Page 249 of 344
MAINTAINING YOUR VEHICLE
CONTENTS
m4.0L Engine...........................251
m4.7L/4.7 HO Engine.....................252
mOnboard Diagnostic System Ð OBD II........253
mEmissions Inspection And Maintenance
Programs............................254
mReplacement Parts......................255
mDealer Service.........................255
mMaintenance Procedures..................256
NEngine Oil..........................256NDrive Belts - Check Condition And Tension . . . 261
NSpark Plugs.........................261
NCatalytic Converter....................261
NCrankcase Emission Control System........263
NFuel Filter..........................263
NAir Cleaner Filter.....................264
NMaintenance-Free Battery................264
NAir Conditioner Maintenance.............265
NPower Steering Fluid Check..............266
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Page 261 of 344

Drive Belts - Check Condition and Tension
At the mileages shown in the appropriate ªMaintenance
Schedule,º check all drive belts for condition and proper
tension. Improper belt tension can cause belt slippage
and failure.
Inspect the drive belt for evidence of cuts, cracks, or
glazing and replace them if there is any sign of damage
which could result in belt failure. If adjustment is re-
quired, adjust the belts according to the specifications
and procedures shown in the Service Manual.
Special tools are required to properly measure tension
and to restore belt tension to factory specifications. Also,
check belt routing to make sure there is no interference
between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New spark plugs should be
installed at the specified mileage. The entire set should be
replaced if there is any malfunction due to a faulty spark
plug. Refer to the ªVehicle Emission Control Informa-
tionº label in the engine compartment for spark plug
information.
Catalytic Converter
The catalytic converter requires the use of unleaded fuel
only. Leaded gasoline will destroy the effectiveness of the
converter as an emission control device.
Under normal operating conditions, the catalytic con-
verter will not require maintenance. However, it is im-
portant to keep the engine properly tuned to assure
proper catalyst operation and prevent possible catalyst
damage.
MAINTAINING YOUR VEHICLE 261
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Page 265 of 344
To determine the battery charge, check the battery test
indicator (if equipped) on top of the battery. Refer to the
illustration.
CAUTION!
It is essential when replacing the cables on the
battery that the positive cable is attached to the
positive post and the negative cable is attached to the
negative post. Battery posts are marked (+) positive
and negative (-) and identified on the battery case.
Also, if a ªfast chargerº is used while battery is in the
vehicle, disconnect both vehicle battery cables be-
fore connecting the charger to battery. Do not use a
ªfast chargerº to provide starting voltage.
Air Conditioner Maintenance
For best possible performance, your air conditioner
should be checked and serviced by an Authorized Dealer
at the start of each warm season. This service should
include cleaning of the condenser fins and a performance
test. Drive belt tension should also be checked at this
time.
MAINTAINING YOUR VEHICLE 265
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Page 285 of 344

WARNING!
Do not use volatile solvents for cleaning purposes.
Many are potentially flammable, and if used in
closed areas they may cause respiratory harm. Do not
use gasoline, turpentine, kerosene, etc. for cleaning.
Use the Mopartrecommended products or the
equivalents.
Carpet
Vacuum your carpet regularly to prevent a soil build-up.
Shampoo soiled carpet with a reliable upholstery cleaner,
using a natural sponge or soft bristle brush. After carpet
dries, vacuum it thoroughly.
Seat Belt Maintenance
Do not bleach, dye or clean the belts with chemical
solvents or abrasive cleaners. This will weaken the fabric.
Sun damage will also weaken the fabric.If the belts need cleaning, use a mild soap solution or
lukewarm water. Do not remove the belts from the
vehicle to wash them.
Replace the belts if they appear frayed or worn or if the
buckles do not work properly.
Maintenance After Off-Pavement Driving
After extended operation in mud, sand or water, or
similar dirty conditions, have your brake drums, brake
linings, and axle joints inspected and cleaned as soon as
possible. This will prevent any abrasive material from
causing excessive wear or unpredictable braking action.
Following off-pavement usage, completely inspect the
underbody of your vehicle. Check tires, body structure,
steering, suspension and exhaust system for damage.
Check threaded fasteners for looseness, particularly on
the chassis, drivetrain components, steering and suspen-
sion. Retighten, if required, to torque values specified in
the Service Manual. Also check for accumulations of
MAINTAINING YOUR VEHICLE 285
7
Page 302 of 344
Miles 33,000 36,000 39,000 42,000 45,000
(Kilometers) (53 000) (58 000) (62 000) (67 000) (72 000)
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air cleaner filter, replace if nec-
essary.X
Drain and refill the front and rear axles. X
Inspect the brake linings. X
Lubricate the upper knuckle ball stud at steering &
suspension ball joints.XX
Clean and lubricate the brake caliper pins. X
Inspect and replace drive belt, if necessary (4.0L
Only).X
302 SCHEDULE ªBº
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Page 303 of 344
Miles 48,000 51,000 54,000 57,000 60,000
(Kilometers) (77 000) (82 000) (86 000) (91 000) (96 000)
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air cleaner filter, replace if necessary.X
Inspect the PCV Valve, replace if necessary.LX
Replace the spark plugs.X
Lubricate the upper knuckle ball stud at steering & sus-
pension ball joints.XXX
Clean and lubricate brake caliper pins. X X
Inspect the brake linings. X X
Drain and refill the front and rear axles. X X
Drain and refill the automatic transmission fluid, and
change filter (4.0L Only).X
Drain and refill the automatic transmission fluid, and
replace main sump filter (4.7L Only).X
Inspect the drive belt and replace as needed. Not re-
quired if belt was previously replaced (4.0L Only).X
Drain and refill the transfer case fluid (Selec-Trac and
Quadra-Trac Models).X
SCHEDULE ªBº 303
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Page 304 of 344
Miles 63,000 66,000 69,000 72,000 75,000
(Kilometers) (101 000) (106 000) (110 000) (115 000) (120 000)
Change the engine oil and engine oil filter. X X X X X
Inspect the engine air cleaner filter, replace if nec-
essary.X
Lubricate the upper knuckle ball stud at steering &
suspension ball joints.XX
Inspect the brake linings. X
Clean and lubricate the brake caliper pins. X
Drain and refill the front and rear axle fluid. X
Inspect the drive belt and replace as needed. Not
required if belt was previously replaced (4.0L
Only).X
Inspect the drive belt and replace as needed (4.7L
Only).X
304 SCHEDULE ªBº
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Page 306 of 344
Miles 78,000 81,000 84,000 87,000 90,000
(Kilometers) (125 000) (130 000) (134 000) (139 000) (144 000)
Drain and refill the automatic transmission fluid,
replace main sump filter, and spin-on cooler return
filter (if equipped) (4.7L Only).X
Inspect the drive belt and replace as needed. Not
required if belt was previously replaced.X
306 SCHEDULE ªBº
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