Page 335 of 436
MAINTAINING YOUR VEHICLE
CONTENTS
Engine Compartment – 3.7L...............338
Engine Compartment – 4.0L...............339
Onboard Diagnostic System — OBD II........340
▫Loose Fuel Filler Cap Message............340
Emissions Inspection And Maintenance
Programs............................341
Replacement Parts......................342
Dealer Service.........................343
Maintenance Procedures..................343▫Engine Oil..........................343
▫Drive Belts — Check Condition
And Tension.........................347
▫Spark Plugs.........................347
▫Catalytic Converter....................348
▫Crankcase Emission Control System........350
▫Fuel Filter..........................350
▫Engine Air Cleaner Filter................350
▫Maintenance-Free Battery................351
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Engine Oil Viscosity (3.7L Engine)
SAE 5W-20 engine oil is recommended for all operating
temperatures. This engine oil improves low tempera-
ture starting and vehicle fuel economy. Your engine oil
filler cap shows the recommended engine oil viscosity
for your vehicle.
Lubricants which do not have both, the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber should not be used.
Engine Oil Viscosity (4.0L Engine)
SAE 10W-30 engine oil is recommended for all operat-
ing temperatures. This engine oil improves low tem-
perature starting and vehicle fuel economy. Your engine
oil filler cap shows the recommended engine oil vis-
cosity for your vehicle.
Lubricants which do not have both, the engine oil certi-
fication mark and the correct SAE viscosity grade num-
ber should not be used.
Materials Added To Engine Oils
The manufacturerstrongly recommendsagainst the ad-
dition of any additives (other than leak detection dyes) to
engine oil. Engine oil is an engineered product and it’s
performance may be impaired by supplemental addi-
tives.
Disposing of Used Engine Oil
Care should be taken in disposing of used engine oil from
your vehicle. Used oil, indiscriminately discarded, can
present a problem to the environment. Contact your
authorized dealer, service station, or governmental
agency for advice on how and where used oil can be
safely discarded in your area.
Engine Oil Filter
The engine oil filter should be replaced at every engine
oil change.
NOTE:For best access to the oil filter, a drive on hoist
should be used instead of a chassis hoist (3.7L Only).
346 MAINTAINING YOUR VEHICLE
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Crankcase Emission Control System
Proper operation of this system depends on freedom
from sticking or plugging due to deposits. As vehicle
mileage builds up, the PCV valve and passages may
accumulate deposits. If a valve is not working properly,
replace it with a new valve. DO NOT ATTEMPT TO
CLEAN THE OLD PCV VALVE!
Check ventilation hose for indication of damage or
plugging deposits. Replace if necessary.
Fuel Filter
A plugged fuel filter can cause hard starting or limit the
speed at which a vehicle can be driven. Should an
excessive amount of dirt accumulate in the fuel tank,
frequent replacement of the fuel filter which is mounted
in the fuel tank may be necessary.
Engine Air Cleaner Filter
Under normal driving conditions, replace the air filter at
the intervals shown on “Maintenance Schedule A.” If,
however, you drive the vehicle frequently under dusty or
severe conditions, the filter element should be inspected
periodically and replaced if necessary at the intervals
shown on “Maintenance Schedule B.”
WARNING!
The air cleaner can provide protection in the case of
engine backfire. Do not remove the air cleaner
unless it is necessary for repair or maintenance.
Make sure that no one is near the engine compart-
ment before starting the vehicle with the air cleaner
removed. Failure to do so can result in serious
personal injury.
350 MAINTAINING YOUR VEHICLE
Page 390 of 436
Miles 3,000 6,000 9,000 12,000 15,000
(Kilometers) (5 000) (10 000) (15 000) (20 000) (25 000)
Change the engine oil and engine oil filter, if not
replaced at 3 months.X X XXX
Rotate the tires. X X
Inspect the engine air filter element, replace if
necessary.X
Inspect the brake linings. X
Drain and refill the front and rear axle fluid. X
Inspect the transfer case fluid, add if necessary. X
390 SCHEDULE “B”
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Miles 18,000 21,000 24,000 27,000 30,000
(Kilometers) (30 000) (35 000) (40 000) (45 000) (50 000)
Change the engine oil and engine oil filter, if not
replaced at 3 months.X X XXX
Rotate the tires. X X X
Inspect the engine air filter element, replace if
necessary.X
Inspect the PCV Valve, and replace if necessary. X
Replace the spark plugs (3.7L Only).X
Inspect the brake linings. X
Drain and refill the front and rear axle fluid. X
Inspect the manual transmission fluid, add as nec-
essary (3.7L Only).X
Inspect the transfer case fluid, add if necessary. X
SCHEDULE “B” 391
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Miles 33,000 36,000 39,000 42,000 45,000
(Kilometers) (55 000) (60 000) (65 000) (70 000) (75 000)
Change the engine oil and engine oil filter, if not
replaced at 3 months.X X XXX
Rotate the tires. X X
Inspect the engine air filter element, replace if
necessary.X
Inspect the brake linings. X
Drain and refill the front and rear axle fluid. X
Inspect the transfer case fluid, add if necessary. X
Inspect the drive belt, and replace as needed. X
392 SCHEDULE “B”
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Miles 48,000 51,000 54,000 57,000 60,000
(Kilometers) (80 000) (85 000) (90 000) (95 000) (100 000)
Change the engine oil and engine oil filter, if not
replaced at 3 months.X X XXX
Rotate the tires. X X X
Inspect the engine air filter element, replace if
necessary.X
Inspect the PCV Valve, and replace if necessary. X
Replace the spark plugs (3.7L Only).X
Inspect the brake linings. X X
Drain and refill the front and rear axle fluid. X
Inspect manual transmission fluid, add as neces-
sary (3.7L Only).X
Drain and refill the automatic transmission fluid.
Replace main sump filter and spin-on cooler return
filter (if equipped).‡X
Inspect the drive belt, and replace as needed. Not
required if belt was previously.X
SCHEDULE “B” 393
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Page 395 of 436
Miles 63,000 66,000 69,000 72,000 75,000
(Kilometers) (105 000) (110 000) (115 000) (120 000) (125 000)
Change the engine oil and engine oil filter, if not
replaced at 3 months.X X XXX
Rotate the tires. X X
Inspect the engine air filter element, replace if
necessary.X
Inspect the brake linings. X
Inspect the transfer case fluid, add if necessary. 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.X
SCHEDULE “B” 395
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