
ROUTINE SERVICE
The following routine vehicle service is highly rec-
ommended on a monthly basis.
TIRESÐInspect the tires for unusual wear/damage
and determine if the inflation pressure is acceptable
for the vehicle load.
BATTERYÐInspect and clean the terminals.
Tighten the terminals, if necessary.
FLUIDSÐDetermine if the coolant, brake fluid,
power steering, automatic transmission, and clutch
fluid level are acceptable. Add fluid, if necessary.
LIGHTS/ELECTRICALÐTest all the electrically
operated systems in the vehicle for proper operation.
It is also recommended that the engine oil level
and the windshield washer fluid level be deter-
mined (and corrected) during each fuel fill-up.
FUEL REQUIREMENTS
All Jeeptengines require the use of unleaded gas-
oline. In addition, the fuel must have a minimum oc-
tane rating of 87.
CAUTION: UNLEADED FUEL ONLY must be used in
vehicles equipped with a catalyst emission control
system. All vehicles have reminders printed on the
instrument panel (Fig. 1) and on the fuel filler door
(Fig. 2). Vehicles also have fuel filler tubes that are
designed to accept only the small-diameter un-
leaded gasoline nozzles. It is illegal to defeat the
design of an unleaded fuel filler tube.
CLASSIFICATION OF LUBRICANTS
Lubricating fluids and chassis component lubri-
cants are classified and graded according to stan-
dards recommended by the:
²Society of Automotive Engineers (SAE),²American Petroleum Institute (API), and
²National Lubricating Grease Institute (NLGI).
ENGINE OIL
SAE VISCOSITY GRADE
An SAE viscosity grade is used to specify viscosity
of engine oil. SAE 30 specifies a single viscosity en-
gine oil. Engine oils also have multiple viscosities
(Fig. 3).
The viscosity grade of an oil is an indicator of its
thickness or flow capability. The lower the number,
the better the flow. The second viscosity grade num-
ber (without a W suffix) is the warm/hot-temperature
viscosity. The viscosity increases with engine temper-
ature. With a single viscosity grade, the oil viscosity
is valid only for one narrow temperature range.
Fig. 1 Unleaded Fuel Only RemindersÐFuel Gauge
Fig. 2 Unleaded Fuel Only ReminderÐFuel Filler
Door
Fig. 3 SAE Oil Viscosity Grade & API Service Grade
0 - 2 LUBRICATION AND MAINTENANCEJ

Above that temperature range the viscosity will de-
crease, and below that range the viscosity will in-
crease.
An engine oil with an SAE 5W-30 viscosity grade
provides good flow capability for fast cold weather
engine starts. The viscosity will then increase with
engine temperature to provide good high-tempera-
ture engine lubrication.
API SERVICE GRADE
The API Service Grade specifies the type of engine/
operating conditions for which the oil is intended.
The API Service Grade specifications also apply to
energy conserving engine oils (Fig. 3). The API cer-
tification mark is also used indicating that the oil is
certified to meet the most critical requirements es-
tablished by the manufacturer (Fig. 4).
For maximum protection, use API Service Grade
SG, SG/CD or SG/CE engine oil in Jeeptengines.
GEAR LUBRICANTS
A dual SAE viscosity grade is also used to specify
the viscosity of multipurpose gear lubricants.
The API lubrication quality grade designation
identifies gear lubricants in terms of recommended
usage.
CHASSIS COMPONENT AND WHEEL BEARING
LUBRICANTS
The chassis component and wheel bearing lubri-
cants are identified by the NLGI Certification Sym-
bol (Fig. 5).
The letterGindicates wheel bearing lubricant and
the letterLindicates chassis lubricant. When the
letters are combined the lubricant can be used for
dual applications. The suffix lettersCandBindi-
cates quality level of the lubricant. Use only lubri-
cants that display the NLGI Certification Symbol.
RECOMMENDED LUBRICANT AND REPLACEMENT
PARTS
Jeeptvehicles are engineered to provide many
years of dependable operation. When necessary,MO-
PAR brand lubricants and genuine replacement
partsare highly recommended.
COMPONENTS REQUIRING NO LUBRICATION
There are many components that should not be lu-
bricated. The components that shouldnotbe lubri-
cated are:
²air pumps;
²generator bearings;
²drive belts;
²drive belt idler pulleys;
²rubber bushings;
²starter motor bearings;
²suspension strut bearings;
²throttle control cables;
²throttle linkage ball joints; and
²water pump bearings.
Fig. 4 The API Engine Oil Certification Mark
Fig. 5 NLGI Lubricant Certification/Identification
Symbol
JLUBRICATION AND MAINTENANCE 0 - 3

ENGINE MAINTENANCE
INDEX
page page
Accessory Drive Belt...................... 20
Air-Conditioner Compressor/Hoses/Fittings...... 21
Battery................................ 18
Cooling System.......................... 16
Crankcase Ventilation System............... 17
Engine Air Cleaner Filter Element............ 16
Engine Break-In......................... 13
Engine Oil.............................. 13Engine Oil Change and Filter Replacement..... 15
Engine Oil Filter......................... 14
Engine Supports......................... 20
Exhaust System......................... 20
Fuel Usage StatementÐGas Engines......... 17
Ignition Cables, Distributor Cap and Rotor...... 18
Rubber and Plastic Ducts/Hoses/Tubing....... 19
Spark Plugs............................ 18
ENGINE BREAK-IN
After first starting a new engine, allow it to idle
and warm up for at least 15 seconds before shifting
the transmission into a drive gear.
Drive the vehicle at:
²varying speeds less than 80 km/h (50 mph) for the
first 160 km (100 miles), and
²speeds less than 88 km/h (55 mph) for the first 800
km (500 miles).
Avoid driving at full-throttle for extended periods
of time. Also, avoid fast acceleration and sudden
stops.
A special break-in engine oil is not required. The
original oil installed in a vehicle is a quality lubri-
cant. There is no requirement to have the oil
changed or the oil filter replaced until the first
scheduled maintenance interval.
The engine oil, coolant and all the other engine re-
lated fluid levels should be determined on a regular
basis.
ENGINE OIL
SPECIFICATIONS
API SERVICE GRADE
For maximum engine protection during all driving
conditions, install an engine oil that conforms to API
Service Grade. MOPAR Engine Oil conforms to all of
these API Service Grades.
SAE VISCOSITY
SAE designated multi-viscosity grade engine oil is
to protect engines. This type of engine oil can usually
be installed and remain in the engine until the next
scheduled oil change. Select the engine oil viscosity
according to the lowest ambient air temperature ex-
pected before the next scheduled oil change (Fig.1).
Low viscosity engine oil allows easier engine starting
during cold weather. SAE 5W-30 viscosity engine oil
is recommended when the ambient air temperatures
consistently decrease to below 10ÉF (-12ÉC).ENERGY CONSERVING OIL
In selecting the correct API grade and SAE grade,
anENERGY CONSERVINGtype engine oil is also
recommended.
CONTAINER IDENTIFICATION
Standard engine oil notations have been adopted
for selection of engine oil. The notations are located
on side of plastic bottles and on the top of engine oil
cans (Fig. 2).
²The top, outer field contains theAPI Service
Gradenotation for the engine oil.
Fig. 1 Temperature/Engine Oil Viscosity
Fig. 2 Engine Oil Container Standard Notations
JLUBRICATION AND MAINTENANCE 0 - 13

ENGINE OIL CHANGE AND FILTER REPLACEMENT
WARNING: CARE SHOULD BE TAKEN WHEN
CHANGING OIL. PROTECTIVE CLOTHING AND
GLOVES SHOULD BE WORN. EXPOSED SKIN
SHOULD BE WASHED WITH SOAP AND WATER TO
REMOVE ANY ENGINE OIL. DO NOT USE GASO-
LINE, THINNER, OR SOLVENTS TO REMOVE EN-
GINE OIL FROM SKIN.
REQUIRED MAINTENANCE
With normal driving conditions, engine oil and fil-
ter must be changed after each 12 000-km (7,500-
miles)/12-month interval. If the vehicle is involved
with a severe driving condition, after each 4 800-km
(3,000-miles)/3-month interval. A severe driving con-
dition includes:
²frequent short trip driving less than 24 km (15
miles);
²frequent driving in a dusty environment;
²trailer towing;
²extensive engine idling;
²sustained high-speed operation;
²desert operation;
²frequent starting and stopping;
²cold-climate operation;
²off-road driving; or
²commercial service.
OIL CHANGE AND FILTER REPLACEMENT
(1) Drain the engine oil from the crankcase. Wait
until after the engine has attained the normal oper-
ating temperature to ensure complete drainage of oil.
(2) Install the drain-hole plug with a replacement
gasket.
The oil filter should be replaced during every
engine oil change.
(3)
Rotate the oil filter counterclockwise to remove
it from the cylinder block oil filter boss (Figs. 6 and 7).
(4) Clean the cylinder block oil filter boss.
(5) Apply a light coat of engine oil to the rubber
seal on the replacement oil filter.
CAUTION: Do not use oil filter with metric threads.
The proper oil filter has SAE type 3/4 X 16 threads.
The use of an oil filter with metric threads can re-
sult in engine oil leaks and engine failure.
(6) Install andhand tightenthe oil filter 1/2 to
3/4 of-a-turn clockwise beyond the point where the
seal first contacts the cylinder block.
(7) Add engine oil in fill hole located on top of en-
gine cylinder head cover (Fig. 8).
(8) Observe the oil level on the dipstick. Add oil,
if necessary, to increase the level to the FULL mark.
Fig. 6 Oil Filter RemovalÐ2.5L Engine
Fig. 7 Oil FilterÐ4.0L Engine
Fig. 8 Adding Engine OilÐTypical
JLUBRICATION AND MAINTENANCE 0 - 15

CAUTION: Do not overfill the engine crankcase with
oil. This will cause oil aeration and result in a de-
crease in the engine oil pressure.
(9) Start the engine and observe the oil pressure
gauge or warning lamp. If the pressure does not in-
crease or the warning lamp does not go out, stop the
engine and determine the cause of the problem.
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.
COOLING SYSTEM
WARNING: USE EXTREME CAUTION WHEN RE-
MOVING THE RADIATOR CAP IF THE ENGINE IS
OPERATING. DO NOT PUT YOUR HANDS NEAR
THE DRIVE BELT(S), PULLEYS OR FAN BLADE. DO
NOT STAND IN A DIRECT LINE WITH THE FAN
BLADE.
RECOMMENDED MAINTENANCE
The engine coolant level should be determined at
least once a month and more often during periods of
hot weather. Add coolant as necessary.
COOLANT LEVEL
With the engine at normal operating temperature,
observe the coolant level in thecoolant recovery bot-
tle. The coolant level must be at least above the ADD
mark and preferably at the FULL mark. Add coolant
to the coolant recovery bottleonly, if necessary.
REQUIRED MAINTENANCE
Check coolant level, and inspect condition of cool-
ing system hoses and clamps after each 12 000-km
(7,500-miles).
Initially, coolant must be drained and cooling sys-
tem flushed and filled after the first 36 months of op-
eration. Thereafter, after each 24-months interval of
vehicle operation.
RECOMMENDED MAINTENANCE
The engine cooling system should be inspected for
proper operation and for component failure at least
every 12 months.
WARNING: IF THE ENGINE HAS BEEN RECENTLY
OPERATED, USE EXTREME CARE WHEN REMOV-
ING THE RADIATOR CAP TO AVOID SCALDING
WITH HOT, PRESSURIZED COOLANT.
For additional information, refer to Section 7, Cool-
ing System.COOLANT FREEZE PROTECTION
Jeeptcooling systems contain a 50/50 mixture of
anti-freeze and distilled water coolant. This is the
recommended coolant mixture for most ambient tem-
peratures. The factory-installed anti-freeze is formu-
lated to prevent corrosion on all cooling system metal
surfaces.
The degree of coolant freeze protection should be
tested every 12 months. If the coolant is contami-
nated orrustyin appearance, cooling system should
be drained and filled with a 50/50 mixture of fresh
coolant. For additional information, refer to Group
7ÐCooling System.
ENGINE AIR CLEANER FILTER ELEMENT
RECOMMENDED MAINTENANCE
Engine performance and fuel economy can be af-
fected by a restricted air cleaner filter. The filter
should be inspected on a regular basis for excessive
air restriction.
If the filter element is saturated with oil, replace
the filter element.
REQUIRED MAINTENANCE
Engine air cleaner filter must be replaced after
each 48 000-km (30,000-miles).
If a vehicle is frequently operated in dusty
areas, the air cleaner filter should be inspected
often.
FILTER ELEMENT SERVICE/REPLACEMENT
(1) Remove the air cleaner cover from the body/
housing (Fig. 9).
(2) Remove the air cleaner filter element from the
body/housing.
Fig. 9 Air Cleaner & Filter ElementÐ2.5L and 4.0L
Engines
0 - 16 LUBRICATION AND MAINTENANCEJ

DRAINING ATF/FILTER REMOVAL
Drain the automatic transmission fluid (ATF) im-
mediately after stopping the engine (before the ATF
cools).
(1) Raise and support the vehicle.
(2) Loosen the transmission pan bolts and drain
the original ATF into an appropriate container. Re-
move the pan bolts, the pan and the gasket.
Care should be exercised when disposing used
ATF after it has been drained from a vehicle
transmission.
(3) Remove the screws and the ATF filter (Fig. 8).
Discard the filter.
FILTER INSTALLATION/ATF RE-FILL
(1) Install a replacement ATF filter. Tighten the
screws with 4 NIm (35 in. lbs.) torque.
(2) Clean the pan thoroughly. Install a replace-
ment gasket on the pan. Install the pan with the at-
taching bolts:
²model AW-4 transmission Ð tighten the pan bolts
with 7 NIm (60 in. lbs.) torque; and
²model 998 transmission Ð tighten the pan bolts
with 17 NIm (150 in. lbs.) torque.
(3) Remove the support and lower the vehicle.
(4) Pour approximately 4.7 liters (5 quarts) of ATF
into the filler tube. Use MerconŸ ATF for AW-4 au-
tomatic transmissions. Use MOPAR ATF PLUS type
7176 or equivalent, for 998 automatic transmissions.
(5) Place a block in front of and at the rear of one
wheel/tire to prevent vehicle movement.
(6) Start the engine and allow it to idle a few min-
utes.
(7) Apply the brake pedal and engage the parking
brake. Move the transmission selector lever through
all positions, then place the selector lever in NEU-
TRAL position.(8) With the transmission at normal operating
temperature, observe the ATF level on the dipstick.
Add ATF (if necessary) to raise the level to the
FULL mark on the dipstick.Only 0.5 liter (1.0 pint)
will raise the level from the ADD mark to the
FULL mark when the ATF is at normal operat-
ing temperature.
(9) Inspect for fluid leaks and correct as necessary.
(10) Remove the wheel/tire blocks.
TRANSFER CASE
RECOMMENDED MAINTENANCE
The fluid (ATF) level in transfer cases should be
determined at the same time as the engine oil is
changed and the oil filter is replaced. Add ATF as
necessary.
In addition, transfer case ATF should be changed
after each 48 000-km (30,000-miles) interval of vehi-
cle operation has elapsed.
FLUID SPECIFICATIONS
If it is necessary to add fluid to a transfer case (or
when the fluid is changed), use MOPAR ATF PLUS
type 7176 or an equivalent MerconŸ/Dexron IIŸ
ATF.
FLUID LEVEL
The transfer case fill-hole plug is located at the
rear of the housing (Fig. 9).
Determine the transfer case fluid (ATF) level ac-
cording to the following procedure.
(1) Raise and support the vehicle.
(2) Remove the fill-hole plug from the transfer
case. The ATF level should be at the bottom edge of
the fill hole. The level can be slightly below the bot-
tom edge of the fill hole if the fluid is cold.
Fig. 9 Transfer CaseÐTypical
Fig. 8 ATF FilterÐTypical
JLUBRICATION AND MAINTENANCE 0 - 25

(2) Depending on fluid temperature, if the level is
below the FULL HOT mark or the FULL COLD
mark on the dipstick, add power steering fluid.
(3) Install the cap on the reservoir.
MANUAL STEERING GEARÐYJ VEHICLES
RECOMMENDED MAINTENANCE
The manual steering gear should be inspected for
damage at the same time as the engine oil is
changed and the oil filter is replaced. Repair as nec-essary (refer to Group 19ÐSteering for additional in-
formation and service procedures).
POWER BRAKE SYSTEM
RECOMMENDED MAINTENANCE
The condition of the brake system should be in-
spected and the fluid level in the master cylinder
should be checked each time the brake system is ser-
viced. Add brake fluid and repair as necessary.
In addition, the brake system should be operation-
ally tested periodically to ensure that it is function-
ing normally.
FLUID SPECIFICATION
Jeeptpower brake systems require MOPAR
Heavy-Duty Brake Fluid, or an equivalent product
identified as conforming to FMVSS No. 116, DOT-3
and SAE J-1703 specifications.
Usenew brake fluid onlywhen adding fluid to
the reservoir, to fill the brake system. Never use re-
claimed fluid.
BRAKE FLUID LEVEL
STANDARD POWER BRAKE SYSTEM
(1) Clean the cover and the sides of the brake fluid
reservoir.
(2) Detach the bail retainer from the reservoir
cover and remove the cover from the reservoir.
(3) The brake fluid level should be 6 mm (1/4 in)
below the rim of each reservoir well for XJ and YJ
Vehicles (Fig. 7). If not, add brake fluid as necessary.
(4) Inspect the reservoir cover bail retainer for ten-
sion and the cover for proper fit. The cover should fit
tight and have a good seal.
Fig. 4 Power Steering SystemÐXJ Vehicles
Fig. 5 Power Steering SystemÐYJ Vehicles
Fig. 6 Power Steering Fluid Reservoir
DipstickÐTypical
0 - 32 LUBRICATION AND MAINTENANCEJ

Refer to Group 0, Lubrication and Maintenance for
additional information regarding temperature range,
viscosity and fluid level.
CAUTION: If the axle is submerged in water, the lu-
bricant must be replaced immediately to avoid the
possibility of premature axle failure.
DRIVE AXLE ASSEMBLY REPLACEMENTÐXJ
VEHICLES
REMOVAL
(1) Raise the vehicle and position support stands
under the frame rails slightly in behind the lower
suspension arm frame brackets.
(2) Remove the front wheels.
(3) Remove the brake components and ABS brake
sensor (if equipped). Refer to Group 5ÐBrakes.
(4) On 4WD vehicles, disconnect the axle vent
hose.
(5) On 4WD vehicles, mark the drive shaft yoke
and axle pinion yoke for alignment reference. Discon-
nect the drive shaft from the axle.
(6) Disconnect the stabilizer bar link at the axle
bracket.
(7) Disconnect the shock absorbers from axle
bracket.
(8) Disconnect the track bar from the axle bracket.
(9) Disconnect the tie rod and drag link from the
steering knuckle. Disconnect the steering dampener
from the axle bracket.
(10) Support the axle with a hydraulic jack under
the differential.
(11) Disconnect the upper and lower suspension
arms from the axle bracket.
(12) Lower the jack enough to remove the axle.
The coil springs will drop with the axle.
(13) Remove the coil springs from the axle bracket.
INSTALLATION
CAUTION: All suspension components that use rub-
ber bushings should be tightened with the vehicle
at the ride height. It is important to have the
springs supporting the weight of the vehicle when
the fasteners are torqued. If the springs are not at
their normal ride position, vehicle ride comfort
could be affected along with premature rubber
bushing wear. Rubber bushings must never be lu-
bricated.
(1) Install the springs and retainer clip. Tighten
the retainer bolts to 21 Nzm (16 ft. lbs.) torque.
(2) Support the axle on a hydraulic jack under the
differential. Position the axle under the vehicle.
(3) Raise the axle with a floor jack and align it
with the spring pads.(4) Position the upper and lower suspension arm at
the axle bracket. Install bolts and nuts finger
tighten.
(5) Connect the track bar to the axle bracket and
install the bolt.Do not tighten at this time.
It is important that the springs support the
weight of the vehicle when the track bar is con-
nected. If the springs are not at their usual po-
sition, the vehicle ride comfort could be affected.
(6) Install the shock absorber and tighten the bolt
to 19 Nzm (14 ft. lbs.) torque.
(7) Install the stabilizer bar link to the axle
bracket. Tighten the nut to 95 Nzm (70 ft. lbs.)
torque.
(8) Install the drag link and tie rod to the steering
knuckles and tighten the nuts to 47 Nzm (35 ft. lbs.)
torque. Install the steering dampener to the axle
bracket and tighten the nut to 75 Nzm (55 ft. lbs.)
torque.
(9) Install the brake components and ABS brake
sensor (if equipped). Refer to Group 5ÐBrakes.
(10) On 4WD vehicles, connect the vent hose to the
tube fitting.
(11) On 4WD vehicles, align the reference marks
and connect the drive shaft to the axle yoke. Tighten
the U-joint clamp bolts to 19 Nzm (14 ft. lbs.) torque.
(12) Check differential lubricant and add if neces-
sary.
(13) Install the wheel and tire assemblies.
(14) Remove the supports and lower the vehicle.
(15) Tighten the upper suspension arm nuts to 75
Nzm (55 ft. lbs.) torque. Tighten the lower suspension
arm nuts to 115 Nzm (85 ft. lbs.) torque.
(16) Tighten the track bar bolt at the axle bracket
to 100 Nzm (74 ft. lbs.) torque.
(17) Check the front wheel alignment.
DRIVE AXLE ASSEMBLY REPLACEMENTÐYJ
VEHICLES
REMOVAL
(1) Raise the vehicle and position support stands
under the frame rails slightly behind the spring
frame brackets.
(2) Remove the front wheels.
(3) Remove the brake components and ABS brake
sensor (if equipped). Refer to Group 5ÐBrakes.
(4) Disconnect the axle vent hose and axle shift
motor vacuum harness.
(5) Mark the drive shaft yoke and axle pinion yoke
for alignment reference. Disconnect the drive shaft
from the axle.
(6) Disconnect the stabilizer bar link at the axle
bracket.
(7) Disconnect the shock absorbers from axle
bracket.
(8) Disconnect the track bar from the axle bracket.
JFRONT SUSPENSION AND AXLE 2 - 21