MAINTAINING YOUR VEHICLE
CONTENTS
2.4L Engine 223
4.0L Engine 224
Onboard Diagnostic System — OBD II 225
Emissions Inspection And
Maintenance Programs 226
Replacement Parts 227
Dealer Service 227
Maintenance Procedures 228
Engine Oil 228
Drive Belts — Check Condition And Tension . . 231
Spark Plugs 232
Catalytic Converter 232
Engine Timing Belt — 2.4L Engine 233
Ignition Wiring System — 2.4L Engine 233
Crankcase Emission Control System 234
Fuel Filter 234
Engine Air Cleaner Filter 234
Maintenance-Free Battery 234
Air Conditioner Maintenance 235
Power Steering Fluid Check 236
Driveline And Steering Component
Lubrication 237
Body Lubrication 237
Windshield Wiper Blades 237
222 MAINTAINING YOUR VEHICLE
Windshield Washers 238
Exhaust System 238
Cooling System 239
Hoses And Vacuum/Vapor Harnesses 242
Brake System 243
Automatic Transmission 245
Hydraulic Clutch Fluid —
Manual Transmission 246
Manual Transmission 246
Transfer Case 247
Front/Rear Axle Fluid 248
Appearance Care And Protection
From Corrosion 248
■ Fuse Panel 254
Interior Fuses 254
Underhood Fuses
(Power Distribution Center) 256
Vehicle Storage 256
Replacement Bulbs — If Equipped 257
Fluid Capacities 258
I Recommended Fluids, Lubricants And
Genuine Parts 259
Engine 259
Chassis 260
MAINTAINING YOUR VEHICLE 223
224 MAINTAINING YOUR VEHICLE 4.0L ENGINE
MAINTAINING YOUR VEHICLE 225
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 emissions 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. Although your vehicle will usually be drivable and not need towing, see your dealer for service as soon as possible.
CAUTION!
Prolonged driving with the "Malfunction Indica
tor Light" on could cause further damage to the
emission control system. It could also affect fuel
economy and driveability. The vehicle must be
serviced before any emissions tests can be per
formed.
If the "Malfunction Indicator Light" is flashing
while the engine is running, severe catalytic con
verter damage and power loss will soon occur.
Immediate service is required.
226 MAINTAINING YOUR VEHICLE
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 may not be 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.
Turn the ignition to the ON position, but do not crank
or start the engine.
If you crank or start the engine, you will have to start
this test over.
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.
Approximately 15 seconds later, one of two things will
happen:
a. The MIL will flash for about 10 seconds and then
return to being fully illuminated until you turn off
the ignition key or start the engine. This means that
your vehicle’s OBD system is not ready and you
should not proceed to the I/M station.
b. The MIL will not flash at all and will remain fully
illuminated until you turn off the ignition key or
start the engine. This means that your vehicle’s OBD
system is ready and you can proceed to the I/M
station.
MAINTAINING YOUR VEHICLE 227
If your OBD system is not ready, you should see your authorized 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.
REPLACEMENT PARTS
Use of genuine Mopar® parts for normal/scheduled maintenance and repairs is highly recommended to insure the designed performance. Damage or failures caused by the use of non-Mopar® parts for maintenance and repairs will not be covered by the manufacturer’s warranty.
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.
228 MAINTAINING YOUR VEHICLE
WARNING!
You can be badly injured working on or around a motor vehicle. Do only that service work for which you have the knowledge and the proper equipment. If you have any doubt about your ability to perform a service job, take your vehicle to a competent mechanic.
MAINTENANCE PROCEDURES
The pages that follow contain the required maintenance services determined by the engineers who designed your vehicle.
Besides the maintenance items for which there are fixed maintenance intervals, there are other items that should operate satisfactorily without periodic maintenance. However, if a malfunction of these items does occur, it could adversely affect the engine or vehicle performance. These items should be inspected if a malfunction is observed or suspected.
Engine Oil
Checking Oil Level
To assure proper lubrication of your vehicle’s engine, the engine oil must be maintained at the correct level. Check the oil level at regular intervals, such as every fuel stop.
The best time to check the engine oil level is about 5 minutes after a fully warmed engine is shut off, or before starting the engine after it has sat overnight.
Checking the oil while the vehicle is on level ground will improve the accuracy of the oil level readings. Maintain the oil level between the ADD and SAFE markings on the dipstick. Adding 1 U.S. Quart (0.95L) of oil when the reading is at the ADD mark will result in a SAFE reading on these engines.
ENGINE OIL LEVEL DIPSTICK
MAINTAINING YOUR VEHICLE 229
CAUTION!
Overfilling or underfilling the crankcase will cause aeration or loss of oil pressure. This could damage your engine.
Change Engine Oil
Road conditions as well as your kind of driving affect the interval at which your oil should be changed. Check the following to determine if any apply to you:
Day or night temperatures are below 32°F (0°C)
Stop and go driving
Extensive engine idling
Driving in dusty conditions
Short trip driving of less than 10 miles (16.2 km)
More than 50% of your driving is at sustained high
speeds during hot weather, above 90°F (32°C)
Taxi, Police, or delivery service (commercial service)
Trailer towing
Off-road or desert driving
If equipped for and operating with E-85 (ethanol) fuel
If ANY of these apply to you, then change your engine oil at every interval shown in schedule "B" of the "Maintenance Schedules" section of this manual.
If none of these apply to you, then change your engine oil at every interval shown on schedule "A" of the "Maintenance Schedules" section of this manual
NOTE: Under no circumstances should oil change intervals exceed 6,000 miles (10 000 km) or 6 months whichever comes first.
230 MAINTAINING YOUR VEHICLE
Engine Oil Selection
For best performance and maximum protection for all engines under all types of operating conditions, the manufacturer recommends engine oils that are API Certified and meet the requirements of DaimlerChrysler Material Standard MS-6395.
American Petroleum Institute (API) Engine Oil Identification Symbol
This symbol means that the oil has been certified by the American Petroleum Institute (API). The manufacturer only recommends API Certified engine oils.
Engine Oil Viscosity Chart
The proper SAE viscosity grade of engine oil should be selected based on the following recommendation and be within the operating temperature shown in the engine oil viscosity chart.
2.4L Engines
MAINTAINING YOUR VEHICLE 231
4.0L Engines Materials Added To Engine Oils
The manufacturer strongly recommends against the addition 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 additives.
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.
Engine Oil Filter Selection
All of the manufacturer’s engines have a full-flow type disposable oil filter. Use a filter of this type for replacement. The quality of replacement filters varies considerably. Only high quality filters should be used to assure most efficient service. Mopar® engine oil filters are high quality oil filters and are recommended.
Drive Belts — Check Condition and Tension
At the mileage shown in the appropriate "Maintenance Schedule," check all drive belts for condition and proper tension. Improper belt tension can cause belt slippage and failure.
232 MAINTAINING YOUR VEHICLE
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 required, 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 performance and emission control. New plugs should be installed at the mileage specified in the appropriate maintenance chart. The entire set should be replaced if there is any malfunction due to a faulty spark plug.
Refer to the "Vehicle Emission Control Information" 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 converter will not require maintenance. However, it is important to keep the engine properly tuned to assure proper catalyst operation and prevent possible catalyst damage.
CAUTION!
Damage to the catalytic converter can result if your vehicle is not kept in proper operating condition. In the event of engine malfunction, particularly involving engine misfire or other apparent loss of performance, have your vehicle serviced promptly. Continued operation of your vehicle with a severe malfunction could cause the converter to overheat, resulting in possible damage to the converter and vehicle.
MAINTAINING YOUR VEHICLE 233
WARNING!
A hot exhaust system can start a fire if you park over materials that can burn. Such materials might be grass or leaves coming into contact with your exhaust system. Do not park or operate your vehicle in areas where your exhaust system can contact anything that can burn.
In unusual situations involving grossly malfunctioning engine operation, a scorching odor may suggest severe and abnormal catalyst overheating. If this occurs, stop the vehicle, turn off the engine and allow it to cool. Service, including a tune up to manufacturer’s specifications, should be obtained immediately.
To minimize the possibility of catalytic converter damage:
• Do not shut off the engine or interrupt the ignition when the transmission is in gear and the vehicle is in motion.
Do not try to start the engine by pushing or towing the
vehicle.
Do not idle the engine with any spark plug wires
disconnected or removed, such as when diagnostic
testing.
Do not idle the engine for prolonged periods during
very rough idle or malfunctioning operating condi
tions.
Do not allow vehicle to run out of fuel.
NOTE: Intentional tampering with emissions control systems can result in civil penalties being assessed against you.
Engine Timing Belt — 2.4L Engine
Replace the engine timing belt at the intervals described in the appropriate maintenance schedule.
Ignition Wiring System — 2.4L Engine
Replace the ignition cables at the intervals described in the appropriate maintenance schedule.
234 MAINTAINING YOUR VEHICLE
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 compartment before starting the vehicle with the air cleaner removed. Failure to do so can result in serious personal injury.
Maintenance-Free Battery
Your vehicle is equipped with a maintenance-free battery. You will never have to add water, nor is periodic maintenance required.
WARNING!
Battery posts, terminals, and related accessories contain lead and lead compounds. Always wash hands after handling the battery.
MAINTAINING YOUR VEHICLE 235
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 "fast charger" is used while battery is in the vehicle, disconnect both vehicle battery cables before connecting the charger to battery. Do not use a "fast charger" to provide starting voltage.
To determine the battery charge, check the battery test indicator (if equipped) on top of the battery. Refer to the illustration.
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.
236 MAINTAINING YOUR VEHICLE
WARNING!
Use only refrigerants and compressor lubricants approved by the manufacturer for your air conditioning system. Some unapproved refrigerants are flammable and can explode, injuring you. Other unapproved refrigerants or lubricants can cause the system to fail, requiring costly repairs.
The air conditioning system contains refrigerant under high pressure. To avoid risk of personal injury or damage to the system, adding refrigerant or any repair requiring lines to be disconnected should be done by an experienced repairman.
NOTE: Air Conditioning systems found to be contaminated with À/Ñ System Sealers, Stop Leak Products, Seal Conditioners, Compressor Oil, or Refrigerants not approved by the manufacturer, voids the warranty for the Air Conditioning system.
Power Steering Fluid Check
Checking the power steering fluid level at a defined service interval is not required. The fluid should only be checked if a leak is suspected, abnormal noises are apparent, and/or the system is not functioning as anticipated. Coordinate inspection efforts through a certified DaimlerChrysler Dealership."
Refrigerant Recovery and Recycling
R-134a Air Conditioning Refrigerant is a hydrofluorocar-bon (HFC) that is endorsed by the Environmental Protection Agency and is an ozone-saving product. However, the manufacturer recommends that air conditioning service be performed by dealers or other service facilities using recovery and recycling equipment.
WARNING!
Fluid level should be checked on a level surface with the engine off to prevent injury from moving parts, and to insure accurate fluid level reading. Do not overfill. Use only the manufacturer’s recommended fluid.
MAINTAINING YOUR VEHICLE 237
If necessary, add fluid to restore to the proper indicated level. With a clean cloth, wipe any spilled fluid from all surfaces. Refer to Recommended Fluids, Lubricants, and Genuine Parts for correct fluid type.
Driveline And Steering Component Lubrication
U-joints (cardan joints) are sealed and do not require lubrication. Prop shafts, yokes, ball joints and other driveline and steering components may be provided with grease fittings for lubrication. Lubrication of these components at the intervals specified in the appropriate"Maintenance Schedule" in Section 8 is very important, particularly if your vehicle is subjected to off-road or other heavy-duty use. See your authorized dealer for complete service information.
Body Lubrication
Locks and all body pivot points, including such items as seat tracks, doors, tailgate and hood hinges, should be lubricated periodically to assure quiet, easy operation and to protect against rust and wear. Prior to the application of any lubricant, the parts concerned should be wiped clean to remove dust and grit; after lubricating excess oil and grease should be removed. Particular
attention should also be given to hood latching components to insure proper function. When performing other underhood services, the hood latch, release mechanism and safety catch should be cleaned and lubricated.
The external lock cylinders should be lubricated twice a year, preferably in the fall and spring. Apply a small amount of a high quality lubricant such as Mopar® Lock Cylinder Lubricant directly into the lock cylinder.
Windshield Wiper Blades
Clean the rubber edges of the wiper blades and the windshield periodically with a sponge or soft cloth and a mild non-abrasive cleaner. This will remove accumulations of salt or road film.
Operation of the wipers on dry glass for long periods may cause deterioration of the wiper blades. Always use washer fluid when using the wipers to remove salt or dirt from a dry windshield. Avoid using the wiper blades to remove frost or ice from the windshield. Keep the blade rubber out of contact with petroleum products such as engine oil, gasoline, etc.
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