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MAINTAINING YOUR VEHICLE
CONTENTS
Engine Compartment— 3.7L/4.7L...........348
Engine Compartment— 5.7L...............349
Onboard Diagnostic System (OBD II).........350
Emissions Inspection And Maintenance
Programs............................351
Dealer Service.........................352
Replacement Parts......................353
Maintenance Procedures..................353
▫Engine Oil..........................353▫Engine Oil Filter......................357
▫Drive Belts — Check Condition And
Tensioner...........................357
▫Spark Plugs.........................358
▫Engine Air Cleaner Filter................358
▫Engine Fuel Filter.....................358
▫Catalytic Converter....................359
▫Emission-Related Components............361
▫Maintenance Free Battery................361
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▫Air Conditioner Maintenance.............362
▫Power Steering — Fluid Check............363
▫Front Suspension Ball Joints..............364
▫Steering Linkage — Inspection............365
▫Half-Shaft Constant Velocity Joints.........365
▫Front Prop Shaft Lubrication — 2500/3500
(4X4) Models........................365
▫Body Lubrication.....................366
▫Windshield Wiper Blades................366
▫Windshield Washers...................366
▫Exhaust System......................367
▫Cooling System.......................368
▫Hoses And Vacuum/Vapor Harnesses.......372▫Brake System........................372
▫Clutch Hydraulic System................374
▫Clutch Linkage.......................374
▫Rear Axle And 4X4 Front Driving Axle
Fluid Level..........................374
▫Transfer Case........................375
▫Manual Transmission..................376
▫Automatic Transmission................377
▫Front Wheel Bearings..................380
▫Selection Of Lubricating Grease...........380
▫Noise Control System Required Maintenance &
Warranty For 3500 2-Wheel Drive And 4-Wheel
Drive Models Over 10,000 Lbs. (4 535 Kg)
Gross Vehicle Weight Rating..............381
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▫Appearance Care And Protection From
Corrosion...........................385
Fuse And Relay Center...................389
Vehicle Storage........................390
Replacement Light Bulbs.................390
Bulb Replacement......................391
▫Headlight (Halogen)/Front Park And Turn
Lights.............................391
▫Tail, Stop, Turn And Backup Lights.........395
▫Center High-Mounted Stoplight With Cargo
Light..............................397▫Cab Top Clearance Lights — If Equipped....398
▫Tailgate ID Lights (Dual Rear Wheels).......400
▫Side Marker Lights (Dual Rear Wheels)......401
▫Fog Lights..........................402
Fluids And Capacities...................403
Recommended Fluids, Lubricants And Genuine
Parts................................405
▫Engine.............................405
▫Chassis............................406
MAINTAINING YOUR VEHICLE 347
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ENGINE COMPARTMENT— 3.7L/4.7L
348 MAINTAINING YOUR VEHICLE
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ENGINE COMPARTMENT— 5.7L
MAINTAINING YOUR VEHICLE 349
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ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Your vehicle is equipped with a sophisticated onboard
diagnostic system called OBD II. This system monitors
the performance of the emissions, engine, and automatic
transmission control systems. When these systems are
operating properly, your vehicle will provide excellent
performance and fuel economy, as well as engine emis-
sions well within current government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light.” It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be driveable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
Prolonged driving with the “Malfunction Indicator
Light” on could cause further damage to the emis-
sion control system. It could also affect fuel economy
and driveability. The vehicle must be serviced before
any emissions tests can be performed.
If the “Malfunction Indicator Light” is flashing,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
350 MAINTAINING YOUR VEHICLE
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EMISSIONS INSPECTION AND MAINTENANCE
PROGRAMS
In some localities, it may be a legal requirement to pass
an inspection of your vehicle’s emissions control system.
Failure to pass could prevent vehicle registration.
For states which have an I/M (Inspection and
Maintenance) requirement, this check verifies the
following: the MIL (Malfunction Indicator Lamp)
is functioning and is not on when the engine is running,
and that the OBD (On Board Diagnostic) system is ready
for testing.
Normally, the OBD system will be ready. The OBD
system maynotbe ready if your vehicle was recently
serviced, if you recently had a dead battery, or a battery
replacement. If the OBD system should be determined
not ready for the I/M test, your vehicle may fail the test.Your vehicle has a simple ignition key actuated test
which you can use prior to going to the test station. To
check if your vehicle’s OBD system is ready, you must do
the following:
1. Insert your ignition key into the ignition switch.
2. Turn the ignition to the ON position, but do not crank
or start the engine.
3. If you crank or start the engine, you will have to start
this test over.
4. As soon as you turn your key to the ON position, you
will see your MIL symbol come on as part of a normal
bulb check.
MAINTAINING YOUR VEHICLE 351
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5. Approximately 15 seconds later, one of two things will
happen:
a. The MIL light will blink for approximately 5 sec-
onds and then remain on until the first engine crank or
the key is turned off. This means that your vehicle’s
OBD system isnot readyand you shouldnotproceed
to the I/M station.
b. The MIL light will remain fully illuminated until the
first engine crank or the key is turned off. This means
that your vehicle’s OBD system isreadyand you can
proceed to the I/M station.
If your OBD system isnot ready,you should see your
dealer or repair facility. If your vehicle was recently
serviced or had a battery failure or replacement, you may
need to do nothing more than drive your vehicle as you
normally would in order for your OBD system to update.
A recheck with the above test routine may then indicate
that the system is now ready.Regardless of whether your vehicle’s OBD system is
ready or not ready, if the MIL symbol is illuminated
during normal vehicle operation, you should have your
vehicle serviced before going to the I/M station. The I/M
station can fail your vehicle because the MIL symbol is on
with the engine running.
DEALER SERVICE
Your dealer has the qualified service personnel, special
tools and equipment to perform all service operations in
an expert manner. Service manuals are available which
include detailed service information for your vehicle.
Refer to these manuals before attempting any procedure
yourself.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
352 MAINTAINING YOUR VEHICLE