which may need
to be serviced.
When the wheels are removed for rotation, inspect disc brake pads for
wear and rotors for surfxe condition. Also inspect drum brake linings
for wear and cracks. Inspect other brake parts, including drums, wheel
cylinders, parking brake, etc., at the same time. Remove any
rust or dirt
from the wheel and mounting surfaces before mounting the wheel.
Inspect brakes more often if driving habits or conditions result in
frequent braking.
?A fluid loss in these systems may indicate a problem. Have them
inspected and repaired at once.
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Owner Checks and Services
Listed below are owner checks and services which should be made at the
time period specified to help ensure proper safety, emission performance,
and dependability
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 this Section.
At Least Once a Month
Tire inflation pressure check - Check the tires for proper inflation. If
they are low, inflate them to the level specified on the Certification/Tire
label. See “Loading Your Vehicle” or “Inflation-Tire Pressure”
in the Index.
At Least Once a Year
Key lock cylinder lubrication - Lubricate key lock cylinders with engine
oil. See
the “Recommended Fluid and Lubricants” chart in this section.
Transmission neutral or clutch start switch operation -
1. Before you start, be sure you have enough room around the vehicle.
2. Firmly apply both the manual parking brake and the regular brake. See
“Brakes” and “Parking Brake”
in the Index. Do not use the accelerator
pedal.
3. Be ready to turn off the engine immediately if it starts.
4. On automatic transmission vehicles, try to start the engine in each gear.
The starter should work only
in “P’ (Park) or “N” (Neutral).
On manual transmission vehicles, put the shift lever
in “N” (Neutral), push
the clutch down halfway, and try to start the engine. The starter should work
only when the clutch
is pushed down all the way to the floor.
Steering column lock operation - While parked, try to turn the key to
LOCK in each gear shift position.
With an automatic transmission, the key should
turn to LOCK only when
the gear shift
is in “P” (Park).
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On vehicles with a key release lever, try to turn the key to LOCK without
pressing the lever. The key should turn to
LOCK only with the key lever
depressed.
On
all vehicles, the key should come out only in LOCK.
Parking brake and transmission
“P” (PARK) mechanism operation -
I
Park on a fairly steep hill, with the vehicle facing downhill. Keeping your
foot on the regular brake, set the manual parking brake.
To check the parking brake: With the engine running and the
transmission
in “N” (Neutral), 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 “P’ (Park) mechanism’s holding ability: Apply the regular
brake and shift to
“P’ (Park). Release the manual parking brake, then
slowly release the regular brake.
Lap and Shoulder Belts Condition and Operation - Inspect belt system,
including webbing, buckles, latch plates, retractors, guide loops and
anchors. Have
a belt assembly replaced if the webbing has been cut or
otherwise damaged.
Body Lubrication Service - Lubricate all body door hinges with engine
oil. Also lubricate the tailgate, tailgate handle pivot points, and tailgate
mounted spare tire carrier
(if equipped}. Lubricate the body hood, fuel door
and rear compartment hinges, latches and locks including interior glove box
and console doors, and any folding seat hardware. Lubricate the hood safety
lever pivot and prop rod pivot. More frequent lubrication may be required
when exposed to a corrosive environment.
Periodic Maintenance Inspections - Listed below are inspections and
services which should be performed at least twice
a year (for instance each
spring or fall). You should
let your GM dealer’s service department or other
qualified service center do these
jobs. Make sure any necessary repairs are
completed at once.
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Recommended Fluids & Lubricants
NOTE: Fluids and lubricants identified below by name, part number or
specification may be obtained from your GM Dealer.
USAGE
Engine Oil - Gasoline
Engines
Engine
Oil - Diesel Engines
Engine Coolant
Hydraulic Clutch System
Hydraulic Brake Systems
Parking Brake Cables
Power Steering System
Automatic Transmission
FLUIDLUBRICANT
API service SH or SG Energy
Conserving I1 oils
of the recommended
viscosity. The
“SH” designation may be
shown alone or
in combination with
others, such
as “SH/CD,” “SH, SG,
CD,”“SG/CD,” etc. To determine the
preferred viscosity for your vehicle’s
engine, see “Engine Oil” in the Index.
API service CF4SH. The
“CF4SH”
designation may be shown alone or in
combination
with others, such as
“CF-4/SG,” “CE/SH” or “CE/SG,” etc.
The designation may
also be listed in
reverse order, such
as “SH/CF-4.” To
determine the preferred viscosity for
your vehicle’s engine, see “Engine Oil”
in the Index.
Mixture
of water and a good quality
ethylene glycol base antifreeze
conforming
to “GM Specification
6038-M” (GM Part No. 1052753)’ or
approved recycled coolant conforming to
“GM Specification
603%”’ with a
complete coolant flush and refill.
Hydraulic Clutch Fluid (GM Part No.
I2345347 or equivalent).
Delco Supreme
11 @ brake fluid (GM
Part No.
1052535 or equivalent DOT-3
brake fluid).
Chassis Lubricant (GM Part No.
I2346003 or equivalent) or lubricant
meeting requirements of NLGI Grade
2,
Category LB or GC-LB.
GM Power Steering Fluid (GM Part
No. 1050017 or equivalent) conforming
to
“GM Specification 99850 10.”
DEXRON~ 111 or DEXRON~ IIE
Automatic Transmission Fluid.
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Index
A
Aircleaner ..................................................... 6-29
Air Conditioning
............................................ 3.5. 6.S0
Aircontrols
.................................................. 3-7
Low Refrigerant Change Detection
................................ 3-8
Refrigerant Capacity
...................................... 3.97, 6.94
SystemControls
............................................... 3-6
Antenna, FixedMast
............................................. 3-18
Anti-Lock Brakes (See “Brakes”)
Appearancecare
................................................ 6-80
Materials Chart ............................................... 6-87
Arbitration Program
............................................... 8-3
Audiosystems
................................................... 3-9
AMRadio ................................................... 3-10
AM-FM Stereo Audio System with Cassette Deck ................... 3-12
AM-FM Stereo Audio System with Cassette Deck and Equalizer ........ 3-16
Cassette Deck
................................................ 3-14
Cassette Tape Player Care
....................................... 3-30
Automatic Transmission
.......................................... 2-21
Fluid
....................................................... 6-30
Axle Front
....................................................... 6-37
Front Locking Feature
.......................................... 2-36
Rear
........................................................ 6-39
RearLocking
.................................................. 6-39
Battery
........................................................ 6-52
Belts (See “Safety Belts”)
Better Business Bureau Mediation
.................................... 8-3
Blizzard ....................................................... 4-35
Brakes
Anti-Lock
.................................................... 4-6
Fluid
....................................................... 6-47
Leakcheck
.................................................. 6-47
Master Cylinder
.............................................. 6-46
Parking
..................................................... 2-28
PedalTravel ................................................. 6-48
Replacing Parts
............................................... 6-49
System Warning Light
......................................... 2-70
Trailer
...................................................... 441
In Emergencies ................................................ 4-7
Break-In, New Vehicle
........................................... 2- IO
Bulb Replacement ............................................... 6-97
Replacement Chart
............................................ 6-97
Braking
......................................................... 4-5
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