oil filter JEEP YJ 1995 Service And Repair Manual

MAINTENANCE SCHEDULES
INTRODUCTION
There are two maintenance schedules that show
proper service intervals for Jeep Cherokee and Jeep
Wrangler vehicles. Use the schedule that best de-
scribes the conditions the vehicle is operated under.
When mileage and time is listed, follow the interval
that occurs first.
ScheduleÐAlists all the scheduled maintenance
to be performed under normal operating conditions.
ScheduleÐBis a schedule for vehicles that are
usually operated under one or more of the following
conditions.
²Frequent short trip driving less than 5 miles (8
km).
²Frequent driving in dusty conditions.
²Trailer towing or heavy load hauling.
²Frequent long periods of engine idling.
²Sustained high speed operation.
²Desert operation.
²Frequent starting and stopping.
²Cold climate operation.
²Off road driving.
²Commercial service.
²Snow plow operation.
²More than half of vehicle operation occurs in
heavy city traffic during hot weather (above 90É F).
AT EACH STOP FOR GASOLINE
²Check engine oil level and add as required.
²Check windshield washer solvent and add as re-
quired.
ONCE A MONTH
²Check tire pressure and look for unusual tire wear
or damage.
²Check fluid levels of coolant reservoir, brake mas-
ter cylinder, power steering and transmission. Add
fluid as required.
²Check all lights and other electrical items for cor-
rect operation.
²Inspect battery and clean and tighten terminals as
required.
²Check rubber seals on each side of the radiator for
proper fit.
AT EACH OIL CHANGE
²Inspect exhaust system.
²Inspect brake hoses.
²Rotate the tires at each oil change interval shown
on ScheduleÐA: (7,500 Miles) or every other interval
shown on ScheduleÐB: (6,000 Miles).
²Check engine coolant level, hoses, and clamps.
²Lubricate 4x4 steering linkage.
²Lubricate propeller shaft universal joints and slip
spline, if equipped.After completion of off-road (4WD) operation, the
underside of the vehicle should be thoroughly in-
spected. Examine threaded fasteners for looseness.
HARSH SURFACE ENVIRONMENTS
After vehicle operation in a harsh surface environ-
ment, the following components should be inspected
and cleaned as soon as possible:
²Brake drums.
²Brake linings.
²Front wheel bearings (2WD vehicles only).
²Axle coupling joints.
This will prevent wear and/or unpredictable brake
action.
EMISSION CONTROL SYSTEM MAINTENANCE
The schedule emission maintenance listed inbold
typeon the following schedules, must be done at the
mileage specified to assure the continued proper
functioning of the emission control system. These,
and all other maintenance services included in this
manual, should be done to provide the best vehicle
performance and reliability. More frequent mainte-
nance may be needed for vehicles in severe operating
conditions such as dusty areas and very short trip
driving.
SCHEDULEÐA
7,500 MILES (12 000 KM) OR AT 6 MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
15,000 MILES (24 000 KM) OR AT 12 MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
22,500 MILES (36 000 KM) OR AT 18 MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Inspect brake linings.
30,000 MILES (48 000 KM) OR AT 24 MONTHS
²Replace air cleaner element.
²Replace spark plugs.
²Adjust belt tension on non-automatic tensioning
drive belts.
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
²Drain and refill automatic transmission.
²Drain and refill transfer case.
0 - 4 LUBRICATION AND MAINTENANCEJ

37,500 MILES (60 000 KM) OR AT 30 MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill manual transmission.
45,000 MILES (72 500 KM) OR AT 36 MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
²Inspect brake linings.
²Flush and replace engine coolant, regardless of
mileage.
52,500 MILES (84 500 KM) OR AT 42 MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Flush and replace engine coolant if not done at 36
months.
60,000 MILES (96 500 KM) OR AT 48 MONTHS
²Replace air cleaner element.
²Replace distributor cap and rotor.
²Replace ignition wires.
²Replace spark plugs.
²Adjust or replace drive belts.
²Change engine oil.
²Replace engine oil filter.
²Replace fuel filter. (See Note #1)
²Lubricate steering linkage.
²Drain and refill automatic transmission.
²Drain and refill transfer case.
67,500 MILES (108 500 KM) OR AT 54
MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Inspect brake linings.
75,000 MILES (120 500 KM) OR AT 60
MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
²Drain and refill manual transmission.
²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
82,500 MILES (133 000 KM) OR AT 66
MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
90,000 MILES (145 000 KM) OR AT 72
MONTHS
²Replace air cleaner element.
²Replace spark plugs.
²Adjust drive belts.
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
²Inspect brake linings.
²Drain and refill automatic transmission.
²Drain and refill transfer case.
97,500 MILES (157 000 KM) OR AT 78
MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
105,000 MILES (169 000 KM) OR AT 84
MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
112,500 MILES (181 000 KM) OR AT 90
MONTHS
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Inspect brake linings.
²Drain and refill manual transmission.
²Flush and replace engine coolant if it has been
30,000 miles (48 000 km) or 24 months since last
change.
120,000 MILES (193 000 KM) OR AT 96
MONTHS
²Replace air cleaner element.
²Replace distributor cap and rotor.
²Lubricate steering linkage.
²Drain and refill automatic transmission.
²Drain and refill transfer case.
²Replace ignition wires.
²Replace spark plugs.
²Adjust or replace drive belts.
²Change engine oil.
²Replace engine oil filter.
²Replace fuel filter. (See note #1)
JLUBRICATION AND MAINTENANCE 0 - 5

SCHEDULEÐB
3,000 MILES (4 800KM)
²Change engine oil.
²Replace engine oil filter.
6,000 MILES (9 600KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
9,000 MILES (14 400KM)
²Change engine oil.
²Replace engine oil filter.
12,000 MILES (19 200KM)
²Change engine oil.
²Replace engine oil filter.
²Drain and refill automatic transmission.
²Change front and rear axle fluid.*
²Lubricate steering linkage (4x4).
²Inspect brake linings.
15,000 MILES (24 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x2).
²Inspect air cleaner element, replace as necessary.
18,000 MILES (29 000KM)
²Change engine oil.
²Replace engine oil filter.
²Drain and refill Manual transmission fluid.
²Lubricate steering linkage (4x4).
21,000 MILES (34 000KM)
²Change engine oil.
²Replace engine oil filter.
24,000 MILES (38 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill automatic transmission.
²Change front and rear axle fluid.*
²Inspect brake linings.
²Inspect front wheel bearings, Clean and repack if
required (4x2).
27,000 MILES (43 000KM)
²Change engine oil.
²Replace engine oil filter.
30,000 MILES (48 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage joints.
²Replace spark plugs.
²Replace air cleaner element.²Adjust drive belts.
²Drain and refill transfer case fluid.
33,000 MILES (53 000KM)
²Change engine oil.
²Replace engine oil filter.
36,000 MILES (58 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill automatic transmission.
²Drain and refill manual transmission fluid.
²Change front and rear axle fluid.*
²Inspect brake linings.
39,000 MILES (62 000KM)
²Change engine oil.
²Replace engine oil filter.
42,000 MILES (67 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
45,000 MILES (72 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x2).
²Inspect air cleaner element, replace as necessary.
48,000 MILES (77 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill automatic transmission.
²Change front and rear axle fluid.*
²Inspect brake linings.
51,000 MILES (82 000KM)
²Change engine oil.
²Replace engine oil filter.
²Flush and replace engine coolant.
54,000 MILES (86 400KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill Manual transmission fluid.
57,000 MILES (91 000KM)
²Change engine oil.
²Replace engine oil filter.
60,000 MILES (96 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage joints.
²Replace spark plugs.
0 - 6 LUBRICATION AND MAINTENANCEJ

²Drain and refill automatic transmission fluid.
²Change front and rear axle fluid.*
²Replace air cleaner element.
²Replace distributor cap and rotor.
²Replace ignition wires.
²Adjust or replace drive belts.
²Replace fuel filter. See note #1.
²Inspect brake linings.
²Drain and refill transfer case.
63,000 MILES (102 000KM)
²Change engine oil.
²Replace engine oil filter.
66,000 MILES (105 600KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
69,000 MILES (110 000KM)
²Change engine oil.
²Replace engine oil filter.
72,000 MILES (115 200KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill Manual transmission fluid.
²Drain and refill automatic transmission.
²Change front and rear axle fluid.*
²Inspect brake linings.
75,000 MILES (120 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x2).
²Inspect air cleaner element, replace as necessary.
78,000 MILES (125 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
81,000 MILES (130 000KM)
²Change engine oil.
²Replace engine oil filter.
²Flush and replace engine coolant.
84,000 MILES (134 400KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill automatic transmission fluid.
²Change front and rear axle fluid.*
²Inspect brake linings.
87,000 MILES (140 000KM)
²Change engine oil.
²Replace engine oil filter.
90,000 MILES (144 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
²Replace spark plugs.
²Drain and refill Manual transmission fluid.
²Replace air cleaner element.
²Adjust drive belts.
²Drain and refill transfer case fluid.
93,000 MILES (149 000KM)
²Change engine oil.
²Replace engine oil filter.
96,000 MILES (154 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill automatic transmission fluid.
²Change front and rear axle fluid.*
²Inspect brake linings.
99,000 MILES (158 400KM)
²Change engine oil.
²Replace engine oil filter.
102,000 MILES (163 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
105,000 MILES (168 000KM)
²Change engine oil.
²Replace engine oil filter.
²Inspect air cleaner element, replace as necessary.
²Lubricate steering linkage (4x2).
108,000 MILES (172 800KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
²Drain and refill Manual transmission fluid.
²Drain and refill automatic transmission fluid.
²Change front and rear axle fluid.*
²Inspect brake linings.
111,000 MILES (177 600KM)
²Change engine oil.
²Replace engine oil filter.
²Flush and replace engine coolant.
114,000 MILES (182 400KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage (4x4).
117,000 MILES (187 200KM)
²Change engine oil.
²Replace engine oil filter.
JLUBRICATION AND MAINTENANCE 0 - 7

120,000 MILES (192 000KM)
²Change engine oil.
²Replace engine oil filter.
²Lubricate steering linkage.
²Replace spark plugs.
²Drain and refill automatic transmission fluid.
²Change front and rear axle fluid.*
²Inspect brake linings.
²Replace air cleaner element.
²Replace distributor cap and rotor.
²Replace ignition wires.
²Adjust or replace drive belts.
²Replace fuel filter. See note #1.²Drain and refill transfer case fluid.
NOTE 1:Not required for California vehicles, rec-
ommended for proper vehicle performance.
* Off-highway operation, trailer towing, taxi, limou-
sine, bus, snow plowing, or other types of commercial
service or prolonged operation with heavy loading,
especially in hot weather, require front and rear axle
service indicated witha*inScheduleÐB. Perform
these services if you usually operate your vehicle un-
der these conditions.
Inspection and service should also be performed
anytime a malfunction is observed or suspected.
0 - 8 LUBRICATION AND MAINTENANCEJ

ENGINE MAINTENANCE
INDEX
page page
Accessory Drive Belt....................... 21
Air Cleaner Element....................... 18
Air-Conditioner Compressor.................. 21
Battery................................. 20
Crankcase Ventilation System................ 19
Emission Control System................... 20
Engine Break-In.......................... 15
Engine Cooling System..................... 18
Engine Oil.............................. 15Engine Oil Change and Filter Replacement...... 16
Engine Oil Filter.......................... 17
Engine Supports.......................... 21
Exhaust System.......................... 21
Fuel Filter............................... 19
Fuel Usage StatementÐGas Engines.......... 19
Ignition Cables, Distributor Cap and Rotor....... 20
Rubber and Plastic Component Inspection....... 20
Spark Plugs............................. 20
ENGINE BREAK-IN
CAUTION: Wide open throttle operation in low
gears, before engine break-in period is complete,
can damage engine.
After first starting a new engine, allow it to idle for
15 seconds before shifting into a drive gear. Also:
²Drive the vehicle at varying speeds less than 88
km/h (55 mph) for the first 480 km (300 miles).
²Avoid fast acceleration and sudden stops.
²Do not drive at full-throttle for extended periods of
time.
²Do not drive at constant speeds.
²Do not idle the engine excessively.
A special break-in engine oil is not required. The
original engine oil installed is a high quality, energy
conserving lubricant. Special break-in oils are not
recommended. These oils could interfere with the
normal piston ring seating process.
New engines tend to consume more fuel and oil un-
til after the break-in period has ended.
ENGINE OIL
WARNING: NEW OR USED ENGINE OIL CAN BE IR-
RITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER.
DO NOT WASH SKIN WITH GASOLINE, DIESEL
FUEL, THINNER, OR SOLVENTS, HEALTH PROB-
LEMS CAN RESULT.
DO NOT POLLUTE, DISPOSE OF USED ENGINE
OIL PROPERLY. CONTACT YOUR DEALER OR GOV-
ERNMENT AGENCY FOR LOCATION OF COLLEC-
TION CENTER IN YOUR AREA.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase lu-
bricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
Use an engine oil that is API Service Grade Certi-
fied or an oil that conforms to the API Service Grade
SH or SH/CD. MOPAR provides engine oils that con-
form to all of these service grades.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity grade of engine oil. SAE 30 specifies a single
viscosity engine oil. Engine oils also have multiple
viscosities. These are specified with a dual SAE vis-
cosity grade which indicates the cold-to-hot tempera-
ture viscosity range. Select an engine oil that is best
suited to your particular temperature range and vari-
ation (Fig.1).
ENERGY CONSERVING OIL
An Energy Conserving type oil is recommeded for
gasoline engines. They are designated as either EN-
ERGY CONSERVING or ENERGY CONSERVING
II.
Fig. 1 Temperature/Engine Oil Viscosity
JLUBRICATION AND MAINTENANCE 0 - 15

CONTAINER IDENTIFICATION
Standard engine oil identification notations have
been adopted to aid in the proper selection of engine
oil. The identifying notations are located on the label
of engine oil plastic bottles and the top of engine oil
cans (Fig. 2).
ENGINE OIL ADDITIVES
In some instances, such as infrequent operation,
short trip driving, and during break-in after a major
overhaul, addition of special materials containing an-
ti-rust and anti-scuff additives are beneficial. A suit-
able product for this purpose is MOPAR Engine Oil
Supplement.
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator (Dipstick) is located
at the right rear of both 2.5L engines and 4.0L en-
gines (Fig. 3).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
Inspect engine oil level approximately every 800 ki-
lometers (500 miles). Unless the engine has exhibited
loss of oil pressure, run the engine for about five
minutes before checking oil level. Checking engine oil
level on a cold engine is not accurate.
To ensure proper lubrication of an engine, the en-
gine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick (Fig. 4
and 5).
(1) Position vehicle on level surface.
(2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading (Figs.4 and 5).
(6) Add oil only if level is below the ADD mark on
dipstick.
ENGINE OIL CHANGE AND FILTER REPLACEMENT
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals
described in Maintenance Schedules.
TO CHANGE ENGINE OIL
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Hoist and support vehicle on safety stands. Re-
fer to Hoisting and Jacking Recommendations in this
group.
Fig. 2 API Certification Mark
Fig. 3 Engine Oil Dipstick LocationÐTypical
Fig. 4 Engine Oil DipstickÐ2.5L Engine
0 - 16 LUBRICATION AND MAINTENANCEJ

(3) Remove oil fill cap.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan. Inspect drain plug threads for
stretching or other damage. Replace drain plug and
gasket if damaged.
(6) Install drain plug in crankcase.
(7) Lower vehicle and fill crankcase with specified
type and amount of engine oil described in this sec-
tion.
(8) Install oil fill cap.
(9) Start engine and inspect for leaks.
(10) Stop engine and inspect oil level.
ENGINE OIL FILTER
FILTER SPECIFICATION
CAUTION: Do not use oil filter with metric threads.
The proper oil filter has SAE type 3/4 X 16 threads.
An oil filter with metric threads can result in oil
leaks and engine failure.
All Jeep engines are equipped with a high quality
full-flow, throw-away type oil filter. Chrysler Corpo-
ration recommends a Mopar or equivalent oil filter be
used.
OIL FILTER REMOVAL
(1) Position a drain pan under the oil filter.
(2) Using a suitable oil filter wrench loosen filter.
(3) Rotate the oil filter counterclockwise to remove
it from the cylinder block oil filter boss (Fig. 6 and 7).
(4) When filter separates from adapter nipple, tip
gasket end upward to minimize oil spill. Remove fil-
ter from vehicle.
(5) With a wiping cloth, clean the gasket sealing
surface (Fig. 8) of oil and grime.
OIL FILTER INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil or chassis grease.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 8) hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start en-
gine. Inspect for oil leaks.
Fig. 5 Engine Oil Dipstick Ð 4.0L EngineFig. 6 Oil FilterÐ2.5L Engine
Fig. 7 Oil Filter Ð 4.0L Engine
Fig. 8 Oil Filter Sealing SurfaceÐTypical
JLUBRICATION AND MAINTENANCE 0 - 17

USED ENGINE OIL DISPOSAL
Care should be exercised when disposing used en-
gine oil after it has been drained from a vehicle en-
gine. Refer to the WARNING listed above.
ENGINE COOLING SYSTEM
WARNINGS AND PRECAUTIONS
WARNING: ANTIFREEZE IS AN ETHYLENE GLYCOL
BASE COOLANT AND IS HARMFUL IF SWAL-
LOWED OR INHALED. IF SWALLOWED, DRINK
TWO GLASSES OF WATER AND INDUCE VOMIT-
ING. IF INHALED, MOVE TO FRESH AIR AREA.
SEEK MEDICAL ATTENTION IMMEDIATELY. DO NOT
STORE IN OPEN OR UNMARKED CONTAINERS.
WASH SKIN AND CLOTHING THOROUGHLY AFTER
COMING IN CONTACT WITH ETHYLENE GLYCOL.
KEEP OUT OF REACH OF CHILDREN.
DISPOSE OF GLYCOL BASE COOLANT PROP-
ERLY, CONTACT YOUR DEALER OR GOVERNMENT
AGENCY FOR LOCATION OF COLLECTION CENTER
IN YOUR AREA.
DO NOT OPEN A COOLING SYSTEM WHEN THE
ENGINE IS AT RUNNING TEMPERATURE, PER-
SONAL INJURY CAN RESULT.
AVOID RADIATOR COOLING FAN WHEN ENGINE
COMPARTMENT RELATED SERVICE IS PER-
FORMED, PERSONAL INJURY CAN RESULT.
CAUTION: Do not use straight antifreeze as engine
coolant, inadequate engine running temperatures
can result.
Do not operate vehicle without proper concentra-
tion of recommended ethylene glycol coolant, high
running temperatures and cooling system corrosion
can result.
The engine cooling system will develop internal
pressure of 97 to 123 kPa (14 to 18 psi) at normal op-
erating temperature. Allow the vehicle approximately
one half hour to cool off before opening the cooling
system. As an indicator of pressure, squeeze the up-
per radiator hose between index finger and thumb. If
it collapses with little effort the system would have
low internal pressure and should be safe to open to
the first safety notch of the radiator cap. Refer to
Group 7, Cooling System.
COOLING SYSTEM INSPECTION
Coolant level should be inspected when other en-
gine compartment service is performed or when cool-
ant leak is suspected. With the engine at normal
operating temperature, observe the coolant level in
thecoolant recovery bottle. The coolant level mustbe at least above the ADD mark and preferably at
the FULL mark. Add coolant to the coolant recovery
bottleonly, if necessary.
Cooling system freeze protection should be tested
at the onset of the winter season or every 12 months.
Service is required if coolant is low, contaminated,
rusty or freeze protection is inadequate. To properly
test cooling system, see Group 7, Cooling System.
The cooling system factory fill is a mixture of 50%
Ethylene Glycol based antifreeze and 50% water. Us-
ing a suitable hydrometer, measure antifreeze con-
centration in the radiator when the engine is cool. If
the cooling system has recently been serviced, allow
coolant to circulate for at least 20 minutes before
taking hydrometer reading. Properly mixed coolant
will protect the cooling system to -37ÉC (-35ÉF). If the
freeze protection is above -28ÉC (-20ÉF), drain enough
coolant from the cooling system to allow room to add
antifreeze to achieve adequate protection. A mix table
on the coolant container indicates the amount of an-
tifreeze required to winterize the cooling system
based on the capacity, see Capacity Chart in General
Information section of this group.
ANTIFREEZE SPECIFICATION
Chrysler Corporation recommends the use of Mo-
par Antifreeze/Coolant or a high quality, ethylene
glycol base antifreeze/coolant, with a silicate inhibi-
tor.
COOLING SYSTEM SERVICE
The cooling system should be drained, flushed and
filled with the proper coolant mixture at the inter-
vals described in the Lubrication and Maintenance
Schedules. Refer to General Information section of
this group. For proper service instructions see Group
7, Cooling System.
AIR CLEANER ELEMENT
The air cleaner element should be serviced at the
intervals described in the Lubrication and Mainte-
nance Schedules sections of this group. Additional in-
formation can be found in Group 14, Fuel System
and Group 25, Emission System. Inspect all air
cleaner hoses or tubes for damage or leaks when
other engine compartment service is performed. Re-
place faulty components.
FILTER ELEMENT SERVICE/REPLACEMENT
CAUTION: The air cleaner cover must be installed
properly for the emissions system and engine con-
troller to function correctly.
Do not immerse paper air filter element in clean-
ing solvents, damage can result.
(1) Remove the air cleaner cover from the body/
housing (Fig. 9).
0 - 18 LUBRICATION AND MAINTENANCEJ

(2) Remove the air cleaner element from the body/
housing.
(3) Hold a shop light on throttle body side of ele-
ment. Inspect air intake side of element. If element
is saturated with oil or light is not visible, replace fil-
ter. If element is saturated with oil, perform crank-
case ventilation system tests.
(4) Wash the air cleaner cover and body/housing
(Fig. 10) with cleaning solvent and wipe dry.
(5) Install the air cleaner element and attach the
cover to the body/housing.
CRANKCASE VENTILATION SYSTEM
All Jeep 2.5L and 4.0L engines are equipped with a
crankcase ventilation (CCV) system. Refer to Group
25 Emissions, for additional information.
FUEL FILTER
The fuel filter requires service only when a fuel
contamination problem is suspected. For proper diag-
nostic and service procedures refer to Group 14, Fuel
System.
FUEL USAGE STATEMENTÐGAS ENGINES
Jeep vehicles are designed to meet all emission reg-
ulations and provide excellent fuel economy using
high quality unleaded gasoline. Only use unleaded
gasolines having a minimum posted octane of 87.
If a Jeep vehicle develops occasional light spark
knock (ping) at low engine speeds, this is not harm-
ful. However,continued heavy knock at high
speeds can cause damage and should be
checked immediately.
In addition to using unleaded gasoline with the
proper octane rating,those that contain deter-
gents, corrosion and stability additives are rec-
ommended.Using gasolines that have these
additives will help improve fuel economy, reduce
emissions and maintain vehicle performance.
Poor quality gasolinecan cause problems such
as hard starting, stalling and stumble. If these prob-
lems occur, use another brand of gasoline before con-
sidering servicing the vehicle.
GASOLINE/OXYGENATE BLENDS
Some fuel suppliers blend unleaded gasoline with
materials that contain oxygen such as alcohol, MTBE
and ETBE. The type and amount of oxygenate used
in the blend is important. The following are generally
used in gasoline blends:
ETHANOL
Ethanol (Ethyl or Grain Alcohol) properly blended,
is used as a mixture of 10 percent ethanol and 90
percent gasoline.Gasoline with ethanol may be
used in your vehicle.
METHANOL
CAUTION: Do not use gasolines containing metha-
nol. Use of methanol/gasoline blends may result in
starting and driveability problems. In addition, dam-
age may be done to critical fuel system compo-
nents.
Methanol (Methyl or Wood Alcohol) is used in a va-
riety of concentrations blended with unleaded gaso-
Fig. 9 Air Cleaner & Filter ElementÐ2.5L and 4.0L
Engines
Fig. 10 Air Cleaner Body/Housing & Cover
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