2002 JEEP GRAND CHEROKEE Oil pan

DESCRIPTION N´m Ft. In.
Lbs. Lbs.
Exhaust Manifold Heat
ShieldÐNuts8Ð72
Then loosen 45É
FlexplateÐBolts 60 45 Ð
Engine Mount Bracket to
BlockÐBolts61 45 Ð
Rear Mount to
TransmissionÐBolts46 34 Ð
Generator MountingÐBolts
M10 Bolts 54 40 Ð
M8 Bolts 28 Ð 250
Intake ManifoldÐBolts 12 Ð 105
Refer to Procedure
for
Tightening Sequence
Oil PanÐBolts 15 Ð 130
Oil PanÐDrain Plug 34 25 Ð
Oil PumpÐBolts 28 Ð 250
Oil Pump CoverÐBolts 12 Ð 105
Oil Pickup TubeÐBolt and
Nut28 Ð 250
Oil Dipstick Tube to Engine
BlockÐBolt 15 Ð 130
Oil Fill TubeÐBolts 12 Ð 105
Timing Chain GuideÐBolts 28 Ð 250
Timing Chain Tensioner
ArmÐSpecial
Pin Bolt 17 Ð 150
Hydraulic TensionerÐBolts 28 Ð 250
Timing Chain Primary
TensionerÐBolts28 Ð 250
Timing Drive Idler SprocketÐ
Bolt34 25 Ð
Thermostat HousingÐBolts 13 Ð 115
Water PumpÐBolts 54 40 ÐSPECIAL TOOLS
4.7L ENGINE
Spanner Wrench 6958
Adapter Pins 8346
Engine Lifting Studs 8400
Engine Lift Fixture 8347
9 - 80 ENGINE - 4.7LWJ
ENGINE - 4.7L (Continued)

NOTE: When gripping the camshaft, place the pliers
on the tube portion of the camshaft only. Do not
grip the lobes or the sprocket areas.
(7) Using the adjustable pliers, rotate the cam-
shaft until the camshaft sprocket dowel is aligned
with the slot in the camshaft sprocket. Install the
sprocket onto the camshaft (Fig. 19).
CAUTION: Remove excess oil from camshaft
sprocket bolt. Failure to do so can cause bolt over-
torque resulting in bolt failure.
(8) Remove excess oil from bolt, then install the
camshaft sprocket retaining bolt and hand tighten.
(9) Remove Special Tool 8350 timing chain wedge
(Fig. 20).
(10) Using Special Tool 6958 spanner wrench with
adapter pins 8346 (Fig. 21), torque the camshaft
sprocket retaining bolt to 122 N´m (90 ft. lbs.).
(11) Install the cylinder head cover.
Fig. 18 Timing Chain to Sprocket Alignment
1 - LEFT CYLINDER HEAD
2 - RIGHT CYLINDER HEAD
Fig. 19 Camshaft Sprocket Installation
1 - ADJUSTABLE PLIERS
2 - CAMSHAFT DOWEL
WJENGINE - 4.7L 9 - 91
CAMSHAFT(S) - LEFT (Continued)

INSTALLATION
(1) Lubricate camshaft journals with clean engine
oil.
NOTE: Position the right side camshaft so that the
camshaft sprocket dowel is near the 10 o'clock
position, This will place the camshaft at the neutral
position easing the installation of the camshaft
bearing caps.
(2) Position the camshaft into the cylinder head.
(3) Install the camshaft bearing caps, hand tighten
the retaining bolts.
(4) Working in 1/2 turn increments, tighten the
bearing cap retaining bolts starting with the middle
cap working outward (Fig. 34).
(5) Torque the camshaft bearing cap retaining
bolts to 11 N´m (100 in. lbs.).
(6) Position the camshaft drive gear into the tim-
ing chain aligning the V8 mark between the two
marked chain links (Two links marked during
removal) (Fig. 35).NOTE: When gripping the camshaft, place the pliers
on the tube portion of the camshaft only. Do not
grip the lobes or the sprocket areas.
(7) Using the adjustable pliers, rotate the cam-
shaft until the camshaft sprocket dowel is aligned
with the slot in the camshaft sprocket. Install the
sprocket onto the camshaft (Fig. 36).
CAUTION: Remove excess oil from camshaft
sprocket bolt. Failure to do so can cause bolt over-
torque resulting in bolt failure.
(8) Remove excess oil from camshaft sprocket bolt,
then install the camshaft sprocket retaining bolt and
hand tighten.
(9) Remove timing chain wedge special tool 8350
(Fig. 31).
(10) Using Special Tool 6958 spanner wrench with
adapter pins 8346 (Fig. 37), torque the camshaft
sprocket retaining bolt to 122 N´m (90 ft. lbs.).
(11) Install the camshaft position sensor (Fig. 32).
(12) Install the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
Fig. 33 Camshaft Sprocket and Chain
1 - ADJUSTABLE PLIERS
2 - SPROCKET BOLT
3 - CAMSHAFT SPROCKET AND CHAIN
4 - CAMSHAFTFig. 34 Camshaft Bearing Caps Tightening
Sequence
9 - 102 ENGINE - 4.7LWJ
CAMSHAFT(S) - RIGHT (Continued)

free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
CLEANING
Thoroughly clean the oil pan and engine block gas-
ket surfaces.
Use compressed air to clean out:
²The galley at the oil filter adaptor hole.
²The front and rear oil galley holes.
²The feed holes for the crankshaft main bearings.
Once the block has been completely cleaned, apply
Loctite PST pipe sealant with Teflon 592 to the
threads of the front and rear oil galley plugs. Tighten
the plugs to 34 N´m (25 ft. lbs.) torque.
INSPECTION
(1) It is mandatory to use a dial bore gauge to
measure each cylinder bore diameter. To correctly
select the proper size piston, a cylinder bore gauge,
capable of reading in 0.003 mm (.0001 in.) INCRE-
MENTS is required. If a bore gauge is not available,
do not use an inside micrometer (Fig. 46).
(2) Measure the inside diameter of the cylinder
bore at three levels below top of bore. Start perpen-
dicular (across or at 90 degrees) to the axis of the
crankshaft and then take two additional reading.(3) Measure the cylinder bore diameter crosswise
to the cylinder block near the top of the bore. Repeat
the measurement near the middle of the bore, then
repeat the measurement near the bottom of the bore.
(4) Determine taper by subtracting the smaller
diameter from the larger diameter.
(5) Rotate measuring device 90É and repeat steps
above.
(6) Determine out-of-roundness by comparing the
difference between each measurement.
(7) If cylinder bore taper does not exceed 0.025
mm (0.001 inch) and out-of-roundness does not
exceed 0.025 mm (0.001 inch), the cylinder bore can
be honed. If the cylinder bore taper or out- of-round
condition exceeds these maximum limits, the cylinder
block must be replaced. A slight amount of taper
always exists in the cylinder bore after the engine
has been in use for a period of time.
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING ROD
BEARING FITTING
Inspect the connecting rod bearings for scoring and
bent alignment tabs (Fig. 47) (Fig. 48). Check the
bearings for normal wear patterns, scoring, grooving,
fatigue and pitting (Fig. 49). Replace any bearing
that shows abnormal wear.
Inspect the connecting rod journals for signs of
scoring, nicks and burrs.
Misaligned or bent connecting rods can cause
abnormal wear on pistons, piston rings, cylinder
walls, connecting rod bearings and crankshaft con-
necting rod journals. If wear patterns or damage to
any of these components indicate the probability of a
misaligned connecting rod, inspect it for correct rod
alignment. Replace misaligned, bent or twisted con-
necting rods.
(1) Wipe the oil from the connecting rod journal.
(2) Lubricate the upper bearing insert and install
in connecting rod.
(3) Use piston ring compressor and Guide Pins
Special Tool 8507 (Fig. 50) to install the rod and pis-
ton assemblies. The oil slinger slots in the rods must
face front of the engine. The ªFº's near the piston
wrist pin bore should point to the front of the engine.
(4) Install the lower bearing insert in the bearing
cap. The lower insert must be dry. Place strip of Plas-
tigage across full width of the lower insert at the cen-
ter of bearing cap. Plastigage must not crumble in
use. If brittle, obtain fresh stock.
(5) Install bearing cap and connecting rod on the
journal and tighten bolts to 27 N´m (20 ft. lbs.) plus a
90É turn. DO NOT rotate crankshaft. Plastigage will
smear, resulting in inaccurate indication.
Fig. 46 Bore GaugeÐTypical
1 - FRONT
2 - BORE GAUGE
3 - CYLINDER BORE
4-38MM
(1.5 in)
WJENGINE - 4.7L 9 - 109
ENGINE BLOCK (Continued)

REMOVAL
NOTE: To remove the crankshaft from the engine,
the engine must be removed from the vehicle.
(1) Remove the engine. (Refer to 9 - ENGINE -
REMOVAL).
(2) Remove the engine oil pump.(Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP - REMOVAL).
CAUTION: DO NOT pry on the oil pan gasket when
removing the oil pan, The oil pan gasket is mounted
to the cylinder block in three locations and will
remain attached to block when removing oil pan.
Gasket can not be removed with oil pan.
(3) Remove oil pan. (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PAN - REMOVAL).
(4) Remove the oil pump pickup tube and oil pan
gasket /windage tray.
(5) Remove the bedplate mounting bolts. Note the
location of the three stud bolts for installation.
(6) Remove the connecting rods from the crank-
shaft.
CAUTION: The bedplate to cylinder block mating
surface is a critical sealing surface. Do not pry on
or damage this surface in anyway.
NOTE: The bedplate contains the lower main bear-
ing halves. Use care when handling bedplate as not
to drop or damage bearing halves. Installing main
bearing halves in the wrong position will cause
sever damage to the crankshaft.
NOTE: The bedplate has pry points cast into it. Use
these points only. The pry points are on both the
left and right sides, only the left side is shown.
(7) Carefully pry on the pry points (Fig. 54) to
loosen the bedplate then remove the bedplate.
CAUTION: When removing the crankshaft, use care
not to damage bearing surfaces on the crankshaft.
(8) Remove the crankshaft.
(9) Remove the crankshaft target wheel.
INSPECTION
NOTE: Thoroughly inspect the connecting rod bear-
ing bores and main bearing bores for scoring, blue-
ing or severe scratches. Further disassembly may
be required.If connecting rod bearing bores show damage, the
cylinder heads must be removed to service the piston
and rod assemblies. If the bedplate or the cylinder
block main bearing bores show damage the engine
must be replaced.
(1) If required, remove the main bearing halves
from the cylinder block and bedplate.
(2) Thoroughly clean the bedplate to cylinder block
sealing surfaces and main bearing bores. Remove all
oil and sealant residue.
(3) Inspect the bedplate main bearing bores for
cracks, scoring or severe blueing. If either condition
exists the engine must be replaced.
(4) Inspect the crankshaft thrust washers for scor-
ing, scratches, wear or blueing. If either condition
exist replace the thrust washer.
(5) Inspect the oil pan gasket/windage tray for
splits, tears or cracks in the gasket sealing surfaces.
Replace gasket as necessary.INSTALLATION
CAUTION: Main bearings are select fit. (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT MAIN
BEARINGS - STANDARD PROCEDURE) for proper
bearing selections.
Fig. 54 Bedplate Pry Point Location
1 - CYLINDER BLOCK
2 - BEDPLATE
3 - PRY POINT
9 - 112 ENGINE - 4.7LWJ
CRANKSHAFT (Continued)

²Tighten boltsA1± A6to 27 N´m (20 ft. lbs.)
(8) Measure crankshaft end play. (Refer to 9 -
ENGINE/ENGINE BLOCK/CRANKSHAFT - STAN-
DARD PROCEDURE).
(9) Install the connecting rods and measure side
clearance. (Refer to 9 - ENGINE/ENGINE BLOCK/
CONNECTING ROD BEARINGS - STANDARD
PROCEDURE).
(10) Position the oil pan gasket/windage tray,
using a new o-ring, install the oil pickup tube.
Torque the bolt to 28N´n (20 ft. lbs.) torque the nuts
to 28N´m (20 ft. lbs.).
(11)
Install the oil pan. Torque the retaining bolts to
15 N´m (11 ft. lbs.) in the sequence shown (Fig. 59).
(12) Install the engine (Refer to 9 - ENGINE -
INSTALLATION).
CRANKSHAFT MAIN
BEARINGS
STANDARD PROCEDUREÐCRANKSHAFT MAIN
BEARING - FITTING
MAIN BEARING JOURNAL DIAMETER
(CRANKSHAFT REMOVED)
Crankshaft removed from the cylinder block.
Clean the oil off the main bearing journal.
Determine the maximum diameter of the journal
with a micrometer. Measure at two locations 90É
apart at each end of the journal.
The maximum allowable taper is 0.008mm (0.0004
inch.) and maximum out of round is 0.005mm (0.002
inch). Compare the measured diameter with the jour-
nal diameter specification (Main Bearing Fitting
Chart). Select inserts required to obtain the specified
bearing-to-journal clearance.
Fig. 58 Bedplate Tightening Sequence
1 - BEDPLATE
2 - CYLINDER BLOCK
Fig. 59 Oil Pan Tightening Sequence
9 - 114 ENGINE - 4.7LWJ
CRANKSHAFT (Continued)

FLEX PLATE
REMOVAL
(1) Remove the transmission.
(2) Remove the bolts and flexplate.
INSTALLATION
(1) Position the flexplate onto the crankshaft and
install the bolts hand tight.
(2) Tighten the flexplate retaining bolts to 60 N´m
(45 ft. lbs.) in the sequence shown (Fig. 68).
(3) Install the transmission.
PISTON & CONNECTING ROD
DESCRIPTION
CAUTION: Do not use a metal stamp to mark con-
necting rods as damage may result, instead use ink
or a scratch awl.
The pistons are made of a high strength aluminum
alloy. The anodized top ring groove and crown has
been replaced with a coated top ring that is blue in
color on the bottom surface. Piston skirts are coated
with a solid lubricant (Molykote) to reduce friction
and provide scuff resistance. The connecting rods are
made of forged powdered metal, with a ªfractured
capº design. A pressed fit piston pin is used to attach
the piston and connecting rod on the 4.7L. The 4.7L
HO uses a full floating piston pin.
STANDARD PROCEDUREÐPISTON FITTING
(1) To correctly select the proper size piston, a cyl-
inder bore gauge, capable of reading in 0.003 mm (
.0001 in.) INCREMENTS is required. If a bore gauge
is not available, do not use an inside micrometer.
(2) Measure the inside diameter of the cylinder
bore at a point 38.0 mm (1.5 inches) below top of
bore. Start perpendicular (across or at 90 degrees) to
the axis of the crankshaft at point A and then take
an additional bore reading 90 degrees to that at point
B (Fig. 70).
(3) The coated pistons will be serviced with the
piston pin and connecting rod pre-assembled.
(4) The coating material is applied to the piston
after the final piston machining process. Measuring
the outside diameter of a coated piston will not pro-
vide accurate results (Fig. 69). Therefore measuring
the inside diameter of the cylinder bore with a dial
Bore Gauge isMANDATORY. To correctly select the
proper size piston, a cylinder bore gauge capable of
reading in 0.003 mm (.0001 in.) increments is
required.
(5) Piston installation into the cylinder bore
requires slightly more pressure than that required
for non-coated pistons. The bonded coating on the
piston will give the appearance of a line-to-line fit
with the cylinder bore.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the following components:
²Oil pan and gasket/windage tray (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - REMOVAL).
²Cylinder head covers (Refer to 9 - ENGINE/
CYLINDER HEAD/CYLINDER HEAD COVER(S) -
Fig. 68 Flexplate Tightening Sequence
1 - FLEXPLATE
Fig. 69 Moly Coated PistonÐTypical
1 - MOLY COATED
2 - MOLY COATED
9 - 118 ENGINE - 4.7LWJ

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)