
²Cylinder head covers (Refer to 9 - ENGINE/
CYLINDER HEAD/CYLINDER HEAD COVER(S) -
INSTALLATION).
²Oil pan and gasket/windage tray. (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
(11) Fill crankcase with proper engine oil to cor-
rect level.
(12) Connect negative cable to battery.
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING
Before reinstalling used rings or installing new
rings, the ring clearances must be checked.
(1) Wipe the cylinder bore clean.
(2) Insert the ring in the cylinder bore.
NOTE: The ring gap measurement must be made
with the ring positioned at least 12mm (0.50 inch.)
from bottom of cylinder bore.
(3) Using a piston, to ensure that the ring is
squared in the cylinder bore, slide the ring downward
into the cylinder.
(4) Using a feeler gauge check the ring end gap
(Fig. 74). Replace any rings not within specification.
PISTON RING SIDE CLEARANCE
NOTE: Make sure the piston ring grooves are clean
and free of nicks and burrs.
(5) Measure the ring side clearance as shown (Fig.
75)make sure the feeler gauge fits snugly between
the ring land and the ring. Replace any ring not
within specification.(6) Rotate the ring around the piston, the ring
must rotate in the groove with out binding.
PISTON RING SPECIFICATION CHART
Ring Position Groove Maximum
Clearance Clearance
Upper Ring .051-.094mm 0.11mm
(0.0020- .0037
in.)(0.004 in.)
Intermediate
Ring0.04-0.08mm 0.10mm
(0.0016-0.0031
in.)(0.004 in.)
Oil Control Ring .019-.229mm .25mm
(Steel Rails) (.0007-.0090 in.) (0.010 in.)
Ring Position Ring Gap Wear Limit
Upper Ring 0.23-0.39mm 0.43mm
(0.009-0.015 in.) (0.0017 in.)
Intermediate
Ring0.40-0.66mm 0.74mm
(0.015-0.026 in.) (0.029 in.)
Oil Control Ring 0.028-0.79mm 1.55mm
(Steel Rail) (0.011- 0.031
in.)(0.061 in.)
Fig. 74 Ring End Gap Measurement - Typical
1 - FEELER GAUGE
Fig. 75 Measuring Piston Ring Side Clearance
1 - FEELER GAUGE
WJENGINE - 4.7L 9 - 121
PISTON & CONNECTING ROD (Continued)

(7) The No. 1 and No. 2 piston rings have a differ-
ent cross section. Ensure No. 2 ring is installed with
manufacturers I.D. mark (Dot) facing up, towards top
of the piston.
NOTE: Piston rings are installed in the following
order:
²Oil ring expander.
²Upper oil ring side rail.
²Lower oil ring side rail.
²No. 2 Intermediate piston ring.
²No. 1 Upper piston ring.
(8) Install the oil ring expander.
(9) Install upper side rail (Fig. 76) by placing one
end between the piston ring groove and the expander
ring. Hold end firmly and press down the portion to
be installed until side rail is in position. Repeat this
step for the lower side rail.
(10) Install No. 2 intermediate piston ring using a
piston ring installer (Fig. 77).
(11) Install No. 1 upper piston ring using a piston
ring installer (Fig. 77).
(12) Position piston ring end gaps as shown in
(Fig. 78). It is important that expander ring gap is at
least 45É from the side rail gaps, but not on the pis-
ton pin center or on the thrust direction.
VIBRATION DAMPER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
NOTE: Transmission cooler line snaps into shroud
lower right hand corner.
Fig. 76 Side RailÐInstallation
1 - SIDE RAIL END
Fig. 77 Upper and Intermediate RingsÐInstallation
Fig. 78 Piston Ring End Gap Position
1 - SIDE RAIL UPPER
2 - NO. 1 RING GAP
3 - PISTON PIN
4 - SIDE RAIL LOWER
5 - NO. 2 RING GAP AND SPACER EXPANDER GAP
9 - 122 ENGINE - 4.7LWJ
PISTON RINGS (Continued)

(6) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(7) Disconnect generator electrical connections.
(8) Unbolt the generator and move it away from
the intake manifold for clearance.
(9) Disconnect air conditioning compressor electri-
cal connections.
(10) Unbolt the air conditioning compressor and
move it away from the intake manifold for clearance.
(11) Disconnect left and right radio suppressor
straps.
(12) Disconnect and remove ignition coil towers
(Refer to 8 - ELECTRICAL/IGNITION CONTROL/
IGNITION COIL - REMOVAL).
(13) Remove top oil dipstick tube retaining bolt
and ground strap.
(14) Bleed pressure from fuel system (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY - STANDARD
PROCEDURE).
(15) Remove fuel rail (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL RAIL - REMOVAL).
(16) Remove throttle body assembly and mounting
bracket.
(17) Drain cooling system below coolant tempera-
ture level (Refer to 7 - COOLING - STANDARD
PROCEDURE).
(18) Remove coolant temperature sensor (Refer to
7 - COOLING/ENGINE/ENGINE COOLANT TEMP
SENSOR - REMOVAL).
(19) Remove cowl to hood seal. (Refer to 23 -
BODY/WEATHERSTRIP/SEALS/COWL WEATHER-
STRIP - REMOVAL).
(20) Remove right side engine lifting stud.
(21) Remove intake manifold retaining fasteners,
in reverse order of tightening sequence (Fig. 105).
NOTE: Intake must be lifted upward and level in the
front and rear to clear the cowl. Interference with
the cowl will occur during removal.
(22) Remove intake manifold.
CLEANING
NOTE: There is NO approved repair procedure for
the intake manifold. If severe damage is found dur-
ing inspection, the intake manifold must be
replaced.
Before installing the intake manifold thoroughly
clean the mating surfaces. Use a suitable cleaning
solvent, then air dry.
INSPECTION
(1) Inspect the intake sealing surface for cracks,
nicks and distortion.(2) Inspect the intake manifold vacuum hose fit-
tings for looseness or blockage.
(3) Inspect the manifold to throttle body mating
surface for cracks, nicks and distortion.
INSTALLATION
(1) Install intake manifold gaskets.
(2) Install intake manifold.
(3) Install intake manifold retaining bolts and
tighten in sequence shown in (Fig. 106) to 12 N´m
(105 in. lbs.).
(4) Install left and right radio suppressor straps.
(5) Install throttle body assembly.
(6) Install throttle cable bracket.
Fig. 105 Intake Manifold Tightening Sequence
Fig. 106 Intake Manifold Tightening Sequence
WJENGINE - 4.7L 9 - 137
INTAKE MANIFOLD (Continued)

(7) Connect throttle cable and speed control cable
to throttle body.
(8) Install fuel rail (Refer to 14 - FUEL SYSTEM/
FUEL DELIVERY/FUEL RAIL - INSTALLATION).
(9) Install ignition coil towers (Refer to 8 - ELEC-
TRICAL/IGNITION CONTROL/IGNITION COIL -
INSTALLATION).
(10) Install coolant temperature sensor (Refer to 7
- COOLING/ENGINE/ENGINE COOLANT TEMP
SENSOR - INSTALLATION).
(11) Connect electrical connectors for the following
components:
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
²Ignition coil towers
²Fuel injectors
(12) Install top oil dipstick tube retaining bolt and
ground strap.
(13) Install right side engine lifting stud.
(14) Install generator including electrical connec-
tions (Refer to 8 - ELECTRICAL/CHARGING/GEN-
ERATOR - INSTALLATION).
(15) Connect Vapor purge hose, Brake booster
hose, Speed control servo hose, Positive crankcase
ventilation (PCV) hose.
(16) Install air conditioning compressor including
electrical connections.
(17) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(18) Install accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(19) Install cowl to hood seal (Refer to 23 - BODY/
WEATHERSTRIP/SEALS/COWL WEATHERSTRIP -
INSTALLATION).
(20) Install air cleaner housing and throttle body
resonator. Tighten resonator bolts 4.5 N´m (40 in.
lbs.).
(21) Connect negative cable to battery.
EXHAUST MANIFOLD - LEFT
DESCRIPTION
The exhaust manifolds are log style with a pat-
ented flow enhancing design to maximize perfor-
mance. The exhaust manifolds are made of high
silicon molybdenum cast iron. A perforated core
graphite exhaust manifold gasket is used to improve
sealing to the cylinder head. The exhaust manifolds
are covered by a three layer laminated heat shield
for thermal protection and noise reduction. The heat
shields are fastened with a torque prevailing nutthat is backed off slightly to allow for the thermal
expansion of the exhaust manifold.
REMOVAL
(1) Disconnect negative cable for battery.
(2) Hoist vehicle.
(3) Disconnect exhaust pipe at manifold.
(4) Lower vehicle.
(5) Remove air cleaner housing and tube.
(6) Remove the front two exhaust heat shield
retaining fasteners. Raise vehicle and remove the
fasteners at rear of heat shield.
(7) Remove heat shield (Fig. 107).
(8) Lower vehicle and remove the upper exhaust
manifold retaining bolts (Fig. 107).
(9) Raise vehicle and remove the lower exhaust
manifold retaining bolts (Fig. 107).
(10) Remove exhaust manifold and gasket (Fig.
107). Manifold is removed from below the engine
compartment.
CLEANING
(1) Clean the exhaust manifold using a suitable
cleaning solvent, then allow to air dry.
(2) Clean all gasket residue from the manifold
mating surface.
INSPECTION
(1) Inspect the exhaust manifold for cracks in the
mating surface and at every mounting bolt hole.
(2) Using a straight edge and a feeler gauge, check
the mating surface for warp and twist.
(3) Inspect the manifold to exhaust pipe mating
surface for cracks, gouges, or other damage that
would prevent sealing.
INSTALLATION
(1) Install exhaust manifold and gasket from below
engine compartment.
(2) Install lower exhaust manifold fasteners (Fig.
107). DO NOT tighten until all fasteners are in
place.
(3) Lower vehicle and install upper exhaust mani-
fold fasteners (Fig. 107). Tighten all manifold bolts
starting at center and working outward to 25 N´m
(18 ft. lbs.).
CAUTION: Over tightening heat shield fasteners,
may cause shield to distort and/or crack.
(4) Install exhaust manifold heat shield (Fig. 107).
Tighten fasteners to 8 N´m (72 in. lbs.), then loosen
45 degrees.
(5) Install air cleaner housing and tube.
(6) Connect exhaust pipe to manifold.
(7) Connect negative cable to battery.
9 - 138 ENGINE - 4.7LWJ
INTAKE MANIFOLD (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)

TRAILER HITCH
REMOVAL
(1) Remove rear fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/REAR FASCIA -
REMOVAL).
(2) Remove screws attaching trailer harness plug
to trailer hitch.
(3) Disconnect harness connector from harness
plug.
(4) Position support stands under trailer hitch.
(5) Remove bolts attaching trailer hitch to frame
rails (Fig. 13).
(6) Separate trailer hitch from vehicle.
INSTALLATION
(1) Position trailer hitch on support stands.
(2) Position trailer hitch on vehicle.
(3) Install bolts attaching trailer hitch to frame
rails. Tighten bolts to 68 N´m (50 lbs.) torque.(4) Connect harness connector to harness plug.
(5) Position harness plug in trailer hitch and
install screws.
(6) Install rear fascia, refer to (Refer to 13 -
FRAMES & BUMPERS/BUMPERS/REAR FASCIA -
INSTALLATION).
TRANSFER CASE SKID PLATE
REMOVAL
(1) Support skid plate.
(2) Remove bolts that attach skid plate to trans-
mission support crossmember and frame sill (Fig.
14).
(3) Remove support and skid plate from vehicle.
INSTALLATION
(1) Install nutserts, if removed.
(2) Position and support skid plate at the frame
sill and transmission support crossmember.
(3) Attach skid plate to frame sill and crossmem-
ber with the bolts. Tighten bolts to 34 N´m (25 ft. lbs)
torque.
Fig. 13 Trailer Hitch
1 - FUEL TANK
2 - TRAILER HITCH
Fig. 14 Transfer Case Skid Plate
1 - TRANSFER CASE
2 - NUTSERT
3 - SKID PLATE
4 - CROSSMEMBER
13 - 8 FRAME & BUMPERSWJ

FUEL SYSTEM
TABLE OF CONTENTS
page page
FUEL DELIVERY..........................1FUEL INJECTION........................31
FUEL DELIVERY
TABLE OF CONTENTS
page page
FUEL DELIVERY
DESCRIPTION..........................2
OPERATION............................2
DIAGNOSIS AND TESTING
FUEL PRESSURE LEAK DOWN TEST......2
STANDARD PROCEDURE - FUEL SYSTEM
PRESSURE RELEASE...................4
SPECIFICATIONS
FUEL SYSTEM PRESSURE..............4
TORQUE - FUEL DELIVERY..............4
SPECIAL TOOLS
FUEL SYSTEM........................5
FUEL FILTER/PRESSURE REGULATOR
DESCRIPTION..........................5
OPERATION............................5
REMOVAL.............................6
INSTALLATION..........................6
FUEL LEVEL SENDING UNIT / SENSOR
DESCRIPTION..........................7
OPERATION............................7
DIAGNOSIS AND TESTING - FUEL LEVEL
SENDING UNIT........................7
REMOVAL.............................7
INSTALLATION..........................8
FUEL LINES
DESCRIPTION..........................8
FUEL PUMP
DESCRIPTION..........................8
OPERATION............................9
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - FUEL PUMP
CAPACITY TEST.......................9
DIAGNOSIS AND TESTING - FUEL PUMP
AMPERAGE TEST......................9FUEL PUMP PRESSURE TEST...........11
FUEL PUMP MODULE
DESCRIPTION.........................13
OPERATION...........................13
REMOVAL.............................13
INSTALLATION.........................14
FUEL RAIL
DESCRIPTION
DESCRIPTION - 4.7L...................15
DESCRIPTION - 4.0L...................15
OPERATION
OPERATION - 4.7L....................15
OPERATION - 4.0L....................15
REMOVAL
REMOVAL - 4.7L......................15
REMOVAL - 4.0L......................17
INSTALLATION
INSTALLATION - 4.7L..................18
INSTALLATION - 4.0L..................18
FUEL TANK
DESCRIPTION.........................19
OPERATION...........................19
REMOVAL.............................19
INSTALLATION.........................20
INLET FILTER
REMOVAL.............................27
INSTALLATION.........................27
QUICK CONNECT FITTING
DESCRIPTION.........................27
STANDARD PROCEDURE - QUICK-CONNECT
FITTINGS...........................27
WJFUEL SYSTEM 14 - 1