1995 JEEP YJ 2.5 engine

FLUID CAPACITIES
Fuel Tank
XJ .....................................................76.4 L (20.2 gal.)
YJ(Standard) ......................................56.8 L (15 gal.)
YJ(Optional) .......................................75.7 L (20 gal.)
Engine Oil
2.5L ......................................................3.8 L (4.0 qts.)
4.0L ......................................................5.7 L (6.0 qts.)
Cooling System
2.5L(XJ).............................................9.5 L* (10 qts.*)
2.5L(YJ) ........................................8.5 L** (9.0 qts.**)
4.0L(XJ) ........................................11.4 L* (12.0 qts.*)
4.0L(YJ) ......................................9.9 L** (10.5 qts.**)
* Includes (2.2 L) (2.3 qts) for coolant recovery res-
ervoir.
** Includes (0.9 L) (1.0 qt.) for coolant recovery res-
ervoir.
Automatic Transmission
Dry fill capacity.*
AW4 (XJ-4.0L) ...................................8.0 L (16.9 pts.)
30RH (YJ-2.5L) .................................8.2 L (17.5 pts.)
32RH (YJ-4.0L) .................................8.2 L (17.5 pts.)
*Depending on type and size of internal cooler,
length and inside diameter of cooler lines, or use ofan auxiliary cooler, these figures may vary. Refer to
Group 21, Transmission for proper fluid fill proce-
dure.
Manual Transmission
AX4/5 (4X2) .........................................3.3 L (3.5 qts.)
AX5 (4X4) ............................................3.2 L (3.3 qts.)
AX15 (4X2) ..........................................3.1 L (3.2 qts.)
AX15 (4X4) ......................................3.15 L (3.32 qts.)
Fill to bottom of fill hole.
Transfer Case
SELEC-TRAC 242(XJ) .......................1.4 L (3.0 pts.)
COMMAND-TRAC 231(XJ) ...............1.0 L (2.2 pts.)
COMMAND-TRAC 231(YJ-Man Trans) ..1.5 L (3.25
pts.)
COMMAND-TRAC 231(YJ-Auto Trans) ....1.0 L (2.2
pts.)
Front Axle
MODEL 30 (YJ) ..............................1.65 L (3.76 pts.)
MODEL 30 (XJ) ..............................1.48 L (3.13 pts.)
Rear Axle
MODEL 35 (XJ-YJ) ........................1.6 L (3.38 pts.*)
8-1/4 (XJ) .........................................2.08 L (4.4 pts.*)
* When equipped with TRAC-LOK, include 2
ounces of Friction Modifier Additive.
JLUBRICATION AND MAINTENANCE 0 - 3

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

(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
JLUBRICATION AND MAINTENANCE 0 - 19

line. You may encounter fuels containing 3 percent or
more methanol along with other alcohols called cosol-
vents.
Problems that are the result of using methanol/gas-
oline blends are not the responsibility of Chrysler
Corporation. They may not be covered by the vehicle
warranty.
MTBE/ETBE
Gasoline and MTBE (Methyl Tertiary Butyl Ether)
blends are a mixture of unleaded gasoline and up to
15 percent MTBE. Gasoline and ETBE (Ethyl Ter-
tiary Butyl Ether) are blends of gasoline and up to
17 percent ETBE. Gasoline blended with MTBE or
ETBE may be used.
CLEAN AIR GASOLINE
Many gasolines are now being blended that con-
tribute to cleaner air, especially in those areas of the
country where air pollution levels are high. These
new blends provide a cleaner burning fuel and some
are referred to asReformulated Gasoline.
In areas of the country where carbon monoxide lev-
els are high, gasolines are being treated with oxygen-
ated materials such as MTBE, ETBE and ethanol.
Chrysler Corporation supports these efforts toward
cleaner air and recommends the use of these gaso-
lines as they become available.
IGNITION CABLES, DISTRIBUTOR CAP AND
ROTOR
Inspect and test ignition cables, distributor cap and
rotor when the spark plugs are replaced. Oil and
grime should be cleaned from the ignition cables and
distributor cap to avoid possible spark plug fouling.
Mopar Foamy Engine Degreaser or equivalent is rec-
ommended for cleaning the engine compartment. For
proper service and diagnostic procedures refer to
Group 8D, Ignition System.
IGNITION TIMING
The ignition timing for 2.5L and 4.0L engines is
not adjustable. Refer to the specifications listed on
the engine Emission Control Information Label. Re-
fer to Group 25, Emission Control Systems for addi-
tional information.
SPARK PLUGS
Ignition spark plugs should be replaced at the
mileage interval described in the Lubrication and
Maintenance Schedules. Refer to the General Infor-
mation section of this group. For proper service pro-
cedures refer to Group 8D, Ignition Systems.
BATTERY
WARNING: WEAR SAFETY GLASSES, RUBBER
GLOVES AND PROTECTIVE CLOTHING WHEN HAN-DLING/SERVICING A BATTERY. THE BATTERY
ELECTROLYTE CONTAINS SULFURIC ACID AND
WILL CAUSE HARM IF IT CONTACTS SKIN, EYES
OR CLOTHING. IT WILL ALSO DAMAGE PAINTED
(AS WELL AS UN-PAINTED) SURFACES OF A VEHI-
CLE. IF SULFURIC ACID CONTACTS ANY OF
THESE, FLUSH IMMEDIATELY WITH LARGE
AMOUNTS OF WATER. IF SULFURIC ACID CON-
TACTS SKIN OR EYES, GET IMMEDIATE MEDICAL
ATTENTION. DO NOT SMOKE IN THE VICINITY OF A
BATTERY. KEEP OPEN FLAMES AND SPARKS
AWAY FROM BATTERY FILLER CAPS BECAUSE
EXPLOSIVE GAS IS ALWAYS PRESENT.
Inspect battery tray, hold down and terminal con-
nections when other under hood service is performed.
For proper diagnostic procedures refer to Group 8A,
Battery/Starting/Charging System Diagnostics. For
service and cleaning procedures refer to Group 8B,
Battery/Starter Service.
Care should be taken when disposing a bat-
tery after removal from a vehicle. Lead-acid
batteries are highly poisonous and, when indis-
criminately disposed, could create a problem
for the environment. Contact the applicable lo-
cal city or county government agency to deter-
mine where automobile (lead-acid) batteries
can be properly disposed in the local area.
RUBBER AND PLASTIC COMPONENT INSPECTION
CAUTION: Plastic hoses or wire harness covers will
melt or deform when exposed to heat from exhaust
system or engine manifolds.
Position plastic or rubber components away from
moving parts in engine compartment or under vehi-
cle, or damage will result.
Do not allow rubber engine mounts or other com-
ponents to become oil contaminated, repair cause
of oil contamination and clean area.
All rubber and plastic components should be in-
spected when engine compartment or under vehicle
service is performed. When evidence of deterioration
exists, replacement is required. To reduce deteriora-
tion of rubber components, Chrysler Corporation rec-
ommends Mopar Foamy Engine Degreaser or
equivalent be used to clean engine compartment of
oil and road grime.
EMISSION CONTROL SYSTEM
Inspect all emission control components and hoses
when other under hood service is performed. Refer to
emission system Vacuum Hose Label located on the
inside of the hood in the engine compartment and
Group 25, Emission Control Systems for proper ser-
vice procedures.
0 - 20 LUBRICATION AND MAINTENANCEJ

(5) Inspect the reservoir rubber diaphragm seal for
cracks, cuts and distortion.
(6) Inspect the brake fluid tubing fittings and the
master cylinder housing for indications of fluid leak-
age. Repair as necessary.
(7) Install the brake fluid reservoir cover.
ANTI-LOCK BRAKE SYSTEMÐXJ VEHICLES
The anti-lock brake system fluid reservoir for XJ
Vehicles is located in the engine compartment at the
left side of the dash panel.
(1) Turn the ignition switch ON and allow the
pump motor to operate until it automatically de-en-
ergizes.
(2) Clean the cover before removing it.
CAUTION: Over-filling could cause fluid overflow
and possible reservoir damage when the pump mo-
tor energizes.
(3) The brake fluid level should be no lower than
the ADD indicator on the side of the reservoir (Fig.
8). If not, add brake fluid as necessary. Raise the
fluid level to the FULL indicator only. Do not over-fill
the reservoir.
(4) Turn the ignition switch OFF.
BRAKE SYSTEM INSPECTION
A brake system inspection should be included with
all brake service procedures, and also each time the
vehicle is lubricated.
(1) Inspect the brake pads and linings for excessive
wear, cracks, charred surfaces and broken rivets.
(2) Inspect brake pads and linings for contamina-
tion from brake fluid, and/or other fluids.
(3) Replace the brake pads linings if they are worn
to within 0.78 mm (1/32 in) of the rivet head.
(4) Operate the rear brake self-adjuster lever and
pivot. Test the operation of the self-adjuster screw for
ease of movement.
(5) Inspect the self-adjuster components for wear
or damage.
(6) Inspect the disc brake caliper dust boot for
damage and indications of brake fluid leakage. In-
spect the bushings and pins for corrosion, tears and a
binding condition.
(7) Pull the rear wheel cylinder dust boot back to
expose the wheel cylinder housing. Inspect for fluid
leaks. Inspect the pistons and cylinder bores.
(8) Inspect the brake differential warning valve
and housing for indications of leakage.
BRAKE FLUID HOSES/TUBING
The rubber brake fluid hoses should be inspected
for:
²Correct length
²Severe surface cracking
²Swelling
²Pulling
²Scuffing
²Excessively worn areas
If the hose has cracks or abrasions in the rub-
ber cover, the hose should be replaced.
(1) Inspect all the hoses for kinks, a distorted con-
dition and fluid leakage.
(2) Inspect the hose and tubing routing under the
vehicle. Verify that no hose/tubing is rubbing against
any exhaust or other underbody components.
PARKING BRAKE
(1) Engage the parking brake pedal and then re-
lease it.
(2) Test it for smooth operation and vehicle-holding
capability.
(3) Inspect the parking brake cables.
(4) With the parking brake released, the rear
wheels should
rotate without restriction. Adjust the parking brake
cable tension, if necessary (Fig. 9 and 10).
(5) Repair any parking brake malfunctions.
BRAKE OPERATIONAL TEST
(1) Drive the vehicle and test for proper brake ac-
tion.
Fig. 7 Reservoir Fluid LevelÐYJ (2.5L)
Fig. 8 Reservoir Fluid LevelÐYJ-XJ and Anti-Lock
Brake System
JLUBRICATION AND MAINTENANCE 0 - 31

(4) Position clutch disc on flywheel. Be sure side of
disc marked flywheel side is positioned against fly-
wheel (Fig. 2). If disc is not marked, be sure flat side
of disc hub is toward flywheel.
(5) Inspect condition of pressure plate surface of
clutch cover (Fig. 2). Replace cover if this surface is
worn, heat checked, cracked, or scored.
(6) Insert clutch alignment tool in clutch disc (Fig.
3).
(7) Insert alignment tool in pilot bearing and posi-
tion disc on flywheel. Be sure disc hub is positioned
correctly. Side of hub marked Flywheel Side should
face flywheel (Fig. 2). If disc is not marked, place flat
side of disc against flywheel.
(8) Position clutch cover over disc and on flywheel
(Fig. 3).
(9) Install clutch cover bolts finger tight.(10) Tighten cover bolts evenly and in rotation a
few threads at a time.Cover bolts must be tight-
ened evenly and to specified torque to avoid
distorting cover. Tightening torques are 31 Nzm
(23 ft. lbs.) on 2.5L engines and 54 Nzm (40 ft.
lbs.) on 4.0L engines.
(11) Apply light coat of Mopar high temperature
bearing grease to pilot bearing hub and splines of
transmission input shaft.Do not overlubricate
shaft splines. This will result in grease contam-
ination of disc.
(12) Install transmission (Figs. 4 and 5). Refer to
procedures in Group 21.
RELEASE BEARING REPLACEMENT
(1) Remove transmission as described in Group 21.
Fig. 2 Clutch Disc And Pressure Plate InspectionFig. 3 Typical Method Of Aligning Clutch Disc
Fig. 4 Manual Transmission Mounting (4.0L)
JCLUTCH SERVICE 6 - 11

Fig. 1 Coolant FlowÐXJ Models with 2.5L 4-Cylinder EngineÐTypical
Fig. 2 Coolant FlowÐYJ Models with 2.5L 4-Cylinder EngineÐTypical
7 - 2 COOLING SYSTEMJ