engine JEEP WRANGLER 2008 Owner's Guide

Drive Belts — Check Condition and Tension
Belt tension is controlled by means of an automatic
tensioner. No belt tension adjustments are required.
However, belt and belt tensioner condition should be
inspected at the specified intervals, and replaced if re-
quired. See your authorized dealer for service
At the mileage indicated in the Maintenance Schedule,
the condition of all the belts and tensioner should be
checked. Refer to Section 8 of this manual. Improper belt
tension can cause belt slippage and failure.
Belts should be inspected for evidence of cuts, cracks,
glazing, or frayed cords and replaced if there is indication
of damage, which could result in belt failure. Low
generator belt tension can cause battery failure.
Also, check belt routing to make sure there is no inter-
ference between the belts and other engine components.
Spark Plugs
Spark plugs must fire properly to assure engine perfor-
mance and emission control. New plugs should be in-
stalled at the mileage specified in the Maintenance Sched-
ule. Refer to Section 8 of this manual. The entire set
should be replaced if there is any malfunction due to a
faulty spark plug. Refer to Fluids, Lubricants, and Genu-
ine Parts in this section 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.
386 MAINTAINING YOUR VEHICLE

To minimize the possibility of catalytic converter dam-
age:
•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.
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.
388 MAINTAINING YOUR VEHICLE

Driveline And Steering Component Lubrication
All driveline and steering components are sealed and do
not require lubrication. Driveshafts are not serviceable.
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 appli-
cation 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 compo-
nents to ensure 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 smallamount 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 accumula-
tions 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.
392 MAINTAINING YOUR VEHICLE

Adding Engine Coolant
Your vehicle has been built with an improved antifreeze/
coolant that allows extended maintenance intervals. This
antifreeze/coolant can be used up to 5 Years or 100,000
mi (160 000 km) before replacement. To prevent reducing
this extended maintenance period, it is important that
you use the same antifreeze/coolant throughout the life
of your vehicle. Please review these recommendations for
using Hybrid Organic Additive Technology (HOAT)
antifreeze/coolant. When adding antifreeze/coolant:
•The manufacturer recommends using MOPAR
Antifreeze/Coolant 5 Year/100,000 Mile Formula
HOAT (Hybrid Organic Additive Technology).
•Mix a minimum solution of 50% HOAT engine coolant
and distilled water. Use higher concentrations (not to
exceed 70%) if temperatures below -34°F (-37°C) are
anticipated.
•Use only high purity water such as distilled or deion-
ized water when mixing the water/engine coolant
solution. The use of lower quality water will reduce
the amount of corrosion protection in the engine
cooling system.
Please note that it is the owner’s responsibility to main-
tain the proper level of protection against freezing ac-
cording to the temperatures occurring in the area where
the vehicle is operated.
NOTE: Mixing antifreeze/coolant types will decrease
the life of the antifreeze/coolant and will require more
frequent antifreeze/coolant changes.
Cooling System Pressure Cap
The cap must be fully tightened to prevent loss of
antifreeze/coolant, and to ensure that antifreeze/coolant
will return to the radiator from the coolant reserve tank.
396 MAINTAINING YOUR VEHICLE

When additional antifreeze/coolant is needed to main-
tain the proper level, it should be added to the coolant
bottle. Do not overfill.
Points To Remember
NOTE:When the vehicle is stopped after a few miles of
operation, you may observe vapor coming from the front
of the engine compartment. This is normally a result of
moisture from rain, snow, or high humidity accumulat-
ing on the radiator and being vaporized when the
thermostat opens, allowing hot antifreeze/coolant to
enter the radiator.
If an examination of your engine compartment shows no
evidence of radiator or hose leaks, the vehicle may be
safely driven. The vapor will soon dissipate.
•Do not overfill the coolant bottle.
•Check antifreeze/coolant freeze point in the radiator
and in the coolant recovery bottle. If antifreeze/ coolant needs to be added, contents of coolant recov-
ery bottle must also be protected against freezing.
•If frequent antifreeze/coolant additions are required,
or if the level in the recovery bottle does not drop
when the engine cools, the cooling system should be
pressure-tested for leaks.
•Maintain antifreeze/coolant concentration at 50%
HOAT antifreeze/coolant (minimum) and distilled
water for proper corrosion protection of your engine
which contains aluminum components.
•Make sure that the radiator and coolant recovery
bottle hoses are not kinked or obstructed.
•Keep the front of the radiator clean. If your vehicle is
equipped with air conditioning, keep the front of the
condenser clean, also.
•Do not change the thermostat for summer or winter
operation. If replacement is ever necessary, install
398 MAINTAINING YOUR VEHICLE

Brake and Power Steering System Hoses
When servicing the vehicle for scheduled maintenance,
inspect surface of hoses for evidence of heat and me-
chanical damage. Hard and brittle rubber, cracking, tears,
cuts, abrasion, and excessive swelling suggest deteriora-
tion of the rubber. Particular attention should be made to
examining those hose surfaces nearest to high heat
sources, such as the exhaust manifold.
Inspect all hose clamps and couplings to make sure they
are secure and no leaks are present.
NOTE:Inspection of brake hoses should be done when-
ever the brake system is serviced and every engine oil
change.

To properly check the automatic transmission fluid level,
the following procedure must be used:
1. Operate the engine at idle speed and normal operating
temperature.
2. The vehicle must be on level ground.
3. Fully apply parking brake.
4. Place the gear selector momentarily in each gear
position ending with the lever in PARK.
5. Remove the dipstick, wipe it clean and reinsert it until
seated.
6. Remove the dipstick again and note the fluid level on
both sides. The fluid level should be between the HOT
(upper) reference holes on the dipstick at normal operat-
ing temperature. Verify that a solid coating of oil is seen
on both sides of the dipstick. If the fluid is low, add as
required into the dipstick tube.Do not overfill.Afteradding any quantity of oil through the dipstick tube, wait
a minimum of two minutes for the oil to fully drain into
the transmission before rechecking the fluid level.
NOTE:
If it is necessary to check the transmission below
the operating temperature, the fluid level should be
between the two cold (lower) holes on the dipstick with
the fluid at approximately 70° F (21° C) (room tempera-
ture). If the fluid level is correctly established at room
temperature, it should be between the HOT (upper)
reference holes when the transmission reaches 180° F (21°
C). Remember it is best to check the level at the normal
operating temperature.
402 MAINTAINING YOUR VEHICLE

Following off-road usage, completely inspect the under-
body of your vehicle. Check tires, body structure, steer-
ing, suspension and exhaust system for damage. Check
threaded fasteners for looseness, particularly on the
chassis, drivetrain components, steering and suspension.
Retighten, if required, to torque values specified in the
Service Manual. Also check for accumulations of vegeta-
tion or brush that could become a fire hazard, or conceal
damage to fuel lines, brake hoses, axle pinion seals, and
propeller shafts. Check air conditioning drain tube on the
lower dash wall in the engine compartment for mud or
debris, and clean as required. A plugged tube will
adversely affect air conditioning performance.

Cavity CartridgeFuseMini
Fuse Description
M30 15 Amp
Blue Wiper Motor Frt, J1962
Diagnostic Feed
M31 20 Amp
Yellow Backup Lamps (B/U
LAMPS)
M32 10 Amp
Red Occupant Restraint
Controller (ORC), TT
EUROPE
M33 10 Amp
Red Next Generation Con-
troller (NGC), Global
Powertrain Engine
Controller (GPEC)
M34 10 Amp
Red
Park Assist (PRK ASST),
Heater Ventilation, Air
Conditioning Module
(HVAC MOD), Headlamp
Wash (HDLP WASH),
Compass (COMPAS)

WARNING!
Engine exhaust, some of its constituents, and certain
vehicle components contain, or emit, chemicals
known to the State of California to cause cancer and
birth defects or other reproductive harm. In addition,
certain fluids contained in vehicles and certain prod-
ucts of component wear contain, or emit, chemicals
known to the State of California to cause cancer and
birth defects or other reproductive harm.
WARRANTY INFORMATION (U.S. Vehicles Only)
See the Warranty Information Booklet for the terms and
provisions of DaimlerChrysler’s warranties applicable to
this vehicle.
MOPARPARTS
MOPAR fluids, lubricants, parts, and accessories are
available from your authorized dealer. They will help
you keep your vehicle operating at its best.
REPORTING SAFETY DEFECTS
In The 50 United States And Washington, D.C.
If you believe that your vehicle has a defect that could
cause a crash or cause injury or death, you should
immediately inform the National Highway Traffic Safety
Administration (NHTSA) in addition to notifying the
manufacturer.
If NHTSA receives similar complaints, it may open an
investigation, and if it finds that a safety defect exists in
a group of vehicles, it may order a recall and remedy
campaign. However, NHTSA cannot become involved in
individual problems between you, your authorized
dealer, and the manufacturer.
440 IF YOU NEED CONSUMER ASSISTANCE