engine JEEP WRANGLER 2008 JK / 3.G Owners Manual

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.WARNING!
Worn brake hoses can burst and cause brake failure.
You could have an accident. If you see any signs of
cracking, scuffing, or worn spots, have the brake
hoses replaced immediately.
Brake Master Cylinder — Brake Fluid Level Check
Refer to Fluids, Lubricants, and Genuine Parts in this
section for the correct fluid type.
WARNING!
Use of a brake fluid that may have a lower initial
boiling point, or is unidentified as to specification,
may result in sudden brake failure during hard
prolonged braking. You could have an accident.
400 MAINTAINING YOUR VEHICLE

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

CAUTION!
Be aware that if the fluid temperature is below 50° F
(10° C), it may not register on the dipstick. Do not add
fluid until the temperature is elevated enough to
produce an accurate reading.
7. Check for leaks. Release the parking brake.
NOTE: To prevent dirt and water from entering the
transmission after checking or replenishing fluid, make
certain that the dipstick cap is properly reseated. It is
normal for the dipstick cap to spring back slightly from
its fully seated positions, as long as its seal remains
engaged in the dipstick tube.
Special Additives
Automatic Transmission Fluid (ATF) is an engineered
product and its performance may be impaired by supple-
mental additives. Therefore, do not add any fluid addi-
tives to the transmission. The only exception to this
policy is the use of special dyes to aid in detecting fluid
leaks. In addition, avoid using transmission sealers as
they may adversely affect seals.
Hydraulic Clutch Fluid — Manual Transmission
The clutch hydraulic system is a sealed maintenance free
system. In the event of leakage or other malfunction, the
system must be replaced.
Manual Transmission
Selection of Lubricant
Use only manufacturer’s recommended manual trans-
mission fluid. Refer to Fluids, Lubricants, and Genuine
Parts in this section for the correct fluid type.
MAINTAINING YOUR VEHICLE 403
7

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.CAUTION!
Under frequent heavy-duty driving conditions,
change all lubricants, and lubricate body compo-
nents more often than in normal service to prevent
excessive wear.
Appearance Care And Protection From Corrosion
Protection Of Body And Paint From Corrosion
Vehicle body care requirements vary according to geo-
graphic locations and usage. Chemicals that make roads
passable in snow and ice, and those that are sprayed on
trees and road surfaces during other seasons, are highly
corrosive to the metal in your vehicle. Outside parking,
which exposes your vehicle to airborne contaminants,
road surfaces on which the vehicle is operated, extreme
406 MAINTAINING YOUR VEHICLE

zipper halves with fresh water and allow to dry. Aggres-
sively work the MOPARSoft Top Zipper Cleaner and
Lubricant into the zipper teeth. If a stuck zipper slide is
experienced, work the MOPAR Soft Top Zipper Cleaner
and Lubricant into the zipper slide. Several applications
may be required before the zipper comes free.
6. Never paste stickers, gummed labels or any tape to the
windows. Adhesives are hard to remove and may dam-
age the windows.
FUSES (TOTALLY INTEGRATED POWER
MODULE)
The Totally Integrated Power Module (TIPM) is located
in the engine compartment near the battery. This center
contains cartridge fuses, mini fuses and relays. A label
that identifies each component is printed on the inside of
the cover.
Cavity Cartridge FuseMini
Fuse Description
J1 — —
J2 30 Amp Pink Transfer Case Module
J3 — —
Integrated Power Module (TIPM)
MAINTAINING YOUR VEHICLE 413
7

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)
Cavity Cartridge FuseMini
Fuse Description
M35 10 Amp
Red Heated Mirrors
M36 20 Amp
Yellow Power Outlet
M37 10 Amp
Red Anti-Lock Brake System
(ABS), Electronic Stabil-
ity Program (ESP), Stop
Lamp Switch (STP LP
SW), Fuel Pump Rly Hi
Control
M38 25 Amp
Natural Lock/Unlock Motors
(LOCK/UNLOCK
MTRS)
418 MAINTAINING YOUR VEHICLE

FLUID CAPACITIES
U.S.Metric
Fuel (Approximate) — 2–Door Models 18.5 Gallons70 Liters
Fuel (Approximate) — 4–Door Models 22.5 Gallons85 Liters
Engine Oil with Filter
3.8 Liter Engine (SAE 5W-20, API Certified Engine Oil) 6 Quarts5.7 Liters
Cooling System *
3.8 Liter Engine (MOPAR Antifreeze/Engine Coolant 5 Year/
100,000 Mile Formula) 13 Quarts
12 Liters
* Includes heater and coolant recovery bottle filled to MAX level.
424 MAINTAINING YOUR VEHICLE

FLUIDS, LUBRICANTS AND GENUINE PARTS
Engine
ComponentFluid, Lubricant, or Genuine Part
Engine Coolant MOPARAntifreeze/Coolant 5 Year/100,000 Mile Formula HOAT (Hybrid
Organic Additive Technology)
Engine Oil Use API Certified SAE 5W-20 Engine Oil, meeting the requirements of
DaimlerChrysler Material Standard MS-6395. Refer to your engine oil filler cap
for correct SAE grade.
Spark Plugs (3.8L Engine) RE14PLP5 (Gap 0.050 in [1.27 mm])
Oil Filter (3.8L Engine) MOPAROil Filter (P/N 04105409AC)
Fuel Selection 87 Octane
MAINTAINING YOUR VEHICLE 425
7

EMISSIONS CONTROL SYSTEM MAINTENANCE
The Scheduled Maintenance services listed inbold type
must be done at the times or mileages specified to ensure
the continued proper functioning of the emission control
system. These, and all other maintenance services in-
cluded in this manual, should be done to provide best
vehicle performance and reliability. More frequent main-
tenance may be needed for vehicles in severe operating
conditions, such as dusty areas and very short trip
driving.
Inspection and service should also be done any time a
malfunction is suspected.
NOTE: Maintenance, replacement, or repair of the emis-
sions control devices and systems on your vehicle may be
performed by any automotive repair establishment or
individual using any automotive part that has been
certified pursuant to U.S. EPA or, in the State of Califor-
nia, California Air Resources Board regulations.
MAINTENANCE SCHEDULE
The oil change indicator system will remind you that it is
time to take your vehicle in for scheduled maintenance.
On Non-EVIC equipped vehicles “CHANgE OIL” will
flash in the instrument cluster odometer and a single
chime will sound, indicating that an oil change is neces-
sary.
Based on engine operation conditions the oil change
indicator message will illuminate, this means that service
is required for your vehicle. Have your vehicle serviced
as soon as possible, within the next 500 mi (805 km).
NOTE:
•The oil change indicator message will not monitor the
time since the last oil change. Change your vehicles oil
if it has been 6 months since your last oil change even
if the oil change indicator message is NOT illumi-
nated.
428 MAINTENANCE SCHEDULES
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