DESCRIPTION SPECIFICATION
Ring Side Clearance
Compression Rings 0.042 to 0.084 mm
(0.0017 to 0.0033 in.)
Oil Control Rings 0.06 to 0.21 mm
(0.0024 to 0.0083 in.)
Piston Ring Groove
Height
Compression Rings 1.530 to 1.555 mm
(0.0602 to 0.0612 in.)
Oil Control Ring 4.035 to 4.060 mm
(0.1589 to 0.1598 in.)
Piston Ring Groove
Diameter
No.1 Compression Ring 88.39 to 88.65 mm
(3.48 to 3.49 in.)
No.2 Compression Ring 87.63 to 87.88 mm
(3.45 to 3.46 in.)
Oil Control Ring 89.66 to 89.92 mm
(3.53 to 3.54 in.)
Piston Pin Bore Diameter 23.650 to 23.658 mm
(0.9312 to 0.9315 in.)
Piston Pin Diameter 23.637 to 23.640 mm
(0.9306 to 0.9307 in.)
Piston-to-Pin Clearance 0.0102 to 0.0208 mm
(0.0005 to 0.0009 in.)
Piston-to-Pin Connecting
Rod (Press Fit) 8.9 kN (2000 lbf.)
OIL PUMP
Gear-to-Body Clearance 0.051 to 0.102 mm
(Radial) (0.002 to 0.004 in.)
Gear-to-Body Clearance
(Radial) Preferred 0.051 mm (0.002 in.)
Gear End Clearance 0.051 to 0.152 mm
Plastigage (0.002 to 0.006 in.)
Gear End Clearance
Plastigage (Preferred) 0.051 mm (0.002 in.)
Gear End Clearance 0.1016 to 0.2032 mm
Feeler Gauge (0.004 to 0.008 in.)DESCRIPTION SPECIFICATION
Gear End Clearance
Feeler Gauge (Preferred) 0.1778 mm (0.007 in.)
Oil Pressure
At Idle Speed 89.6 kPa (13 psi)
At 1600 rpm & Higher 255 to 517 kPa
(37 to 75 psi)
Oil Pressure Relief 517 kPa (75 psi)
TORQUE - 4.0L ENGINE
DESCRIPTION N´m Ft. In.
Lbs. Lbs.
A/C CompressorÐBolts 28 Ð 250
Block HeaterÐNut 2 Ð 16
Camshaft SprocketÐBolt 68 50 Ð
Camshaft Thrust Plate to
Cylinder BlockÐScrews 24 18 Ð
Clutch Cover to FlywheelÐBolts 54 40 Ð
Coil Bracket to BlockÐBolts 22 Ð 192
Connecting RodÐNuts 45 33 Ð
Cylinder BlockÐDrain Plugs 34 25 Ð
Cylinder HeadÐBolts 135 100 Ð
Cylinder Head CoverÐBolts 10 Ð 85
Distributor ClampÐBolts 23 Ð 204
Engine MountsÐFront
Support Bracket Bolts 61 45 Ð
Support Cushion Bolts/Nuts 41 30 Ð
Support Cushion Bracket Bolts 54 40 Ð
Support Cushion Bracket Stud
Nuts41 30 Ð
Support Cushion Thru-Bolt 65 48 Ð
Engine MountsÐRear
Crossmember to Sill BoltsÐ
(Automatic) 41 30 Ð
Insulator Stud AssemblyÐNut 41 30 Ð
Support Cushion/
CrossmemberÐ
Nuts 22 Ð 192
Support Cushion/BracketÐNuts
(Manual) 75 55 Ð
WJENGINE - 4.0L 9 - 17
ENGINE - 4.0L (Continued)
All Jeep engines are equipped with a high quality
full-flow, throw-away type oil filter. DaimlerChrysler
Corporation recommends a Mopartor equivalent oil
filter be used.
(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 or filter
adapter housing (Fig. 75).
(4) When filter separates from adapter nipple, tip
gasket end upward to minimize oil spill. Remove fil-
ter from vehicle.
(5) Make sure old gasket comes off with oil filter.
With a wiping cloth, clean the gasket sealing surface
(Fig. 76) of oil and grime.
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. 76) hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
OIL PAN
DESCRIPTION
The oil pan is made of stamped steel. The oil pan
gasket is a one piece steel backbone silicone coated
gasket (Fig. 77).
REMOVAL
(1) Disconnect negative cable from battery.
(2) Raise the vehicle.
(3) Remove the oil pan drain plug and drain the
engine oil.
(4) Disconnect the exhaust pipe at the exhaust
manifold.
(5) Disconnect the exhaust hanger at the catalytic
converter and lower the pipe.
(6) Remove the starter motor. (Refer to 8 - ELEC-
TRICAL/STARTING/STARTER MOTOR - REMOV-
AL).
(7) Remove the engine flywheel and transmission
torque converter housing access cover.
(8) If equipped with an oil level sensor, disconnect
the sensor.
(9) Position a jack stand directly under the engine
vibration damper.
Fig. 75 Oil FilterÐ4.0L Engine
1 - CYLINDER BLOCK
2 - ADAPTER
3 - OIL FILTER
Fig. 76 Oil Filter Sealing SurfaceÐTypical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTER
Fig. 77 Oil Pan
1 - OIL PAN
2 - OIL PAN DRAIN PLUG
9 - 54 ENGINE - 4.0LWJ
OIL FILTER (Continued)
(9) Lower the engine until it is properly located on
the engine mounts.
(10) Install the through bolts and tighten the nuts.
(11) Lower the jack stand and remove the piece of
wood.
(12) Install the engine flywheel and transmission
torque converter housing access cover.
(13) Install the engine starter motor. (Refer to 8 -
ELECTRICAL/STARTING/STARTER MOTOR -
INSTALLATION).
(14) Connect the exhaust pipe to the hanger and to
the engine exhaust manifold.
(15) Install transmission oil cooling lines (if
equipped) and oxygen sensor wiring supports that
attach to the oil pan studs.
(16) Install the oil pan drain plug (Fig. 81).
Tighten the plug to 34 N´m (25 ft. lbs.) torque.
(17) Lower the vehicle.
(18) Connect negative cable to battery.
(19) Fill the oil pan with engine oil to the specified
level.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR FAN. DO
NOT WEAR LOOSE CLOTHING.
(20) Start the engine and inspect for leaks.
ENGINE OIL PRESSURE
SENSOR
DESCRIPTION
The 3±wire, solid-state engine oil pressure sensor
(sending unit) is located in an engine oil pressure
gallery.
OPERATION
The oil pressure sensor uses three circuits. They
are:
²A 5±volt power supply from the Powertrain Con-
trol Module (PCM)
²A sensor ground through the PCM's sensor
return
²A signal to the PCM relating to engine oil pres-
sure
The oil pressure sensor has a 3±wire electrical
function very much like the Manifold Absolute Pres-
sure (MAP) sensor. Meaning different pressures
relate to different output voltages.
A 5±volt supply is sent to the sensor from the PCM
to power up the sensor. The sensor returns a voltage
signal back to the PCM relating to engine oil pres-
sure. This signal is then transferred (bussed) to theinstrument panel on either a CCD or PCI bus circuit
(depending on vehicle line) to operate the oil pressure
gauge and the check gauges lamp. Ground for the
sensor is provided by the PCM through a low-noise
sensor return.
OIL PUMP
REMOVAL
A gear-type oil pump is mounted at the underside
of the cylinder block opposite the No.4 main bearing.
(1) Drain the engine oil.
(2) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(3) Remove the pump-to-cylinder block attaching
bolts. Remove the pump assembly with gasket (Fig.
82).
CAUTION: If the oil pump is not to be serviced, DO
NOT disturb position of oil inlet tube and strainer
assembly in pump body. If the tube is moved within
the pump body, a replacement tube and strainer
assembly must be installed to assure an airtight
seal.
Fig. 82 Oil Pump Assembly
1 - OIL FILTER ADAPTOR
2 - BLOCK
3 - GASKET
4 - OIL INLET TUBE
5 - OIL PUMP
6 - STRAINER ASSEMBLY
7 - ATTACHING BOLTS
9 - 56 ENGINE - 4.0LWJ
OIL PAN (Continued)
CONDITION POSSIBLE CAUSES CORRECTIONS
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
SPECIFICATIONS).
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - LUBRICATION
CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS 1. Gaskets and O-Rings. 1.
(a) Misaligned or damaged. (a) Replace as necessary.
(b) Loose fasteners, broken or
porous metal parts.(b) Tighten fasteners, Repair or
replace metal parts.
2. Crankshaft rear seal 2. Replace as necessary (Refer to 9 -
ENGINE/ENGINE BLOCK/
CRANKSHAFT OIL SEAL - REAR -
REMOVAL).
3. Crankshaft seal flange.
Scratched, nicked or grooved.3. Polish or replace crankshaft.
4. Oil pan flange cracked. 4. Replace oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN -
REMOVAL).
5. Timing chain cover seal, damaged
or misaligned.5. Replace seal (Refer to 9 -
ENGINE/ENGINE BLOCK/
CRANKSHAFT OIL SEAL - FRONT -
REMOVAL).
6. Scratched or damaged vibration
damper hub.6. Polish or replace damper.
WJENGINE - 4.7L 9 - 67
ENGINE - 4.7L (Continued)
(19) Remove the retaining bolt and the camshaft
drive gear.
CAUTION: Do not allow the engine to rotate. severe
damage to the valve train can occur.
CAUTION: Do not overlook the four smaller bolts at
the front of the cylinder head. Do not attempt to
remove the cylinder head without removing these
four bolts.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel for any reason. A damaged target wheel
can result in a vehicle no start condition.
NOTE: The cylinder head is attached to the cylinder
block with fourteen bolts.
(20) Remove the cylinder head retaining bolts.
(21) Remove the cylinder head and gasket. Discard
the gasket.
CAUTION: Do not lay the cylinder head on its gas-
ket sealing surface, do to the design of the cylinder
head gasket any distortion to the cylinder head
sealing surface may prevent the gasket from prop-
erly sealing resulting in leaks.
CLEANING
To ensure engine gasket sealing, proper surface
preparation must be performed, especially with the
use of aluminum engine components. (Refer to 9 -
ENGINE - STANDARD PROCEDURE)
INSPECTION
(1) Inspect the cylinder head for out-of-flatness,
using a straightedge and a feeler gauge. If tolerances
exceed 0.0508 mm (0.002 in.) replace the cylinder
head.
(2) Inspect the valve seats for damage. Service the
valve seats as necessary.
(3) Inspect the valve guides for wear, cracks or
looseness. If either condition exist, replace the cylin-
der head.
INSTALLATION
NOTE: The cylinder head bolts are tightened using
a torque plus angle procedure. The bolts must be
examined BEFORE reuse. If the threads are necked
down the bolts should be replaced.
Necking can be checked by holding a straight edge
against the threads. If all the threads do not contact
the scale, the bolt should be replaced (Fig. 13).
CAUTION: When cleaning cylinder head and cylin-
der block surfaces, DO NOT use a metal scraper
because the surfaces could be cut or ground. Use
only a wooden or plastic scraper.
(1) Clean the cylinder head and cylinder block
mating surfaces (Refer to 9 - ENGINE - STANDARD
PROCEDURE).
(2) Position the new cylinder head gasket on the
locating dowels.
CAUTION: When installing cylinder head, use care
not damage the tensioner arm or the guide arm.
(3) Position the cylinder head onto the cylinder
block. Make sure the cylinder head seats fully over
the locating dowels.
NOTE: The four smaller cylinder head mounting
bolts require sealant to be added to them before
installing. Failure to do so may cause leaks.
(4) Lubricate the cylinder head bolt threads with
clean engine oil and install the ten M10 bolts.
(5) Coat the four M8 cylinder head bolts with
Mopar Lock and Seal Adhesivethen install the
bolts.
NOTE: The cylinder head bolts are tightened using
an angle torque procedure, however, the bolts are
not a torque-to-yield design.
(6) Tighten the bolts in sequence (Fig. 30) using
the following steps and torque values:
²Step 1: Tighten bolts 1±10, 27 N´m (20 ft. lbs.).
Fig. 29 Cylinder Head Access Plugs
1 - RIGHT CYLINDER HEAD ACCESS PLUG
2 - LEFT CYLINDER HEAD ACCESS PLUG
WJENGINE - 4.7L 9 - 99
CYLINDER HEAD - RIGHT (Continued)
(1) Lubricate upper main bearing halves with
clean engine oil.
CAUTION: When installing crankshaft, use care not
to damage bearing surfaces on the crankshaft.
NOTE: Apply sealant to the target wheel retaining
screws prior to installation.
(2) Install the crankshaft target wheel. Torque the
mounting screws to 22 N´m (21 ft. lbs.).
(3) Position crankshaft in cylinder block.
(4) Install the thrust washers (Fig. 55).
CAUTION: The bedplate to cylinder block mateing
surface must be coated with sealant prior to instal-
lation. Failure to do so will cause severe oil leaks.
NOTE: The installation time to install the bedplate
after the sealant has been applied is critical.
NOTE: Make sure that the bedplate and cylinder
block sealing surfaces are clean and free of oil or
other contaminants. Contaminants on the sealing
surfaces may cause main bearing distortion and/or
oil leaks.
(5) Apply a 2.5mm (0.100 inch) (Fig. 56) bead of
MopartGen II Silicone Rubber Adhesive sealant to
the cylinder block-to-bedplate mating surface as
shown (Fig. 57).(6) Coat the crankshaft main bearing journals
with clean engine oil and position the bedplate onto
the cylinder block.
NOTE: Lubricate the bedplate retaining bolts with
clean engine oil prior to installation.
(7) Install the bedplate retaining bolts, making
sure to place the stud bolts in the correct location,
Torque the bolts in the sequence shown (Fig. 58).
²Tighten boltsA± Lto 54 N´m (40 ft. lbs.)
²Tighten bolts1±10to 2.8 N´m (25 in. lbs.)
²Turn bolts1±10an additional 90É.
Fig. 55 Crankshaft Thrust Washer Installation
1 - CRANKSHAFT THRUST WASHER
Fig. 56 Cutting Aplicator to Achieve 2.5mm (0.100
in.) Bead
1 - CUT HERE
Fig. 57 Cylinder Block-to-Bedplate Sealent Bead
Location
1 - CYLINDER BLOCK
2 - SEALANT BEAD LOCATION
WJENGINE - 4.7L 9 - 113
CRANKSHAFT (Continued)
FRAME & BUMPERS
TABLE OF CONTENTS
page page
FRONT ABSORBER
REMOVAL.............................1
INSTALLATION..........................1
FRONT FASCIA
REMOVAL.............................1
INSTALLATION..........................1
REAR ABSORBER
REMOVAL.............................2
INSTALLATION..........................2
REAR FASCIA
REMOVAL.............................2
INSTALLATION..........................4
FRAME
SPECIFICATIONS
SPECIFICATIONS - TORQUE.............4
FRAME DIMENSIONS...................4
FRONT SKID PLATE
REMOVAL.............................7INSTALLATION..........................7
FRONT TOW HOOK
REMOVAL.............................7
INSTALLATION..........................7
FUEL TANK SKID PLATE
DESCRIPTION..........................7
REAR TOW HOOK
REMOVAL.............................7
INSTALLATION..........................7
TRAILER HITCH
REMOVAL.............................8
INSTALLATION..........................8
TRANSFER CASE SKID PLATE
REMOVAL.............................8
INSTALLATION..........................8
FRONT ABSORBER
REMOVAL
(1) Remove front fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/FRONT FASCIA
- REMOVAL).
(2) Remove the retainer attaching the absorber to
the fascia.
(3) Separate the absorber from the fascia.
INSTALLATION
(1) Position the absorber on the fascia.
(2) Install the retainer attaching the absorber to
the fascia.
(3) Install front fascia. Refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/FRONT FASCIA
- INSTALLATION).
FRONT FASCIA
REMOVAL
(1) Raise and support vehicle.
(2) Turn front wheels to access rivets and remove
plastic rivets attaching fascia to wheel liner.
(3) Remove bolts attaching fascia to fender (Fig. 1).(4) Remove plastic push pin fasteners attaching
front fascia to lower radiator crossmember splash
shield (Fig. 2).
(5) Disengage fog lamp connectors, if equipped.
(6) Remove screws attaching fascia/grille to upper
radiator crossmember (Fig. 3).
(7) Slide fascia forward to separate from vehicle.
INSTALLATION
(1) Slide fascia onto vehicle engaging fascia with
tabs on bottom of front fenders.
(2) Install screws attaching fascia/grille to upper
radiator crossmember (Fig. 3).
(3) Install bolts attaching fascia to fender (Fig. 1).
(4) Engage fog lamp connectors, if equipped.
(5) Install plastic rivets attaching fascia to wheel
liner.
(6) Install plastic push pin fasteners attaching
front fascia to lower radiator crossmember splash
shield (Fig. 2).
(7) Remove supports and lower vehicle.
WJFRAME & BUMPERS 13 - 1
INSTALLATION
(1) Position fascia on vehicle aligning retainers
with slots in quarter panel (Fig. 7).
(2) Press forward edges of fascia inward to engage
retainers.
(3) Install screws attaching fascia to liftgate open-
ing.
(4) Install plastic push pins attaching fascia to lift-
gate opening.
(5) Install nuts attaching upper edge of fascia to
quarter panel and wheel liner.
(6) Install plastic rivets attaching fascia to wheel
liner.
(7) Install support lower vehicle.
(8) Install plastic push pins attaching fascia to fuel
tank skid plate.
(9) Install the interior trim panels removed to
access fascia retainers.
(10) Install tie down loop screws.
(11) Install the wheels, refer to section 22 for
tightening sequence and torque specifications.
FRAME
SPECIFICATIONS
SPECIFICATIONS - TORQUE
TORQUE SPECIFICATIONS
DESCRIPTION N´mFt.
Lbs.In.
Lbs.
Front Tow Hook Bolt 54 40 Ð
Front Skid Plate Bolt 54 40 Ð
Rear Tow Hook Bolt 68 50 Ð
Trailer Hitch Bolts 68 50 Ð
Transfer Case Skid Plate
Bolts34 25 Ð
FRAME DIMENSIONS
INDEX
DESCRIPTION FIGURE
SIDE VIEW 8
BOTTOM VIEW 9
Fig. 6 Rear Fascia Retainers
1 - RETAINER
2 - FASCIA
Fig. 7 Fascia Attachment
1 - SLOT
2 - QUARTER PANEL
13 - 4 FRAME & BUMPERSWJ
REAR FASCIA (Continued)