DODGE RAM 2003 Service Repair Manual

CRANKSHAFT
DESCRIPTION
The crankshaft (Fig. 23) is of a cast nodular steel
splayed type design, with five main bearing journal-
s.The crankshaft is located at the bottom of the
engine block and is held in place with five main bear-
ing caps. The number 3 counterweight is the location
for journal size identification.
OPERATION
The crankshaft transfers force generated by com-
bustion within the cylinder bores to the flywheel or
flexplate.
REMOVAL
NOTE: This procedure can be done in vehicle. How-
ever the transmission must be removed first.
(1) If crankshaft is to be removed while engine is
in vehicle remove the transmission. Refer to 21 -
TRANSMISSION/TRANSAXLE.
(2) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(3) Remove the oil pump from the rear main bear-
ing cap (Refer to 9 - ENGINE/LUBRICATION/OIL
PUMP - REMOVAL).
(4) Remove the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(5) Remove the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(6) Identify rod bearing caps before removal.
Remove rod bearing caps with bearings.CAUTION: Support crankshaft before removing
main bearing caps. failure to do so will allow the
crankshaft to fall damaging the crankshaft.
(7) Using a suitable jack, support the crankshaft.
(8) Identify main bearing caps before removal.
Remove main bearing caps and bearings one at a
time.
(9) Lower the crankshaft out of the block.
(10) Remove and discard the crankshaft rear oil
seals.
(11) Remove and discard the front crankshaft oil
seal.
INSTALLATION
(1) Clean Gasket Maker residue and sealant from
the cylinder block and rear cap mating surface. Do
this before applying the MopartGasket Maker and
the installation of rear cap.
(2) Lightly oil the new upper seal lips with engine
oil.
(3) Install the new upper rear bearing oil seal with
the white paint facing towards the rear of the engine.
(4) Position the crankshaft into the cylinder block.
(5) Lightly oil the new lower seal lips with engine
oil.
(6) Install the new lower rear bearing oil seal into
the bearing cap with the white paint facing towards
the rear of the engine.
(7) Apply 5 mm (0.20 in) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 24). DO NOT over apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
Fig. 23 Crankshaft with Journal Size Identification
Fig. 24 Sealant Application to Bearing Cap
1 - MOPARTGASKET MAKER 5 mm (0.20 IN.) ON BOTH SIDES
OF REAR MAIN CAP
9 - 252 ENGINE - 5.9LDR

(8) To align the bearing cap, use cap slot, align-
ment dowel and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than 2 times for proper engagement.
(9) Clean and oil all cap bolts. Install all main
bearing caps. Install all cap bolts and alternately
tighten to 115 N´m (85 ft. lbs.) torque.
(10) Install oil pump (Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
(11) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(12) Install the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION).
(13) Position the connecting rods onto the crank-
shaft and install the rod bearing caps. Tighten the
nuts to 61 N´m (45 ft. lbs.).
(14) Apply MopartSilicone Rubber Adhesive Seal-
ant, or equivalent, at bearing cap to block joint to
provide cap to block and oil pan sealing (Fig. 25).
Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(15) Install new front crankshaft oil seal (Refer to
9 - ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - FRONT - INSTALLATION).
(16) Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
(17) If the transmission was removed, install the
transmission. Refer to 21 - TRANSMISSION/TRANS-
AXLE.CRANKSHAFT MAIN
BEARINGS
DESCRIPTION
Main bearings (Fig. 26) are located in the cylinder
block. One half of the main bearing is located in the
crankshaft main bore the other half of the matching
bearing is located in the main bearing cap. there are
five main bearings. Number three main bearing is
flanged, this flange controls crankshaft thrust.
OPERATION
The main bearings encircle the crankshaft main
bearing journals, this aligns the crankshaft to the
centerline of the engine and allows the crankshaft to
turn without wobbling or shaking therefore eliminat-
ing vibration. The main bearings are available in
standard and undersizes.
STANDARD PROCEDUREÐCRANKSHAFT MAIN
BEARING FITTING
Bearing caps are not interchangeable and should
be marked at removal to ensure correct assembly.
Upper and lower bearing halves are NOT inter-
changeable. Lower main bearing halves of No.2 and 4
are interchangeable.
Upper and lower No.3 bearing halves are flanged
to carry the crankshaft thrust loads. They are NOT
interchangeable with any other bearing halves in the
engine (Fig. 27). Bearing shells are available in stan-
dard and the following undersizes: Never install an
undersize bearing that will reduce clearance below
specifications.
Fig. 25 Apply Sealant to Bearing Cap to Block Joint
1 - MOPAR SILICONE RUBBER ADHESIVE SEALANT NOZZLE
TIP
2 - SEALANT APPLIED
3 - CYLINDER BLOCK
4 - REAR MAIN BEARING CAP
Fig. 26 Main Bearing Orientation
DRENGINE - 5.9L 9 - 253
CRANKSHAFT (Continued)

Main Bearing Undersize Availability List
²0.25 mm (0.001 inch)
²0.051 mm (0.002 inch)
²0.076 mm (0.003 inch)
²0.254 mm (0.010 inch)
²0.305 mm (0.012 inch)
REMOVAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump from the rear main bear-
ing cap (Refer to 9 - ENGINE/LUBRICATION/OIL
PUMP - REMOVAL).
(3) Identify bearing caps before removal. Remove
bearing caps one at a time.
(4) Remove upper half of bearing by inserting
Crankshaft Main Bearing Remover/Installer Tool
C-3059 into the oil hole of crankshaft (Fig. 28).
(5) Slowly rotate crankshaft clockwise, forcing out
upper half of bearing shell.
INSTALLATION
Only one main bearing should be selectively fitted
while all other main bearing caps are properly tight-
ened. All bearing capbolts removed during service
procedures are to be cleaned and oiled before instal-
lation.
When installing a new upper bearing shell, slightly
chamfer the sharp edges from the plain side.
(1) Start bearing in place, and insert Crankshaft
Main Bearing Remover/Installer Tool C-3059 into oil
hole of crankshaft (Fig. 28).
(2) Slowly rotate crankshaft counterclockwise slid-
ing the bearing into position. Remove Tool C-3059.
(3) Install the bearing caps. Clean and oil the
bolts. Tighten the capbolts to 115 N´m (85 ft. lbs.)
torque.
(4) Install the oil pump (Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).(5) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(6) Start engine check for leaks.
CRANKSHAFT OIL SEAL -
FRONT
DESCRIPTION
The crankshaft front seal is a one piece viton seal
with a steel housing. The front seal is located in the
engine front cover.
OPERATION
The crankshaft seals prevent oil from leaking from
around the crankshaft, either from the rear of the
engine or from the engine front cover.
REMOVAL
The oil seal can be replaced without removing the
timing chain cover, provided that the cover is not
misaligned.
(1) Disconnect the negative cable from the battery.
(2) Remove vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(3) If front seal is suspected of leaking, check front
oil seal alignment to crankshaft. The seal installa-
tion/alignment Tool 6635, should fit with minimum
interference. If tool does not fit, the cover must be
removed and installed properly.
Fig. 27 Main Bearing
Fig. 28 Upper Main Bearing Removal and
Installation with Tool C-3059
1 - SPECIAL TOOL C-3059
2 - BEARING
3 - SPECIAL TOOL C-3059
4 - BEARING
9 - 254 ENGINE - 5.9LDR
CRANKSHAFT MAIN BEARINGS (Continued)

(4) Place a suitable tool behind the lips of the oil
seal to pry the oil seal outward. Be careful not to
damage the crankshaft seal bore of cover.
INSTALLATION
(1) Place the smaller diameter of the oil seal over
Front Oil Seal Installation Tool 6635 (Fig. 29). Seat
the oil seal in the groove of the tool.
(2) Position the seal and tool onto the crankshaft
(Fig. 30).
(3) Using the vibration damper bolt, tighten the
bolt to draw the seal into position on the crankshaft
(Fig. 31).
(4) Remove the vibration damper bolt and seal
installation tool.
(5) Inspect the seal flange on the vibration
damper.
(6) Install the vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION).
(7) Connect the negative cable to the battery.
CRANKSHAFT OIL SEAL -
REAR
DESCRIPTION
The crankshaft rear seal is a two piece viton seal.
One part of the two piece rear seal is located in a slot
in the cylinder block oppsite the crankshaft main
bearing cap, the second part of the two piece seal is
located in the main bearing cap itself.
OPERATION
The crankshaft seals prevent oil from leaking from
around the crankshaft, either from the rear of the
engine or from the engine front cover.
REMOVAL
The service seal is a two piece, Viton seal. The
upper seal half can be installed with crankshaft
removed from engine or with crankshaft installed.
When a new upper seal is installed, install a new
Fig. 29 Placing Oil Seal on Installation Tool 6635
1 - CRANKSHAFT FRONT OIL SEAL
2 - INSTALL THIS END INTO SPECIAL TOOL 6635
Fig. 30 Position Tool and Seal onto Crankshaft
1 - SPECIAL TOOL 6635
2 - OIL SEAL
3 - TIMING CHAIN COVER
Fig. 31 Installing Oil Seal
1 - SPECIAL TOOL 6635
2 - TIMING CHAIN COVER
DRENGINE - 5.9L 9 - 255
CRANKSHAFT OIL SEAL - FRONT (Continued)

lower seal. The lower seal half can be installed only
with the rear main bearing cap removed.
UPPER SEAL ÐCRANKSHAFT REMOVED
(1) Remove the crankshaft (Refer to 9 - ENGINE/
ENGINE BLOCK/CRANKSHAFT - REMOVAL). Dis-
card the old upper seal.
UPPER SEALÐCRANKSHAFT INSTALLED
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump (Refer to 9 - ENGINE/
LUBRICATION/OIL PUMP - REMOVAL).
(3) Remove the rear main bearing cap. Remove
and discard the old lower oil seal.
(4) Carefully remove and discard the old upper oil
seal.
LOWER SEAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump (Refer to 9 - ENGINE/
LUBRICATION/OIL PUMP - REMOVAL).
(3) Remove the rear main bearing cap and discard
the old lower seal.
INSTALLATION
The service seal is a two piece, Viton seal. The
upper seal half can be installed with crankshaft
removed from engine or with crankshaft installed.
When a new upper seal is installed, install a new
lower seal. The lower seal half can be installed only
with the rear main bearing cap removed.
UPPER SEAL ÐCRANKSHAFT REMOVED
(1) Clean the cylinder block rear cap mating sur-
face. Be sure the seal groove is free of debris. Check
for burrs at the oil hole on the cylinder block mating
surface to rear cap.
(2) Lightly oil the new upper seal lips with engine
oil.
(3) Install the new upper rear bearing oil seal with
the white paint facing toward the rear of the engine.
(4) Position the crankshaft into the cylinder block.
(5)
Lightly oil the new lower seal lips with engine oil.
(6) Install the new lower rear bearing oil seal into
the bearing cap with the white paint facing towards
the rear of the engine.
(7) Apply 5 mm (0.20 in.) drop of MopartGasket
Maker, or equivalent, on each side of the rear mainbearing cap (Fig. 32). DO NOT over-apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(8) To align the bearing cap, use cap slot, align-
ment dowel, and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than two times for proper engagement.
(9) Clean and oil all cap bolts. Install all main
bearing caps. Install all cap bolts and alternately
tighten to 115 N´m (85 ft. lbs.) torque.
(10) Install oil pump (Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
(11) Apply MopartGEN II Silicone Rubber Adhe-
sive Sealant, or equivalent, at bearing cap-to-block
joint to provide cap to block and oil pan sealing (Fig.
33). Apply enough sealant so that a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(12) Install new front crankshaft oil seal (Refer to
9 - ENGINE/ENGINE BLOCK/CRANKSHAFT OIL
SEAL - FRONT - INSTALLATION).
(13) Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
Fig. 32 Sealant Application to Bearing Cap
1 - MOPAR SILICONE RUBBER ADHESIVE SEALANT SLOTS
2 - MOPARTGASKET MAKER (OR EQUIVALENT)
3 - CAP ALIGNMENT SLOT
4 - REAR MAIN BEARING CAP
9 - 256 ENGINE - 5.9LDR
CRANKSHAFT OIL SEAL - REAR (Continued)

UPPER SEALÐCRANKSHAFT INSTALLED
(1) Clean the cylinder block mating surfaces before
oil seal installation. Check for burrs at the oil hole on
the cylinder block mating surface to rear cap.
(2) Lightly oil the new upper seal lips with engine
oil. To allow ease of installation of the seal, loosen at
least the two main bearing caps forward of the rear
bearing cap.
(3) Rotate the new upper seal into the cylinder
block, being careful not to shave or cut the outer sur-
face of the seal. To ensure proper installation, use the
installation tool provided with the kit. Install the
new seal with the white paint facing toward the rear
of the engine.
(4) Install the new lower rear bearing oil seal into
the bearing cap with the white paint facing toward
the rear of the engine.
(5) Apply 5 mm (0.20 in.) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 32). DO NOT over-apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application. Be sure the white paint faces
toward the rear of the engine.
(6) To align the bearing cap, use cap slot, align-
ment dowel, and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than two times for proper engagement.(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten ALL cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PUMP - INSTALLATION).
(9) Apply MopartGEN II Silicone Rubber Adhe-
sive Sealant, or equivalent, at bearing cap-to-block
joint to provide cap-to-block and oil pan sealing (Fig.
33). Apply enough sealant until a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
LOWER SEAL
(1) Clean the rear main cap mating surfaces
including the oil pan gasket groove.
(2) Carefully install a new upper seal. Refer to
UPPER SEALÐCRANKSHAFT INSTALLED.
(3) Lightly oil the new lower seal lips with engine
oil.
(4) Install a new lower seal in bearing cap with
the white paint facing the rear of engine.
(5) Apply 5 mm (0.20 in.) drop of MopartGasket
Maker, or equivalent, on each side of the rear main
bearing cap (Fig. 32). DO NOT over-apply sealant or
allow the sealant to contact the rubber seal. Assem-
ble bearing cap to cylinder block immediately after
sealant application.
(6) To align the bearing cap, use cap slot, align-
ment dowel, and cap bolts. DO NOT remove excess
material after assembly. DO NOT strike rear cap
more than two times for proper engagement.
(7) Install the rear main bearing cap with cleaned
and oiled cap bolts. Alternately tighten the cap bolts
to 115 N´m (85 ft. lbs.) torque.
(8) Install oil pump (Refer to 9 - ENGINE/LUBRI-
CATION/OIL PUMP - INSTALLATION).
(9) Apply MopartGEN II Silicone Rubber Adhe-
sive Sealant, or equivalent, at bearing cap-to-block
joint to provide cap to block and oil pan sealing.
Apply enough sealant so that a small amount is
squeezed out. Withdraw nozzle and wipe excess seal-
ant off the oil pan seal groove.
(10) Immediately install the oil pan (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
Fig. 33 Apply Sealant to Bearing Cap-to-Block Joint
1 - MOPAR SILICONE RUBBER ADHESIVE SEALANT NOZZLE
TIP
2 - SEALANT APPLIED
3 - CYLINDER BLOCK
4 - REAR MAIN BEARING CAP
DRENGINE - 5.9L 9 - 257
CRANKSHAFT OIL SEAL - REAR (Continued)

DISTRIBUTOR BUSHING
REMOVAL
(1) Remove distributor (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/DISTRIBUTOR - REMOVAL).
(2) Remove the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL).
(3) Insert Distributor Drive Shaft Bushing Puller
Tool C-3052 into old bushing and thread down until a
tight fit is obtained (Fig. 34).
(4) Hold puller screw and tighten puller nut until
bushing is removed.
INSTALLATION
(1) Slide new bushing over burnishing end of Dis-
tributor Drive Shaft Bushing Driver/Burnisher Tool
C-3053. Insert the tool and bushing into the bore.
(2) Drive bushing and tool into position, using a
hammer (Fig. 35).
(3) As the burnisher is pulled through the bushing,
the bushing is expanded tight in the block and bur-
nished to correct size (Fig. 36).DO NOT ream this
bushing.CAUTION: This procedure MUST be followed when
installing a new bushing or seizure to shaft may
occur.
(4) Install the intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(5) Install the distributor (Refer to 8 - ELECTRI-
CAL/IGNITION CONTROL/DISTRIBUTOR -
INSTALLATION).
HYDRAULIC LIFTERS
DIAGNOSIS AND TESTINGÐHYDRAULIC
TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, check the oil pressure. If vehicle
has no oil pressure gauge, install a reliable gauge at
the pressure sending-unit. The pressure should be
between 207-552 kPa (30-80 psi) at 3,000 RPM.
Check the oil level after the engine reaches normal
operating temperature. Allow 5 minutes to stabilize
oil level, check dipstick. The oil level in the pan
should never be above the FULL mark or below the
ADD OIL mark on dipstick. Either of these two con-
ditions could be responsible for noisy tappets.
OIL LEVEL
HIGH
If oil level is above the FULL mark, it is possible
for the connecting rods to dip into the oil. With the
engine running, this condition could create foam in
the oil pan. Foam in oil pan would be fed to the
hydraulic tappets by the oil pump causing them to
lose length and allow valves to seat noisily.
LOW
Low oil level may allow oil pump to take in air.
When air is fed to the tappets, they lose length,
which allows valves to seat noisily. Any leaks on
Fig. 34 Distributor Driveshaft Bushing Removal
1 - SPECIAL TOOL C-3052
2 - BUSHING
Fig. 35 Distributor Driveshaft Bushing Installation
1 - SPECIAL TOOL C-3053
2 - BUSHING
Fig. 36 Burnishing Distributor Driveshaft Bushing
1 - SPECIAL TOOL C-3053
2 - BUSHING
9 - 258 ENGINE - 5.9LDR

intake side of oil pump through which air can be
drawn will create the same tappet action. Check the
lubrication system from the intake strainer to the
pump cover, including the relief valve retainer cap.
When tappet noise is due to aeration, it may be
intermittent or constant, and usually more than one
tappet will be noisy. When oil level and leaks have
been corrected, operate the engine at fast idle. Run
engine for a sufficient time to allow all of the air
inside the tappets to be bled out.
TAPPET NOISE DIAGNOSIS
(1) To determine source of tappet noise, operate
engine at idle with cylinder head covers removed.
(2) Feel each valve spring or rocker arm to detect
noisy tappet. The noisy tappet will cause the affected
spring and/or rocker arm to vibrate or feel rough in
operation.
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy tappets. If such is
the case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in the
tappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
(3) Valve tappet noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger, or by the
plunger partially sticking in the tappet body cylinder.
The tappet should be replaced. A heavy click is
caused by a tappet check valve not seating, or by for-
eign particles wedged between the plunger and the
tappet body. This will cause the plunger to stick in
the down position. This heavy click will be accompa-
nied by excessive clearance between the valve stem
and rocker arm as valve closes. In either case, tappet
assembly should be removed for inspection and clean-
ing.
(4) The valve train generates a noise very much
like a light tappet noise during normal operation.
Care must be taken to ensure that tappets are mak-
ing the noise. If more than one tappet seems to be
noisy, it's probably not the tappets.
LEAK-DOWN TEST
After cleaning and inspection, test each tappet for
specified leak-down rate tolerance to ensure zero-lash
operation (Fig. 37).
Swing the weighted arm of the hydraulic valve tap-
pet tester away from the ram of the Universal Leak-
Down Tester.
(1) Place a 7.925-7.950 mm (0.312-0.313 inch)
diameter ball bearing on the plunger cap of the tap-
pet.(2) Lift the ram and position the tappet (with the
ball bearing) inside the tester cup.
(3) Lower the ram, then adjust the nose of the ram
until it contacts the ball bearing. DO NOT tighten
the hex nut on the ram.
(4) Fill the tester cup with hydraulic valve tappet
test oil until the tappet is completely submerged.
(5) Swing the weighted arm onto the push rod and
pump the tappet plunger up and down to remove air.
When the air bubbles cease, swing the weighted arm
away and allow the plunger to rise to the normal
position.
(6) Adjust the nose of the ram to align the pointer
with the SET mark on the scale of the tester and
tighten the hex nut.
(7) Slowly swing the weighted arm onto the push
rod.
(8) Rotate the cup by turning the handle at the
base of the tester clockwise one revolution every 2
seconds.
(9) Observe the leak-down time interval from the
instant the pointer aligns with the START mark on
the scale until the pointer aligns with the 0.125
mark. A normally functioning tappet will require
20-110 seconds to leak-down. Discard tappets with
leak-down time interval not within this specification.
REMOVAL
(1) Remove the air cleaner assembly and air in-let
hose.
(2) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
Fig. 37 Leak-Down Tester
1 - POINTER
2 - WEIGHTED ARM
3 - RAM
4 - CUP
5 - HANDLE
6 - PUSH ROD
DRENGINE - 5.9L 9 - 259
HYDRAULIC LIFTERS (Continued)

(3) Remove rocker assembly and push rods (Refer
to 9 - ENGINE/CYLINDER HEAD/ROCKER ARM /
ADJUSTER ASSY - REMOVAL). Identify push rods
to ensure installation in original locations.
(4) Remove intake manifold (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - REMOVAL).
(5) Remove yoke retainer and aligning yokes.
(6) Slide Hydraulic Tappet Remover/Installer Tool
C-4129-A through opening in cylinder head and seat
tool firmly in the head of tappet.
(7) Pull tappet out of bore with a twisting motion.
If all tappets are to be removed, identify tappets to
ensure installation in original location.
(8) If the tappet or bore in cylinder block is scored,
scuffed, or shows signs of sticking, ream the bore to
next oversize. Replace with oversize tappet.
CLEANING
Clean tappet with a suitable solvent. Rinse in hot
water and blow dry with a clean shop rag or com-
pressed air.
INSTALLATION
(1) Lubricate tappets with MopartEngine Oil
Supplement or equivalent.
(2) Install tappets and push rods in their original
positions. Ensure that the oil feed hole in the side of
the tappet body faces up (away from the crankshaft).
(3) Install aligning yokes with ARROW toward
camshaft.
(4) Install yoke retainer. Tighten the bolts to 23
N´m (200 in. lbs.) torque. Install intake manifold
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - INSTALLATION).
(5) Install rocker arms (Refer to 9 - ENGINE/CYL-
INDER HEAD/ROCKER ARM / ADJUSTER ASSY -
INSTALLATION).
(6) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(7) Install air cleaner assembly and air in-let hose.
(8) Start and operate engine. Warm up to normal
operating temperature.
CAUTION: To prevent damage to valve mechanism,
engine must not be run above fast idle until all
hydraulic tappets have filled with oil and have
become quiet.
PISTON & CONNECTING ROD
DESCRIPTION
The pistons are made of aluminum and have three
ring grooves, the top two grooves are for the compres-
sion rings and the bottom groove is for the oil control
ring. The connecting rods are forged steel and are
coined prior to heat treat. The piston pins are press
fit.
STANDARD PROCEDURE - PISTON FITTING
Piston and cylinder wall must be clean and dry.
Specified clearance between the piston and the cylin-
der wall is 0.013-0.038 mm (0.0005-0.0015 inch) at
21ÉC (70ÉF).
Piston diameter should be measured at the top of
skirt, 90É to piston pin axis. Cylinder bores should be
measured halfway down the cylinder bore and trans-
verse to the engine crankshaft center line.
Pistons and cylinder bores should be measured at
normal room temperature, 21ÉC (70ÉF).
Check the pistons for taper and elliptical shape
before they are fitted into the cylinder bore (Fig. 38).
Fig. 38 Piston Measurements
1 - 49.53 mm
(1.95 IN.)
9 - 260 ENGINE - 5.9LDR
HYDRAULIC LIFTERS (Continued)

PISTON MEASUREMENT CHART
PISTON A DIA = PISTON BORE
SIZE DIAMETER DIAMETER
MIN. MAX. MIN. MAX.
mm
(in.)mm
(in.)mm
(in.)mm (in.)
AÐÐÐ Ð
B101.580 101.592 101.605 101.618
(3.9992) (3.9997) (4.0002) (4.0007)
C101.592 101.605 101.618 101.630
(3.9997) (4.0002) (4.0007) (4.0012)
D101.605 101.618 101.630 101.643
(4.0002) (4.0007) (4.0012) (4.0017)
EÐÐÐ Ð
DESCRIPTION SPECIFICATION
PISTON PIN BORE 25.007 - 25.015 mm
(.9845 - .9848 in.)
RING GROOVE
HEIGHT
OIL RAIL 4.033 - 4.058 mm
(.1588 - .1598 in.)
COMPRESSION
RAIL1.529 - 1.554 mm
(.0602 - .0612 in.)
TOTAL FINISHED 470.8   2 grams
WEIGHT (16.607   .0706 ounces)
REMOVAL
(1) Remove the engine from the vehicle (Refer to 9
- ENGINE - REMOVAL).
(2) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(3) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(4) Remove top ridge of cylinder bores with a reli-
able ridge reamer before removing pistons from cyl-
inder block. Be sure to keep tops of pistons covered
during this operation.
(5) Be sure each connecting rod and connecting rod
cap is identified with the cylinder number. Remove
connecting rod cap. Install connecting rod bolt guide
set on connecting rod bolts.(6) Pistons and connecting rods must be removed
from top of cylinder block. When removing the
assemblies from the engine, rotate crankshaft so that
the connecting rod is centered in cylinder bore and at
BDC.Be careful not to nick crankshaft journals.
(7) After removal, install bearing cap on the mat-
ing rod.
CLEANING
Clean the piston and connecting rod assembly
using a suitable solvent.
INSPECTION
Check the connecting rod journal for excessive
wear, taper and scoring (Refer to 9 - ENGINE/EN-
GINE BLOCK/CONNECTING ROD BEARINGS -
STANDARD PROCEDURE).
Check the connecting rod for signs of twist or bend-
ing.
Check the piston for taper and elliptical shape
before it is fitted into the cylinder bore (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON & CONNECT-
ING ROD - STANDARD PROCEDURE).
Check the piston for scoring, or scraping marks in
the piston skirts. Check the ring lands for cracks
and/or deterioration.
INSTALLATION
(1) Be sure that compression ring gaps are stag-
gered so that neither is in line with oil ring rail gap.
(2) Before installing the ring compressor, be sure
the oil ring expander ends are butted and the rail
gaps located properly (Fig. 39).
Fig. 39 Proper Ring Installation
1 - OIL RING SPACER GAP
2 - SECOND COMPRESSION RING GAP OIL RING RAIL GAP
(TOP)
3 - OIL RING RAIL GAP (BOTTOM)
4 - TOP COMPRESSION RING GAP
DRENGINE - 5.9L 9 - 261
PISTON & CONNECTING ROD (Continued)