clock DODGE RAM 2003 Service Owners Manual

ring tool to keep the engine from rotating during
tightening operation.
(11) Install the fan support/hub assembly and
torque bolts to 32 N´m (24 ft. lbs.).
(12) Install hydraulic pump.
(13) Install accessory drive belt tensioner. Torque
bolt to 43 Nm (32 ft.lbs.).
(14) Install cooling fan (Refer to 7 - COOLING/EN-
GINE/RADIATOR FAN - INSTALLATION).
(15) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(16) Refill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(17) Connect battery negative cables.
(18) Start engine and check for oil leaks.
CRANKSHAFT OIL SEAL -
REAR
REMOVAL
(1) Disconnect the battery negative cables.
(2) Remove the transmission and transfer case (if
equipped).
(3) Remove the clutch cover and disc (if manual
transmission equipped) (Refer to 6 - CLUTCH/
CLUTCH DISC - REMOVAL).
(4) Remove the flywheel or converter drive plate.
(5) Drill holes 180É apart into the seal. Be careful
not to contact the drill against the crankshaft.
(6) Install #10 sheet metal screws in the drilled
holes and remove the rear seal with a slide hammer
(Fig. 73).
INSTALLATION
CAUTION: The seal lip and the sealing surface on
the crankshaft must be free from all oil residue to
prevent seal leaks. The crankshaft and seal sur-
faces must be completely dry when the seal is
installed. Use a soap and water solution on outside
diameter of seal to ease assembly.
(1) Clean the crankshaft journal with a suitable
solvent and dry with a clean shop towel or com-
pressed air. Wipe the inside bore of the crankshaft
seal retainer with a clean shop towel.
(2) Inspect the crankshaft journal for gouges,
nicks, or other imperfections. If the seal groove in the
crankshaft is excessively deep, install the new seal
1/8º deeper into the retainer bore, or obtain a crank-
shaft wear sleeve that is available in the aftermar-
ket.
(3) Install the seal pilot and new seal, provided in
the replacement kit, onto the crankshaft.
(4) Remove the seal pilot.
(5) Install the installation tool over crankshaft.
(6) Using a ball peen hammer, strike the tool at
the 12, 3, 6, and 9 o'clock positions until the align-
ment tool bottoms out on the retainer (Fig. 74).
(7) Install the flywheel or converter drive plate.
Tighten the bolts to 137 N´m (101 ft. lbs.) torque.
(8) Install the clutch cover and disc (if equipped)
(Refer to 6 - CLUTCH/CLUTCH DISC - INSTALLA-
TION).
(9) Install the transmission and transfer case (if
equipped).
(10) Lower vehicle.
Fig. 73 Crankshaft Rear Seal Removal
1 - NO. 10 SCREW
2 - REAR SEAL
3 - CRANKSHAFT
4 - SLIDE HAMMER
Fig. 74 Seal Installation Using Alignment Tool and
Hammer
1 - SEAL PILOT TOOL
2 - INSTALLATION TOOL
3 - SEAL
4 - RETAINER
DRENGINE 5.9L DIESEL 9 - 325
CRANKSHAFT OIL SEAL - FRONT (Continued)

(11) Connect battery negative cables.
(12) Check engine oil level and adjust, if necessary.
(13) Start engine and check for oil leaks.
CRANKSHAFT REAR OIL SEAL
RETAINER
REMOVAL
(1) Disconnect the battery negative cables.
(2) Raise vehicle on hoist.
(3) Remove the oil pan drain plug and drain the
engine oil. Re-install plug and torque to 50 N´m (44
ft. lbs.) torque.
(4) Remove transmission and transfer case (if
equipped) from vehicle.
(5) Remove flywheel or torque converter drive
plate.
(6) Disconnect starter cables from starter motor.
(7) Remove starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL)
and transmission adapter plate assembly.
(8) Remove four (4) oil pan rear bolts. Slide a
feeler guage between the seal retainer and oil pan
gasket to break the seal.
(9) Remove the six (6) retainer-to-block bolts (Fig.
75).
(10) Remove the rear seal retainer and gasket
(Fig. 75).
(11) Support the seal retainer and drive out the
crankshaft seal with a hammer and suitable punch.
INSTALLATION
(1) If using the old seal retainer, the crankshaft
seal must be replaced.(2) Inspect oil pan gasket for nickes or cuts. If gas-
ket is damaged, the oil pan must be removed and
gasket must be replaced. Wipe oil pan gasket dry and
apply light coating of RTV.
(3) Using the retainer alignment/seal installation
tool provided in the seal service kit, install the align-
ment tool into the retainer and install to the cylinder
block (Fig. 76), using a new gasket. Tighten the six
(6) mounting bolts by hand.
(4) The seal alignment tool is used to align rear
cover properly. Starting with the center two bolts,
tighten the retainer in a circular pattern to 10 N´m
(89 in. lbs.). Remove the alignment tool.
CAUTION: The seal lip and the sealing surface on
the crankshaft must be free from all oil residue to
prevent seal leaks. The crankshaft and seal sur-
faces must be completely dry when the seal is
installed. Use a soap and water solution on outside
diameter of seal to ease assembly.
(5) Make sure the provided seal pilot is installed
into the new crankshaft seal. Use the alignment/in-
stallation tool and press the seal onto the crankshaft
(Fig. 77). Alternately drive the seal at the 12, 3, 6
and 9 o'clock positions.
(6) Remove the alignment tool and trim the
retainer gasket even with the oil pan mounting sur-
face (Fig. 78).
(7) Remove the seal pilot.
(8) Apply a small amount of MopartSilicone Rub-
ber Adhesive Sealant to the oil pan rail T-joints.
(9) Install the four (4) oil pan rear mounting bolts
and torque to 28 N´m (21 ft. lbs.).
(10) Install new rectangular ring seal for cam bore.
Fig. 75 Crankshaft Rear Seal Retainer and Gasket
1 - RETAINER
2 - GASKET
3 - BOLT
Fig. 76 Aligning Seal Retainer with Alignment/
Installation Tool
1 - ALIGNMENT / INSTALLATION TOOL
2 - SEAL RETAINER
9 - 326 ENGINE 5.9L DIESELDR
CRANKSHAFT OIL SEAL - REAR (Continued)

(8) Use clean engine oil to lubricate the threads
and under the heads of the connecting rod bolts.
(9)For machined connecting rods,the number
stamped on the rod cap at the parting line must
match and be installed towards the intake or cam-
shaft side of the engine (Fig. 97).For fractured/
split type connecting rods,the long end of the rod
must be installed towards the intake side of the
engine.
(a) The connecting rod split/face must face
toward the same side as the piston notch feature
on the skirt. The split face will face toward the oil
cooler side of the engine if properly installed.
(10) Install the rod cap and bolts to the connecting
rod. Tighten the connecting rod bolts evenly in 3
steps.
²Tighten the bolts to 30 N´m (22 ft. lbs.) torque.
²Tighten the bolts to 60 N´m (44 ft. lbs.) torque.
²Rotate 60É clockwise.
(11) The crankshaft must rotate freely. Check for
freedom of rotation as the caps are installed. If the
crankshaft does not rotate freely, check the installa-
tion of the rod bearing and the bearing size.
(12) Measure the side clearance between the con-
necting rod and the crankshaft (Fig. 98). DO NOT
measure the clearance between the cap and crank-
shaft.
(13) Install J-jet piston cooling nozzles if equipped.
(14) Install block stiffener. Torque to 43 N´m (32 ft.
lbs.).
(15) Install the suction tube and oil pan (Refer to 9
- ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).(16) Install the cylinder head onto the engine
(Refer to 9 - ENGINE/CYLINDER HEAD - INSTAL-
LATION).
(17) Install a new filter and fill the crankcase with
new engine oil.
(18) Connect the battery negative cables and start
engine.
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING
(1) Determine the piston diameter and obtain the
appropriate ring set. The piston rings can be identi-
fied as shown in (Fig. 99).
Fig. 97 Correct Rod Cap Installation
Fig. 98 Side Clearance between Connecting
Rod/Crankshaft
1 - FEELER GAUGE
´Minimum 0.33 mm (.013 inch)
´MAX. 0.10mm (.004 inch)
Fig. 99 Piston Ring Identification
DRENGINE 5.9L DIESEL 9 - 333
PISTON & CONNECTING ROD (Continued)

OIL PRESSURE RELIEF VALVE
REMOVAL
(1) Disconnect the battery negative cables.
(2) Remove the threaded plug, spring and plunger
(Fig. 114). Insert a finger or a seal pick to lift the
plunger from the bore.
NOTE: If the plunger is stuck in the bore, it will be
necessary to remove the filter head.
CLEANING
(1) Clean the regulator spring and plunger with a
suitable solvent and blow dry with compressed air. If
the plunger bore requires cleaning, it is necessary to
remove the oil filter head to avoid getting debris into
the engine.
INSPECTION
Inspect the plunger and plunger bore for cracks
and excessive wear. Polished surfaces are acceptable.
Verify that the plunger moves freely in the bore.
Check the spring for height and load limitations
(Fig. 115). Replace the spring if out of limits shown
in the figure.
INSTALLATION
(1) Install the plunger, spring, and plug as shown
in (Fig. 114). Tighten the plug to 80 N´m (60 ft. lbs.)
torque.
(2) Connect the battery negative cables.
(3) Start the engine and verify that it has oil pres-
sure.
OIL PRESSURE SENSOR/
SWITCH
REMOVAL
(1) Disconnect the battery negative cables.
(2) Disconnect the oil pressure switch connector.
(3) Using a suitable socket, remove the oil pres-
sure switch from the block (counter-clockwise).
INSTALLATION
(1) If the switch is not being replaced, replace and
lubricate the o-ring.
(2) Install the oil pressure switch and tighten to
18 N´m (159 in. lbs.) torque.
(3) Connect oil pressure switch connector.
(4) Connect the battery negative cables.
(5) Start engine and check for oil leaks at the
switch.
OIL PUMP
REMOVAL
(1) Disconnect the battery negative cables.
(2) Remove fan/drive assembly (Refer to 7 - COOL-
ING/ENGINE/RADIATOR FAN - REMOVAL).
(3) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(4) Remove the fan support/hub assembly.
(5) Remove crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL) and speed indicator ring.
(6) Remove hydraulic pump.
(7) Remove accessory drive belt tensioner.
(8) Remove the gear housing cover (Refer to 9 -
ENGINE/VALVE TIMING/GEAR HOUSING COVER
- REMOVAL).
Fig. 114 Oil Pressure Regulator
1 - OIL FILTER
2 - PLUG
3 - GASKET
4 - SPRING
5 - VALVE
Fig. 115 Oil Pressure Regulator Spring Check
DRENGINE 5.9L DIESEL 9 - 343

(8) Install the oil drain tube and a new gasket to
the turbocharger. Tighten the drain tube bolts to 24
N´m (18 ft. lbs.) torque.
(9)Pre-lube the turbocharger.Pour 50 to 60 cc
(2 to 3 oz.) clean engine oil in the oil supply line fit-
ting on the turbo. Rotate the turbocharger impeller
by hand to distrubute the oil thoroughly.
(10) Install and tighten the oil supply line fitting
nut to 24 N´m (18 ft. lbs.) torque.
(11) Position the charge air cooler inlet pipe to the
turbocharger. With the clamp in position, tighten the
clamp nut to 8 N´m (72 in. lbs.) torque.
(12) Position the air inlet hose to the turbocharger.
Tighten the clamp to 8 N´m (72 in. lbs.) torque.
(13) Raise vehicle on hoist.
(14) Connect the exhaust pipe to the turbocharger
and tighten the bolts to 34 N´m (25 ft. lbs.) torque.
(15) Lower the vehicle.
(16) Connect the battery negative cables.
(17) Start the engine to check for leaks.
VALVE TIMING
STANDARD PROCEDURE - TIMING
VERIFICATION
(1) Remove the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(2) Remove fuel injector from cylinder number
1(Refer to 14 - FUEL SYSTEM/FUEL INJECTION/
FUEL INJECTOR - REMOVAL).
(3) Using Special Tool 7471B rotate the engine
until the TDC mark on the damper is at 12 o'clock.
(4) Using a 8 in.x 1/4 in. dowel rod inserted into
cylinder number 1, rock the crankshaft back and
forth to verify piston number 1 is at TDC.
(5) With cylinder number still at TDC, inspect the
keyway on the crankshaft gear for proper alignment
(12 o'clock position).
(6) If the keyway is not at 12 o'clock position
replace the crankshaft gear assembly.
(7) If the keyway is at 12 o'clock position, remove
front gear cover and verify timing mark alignment
between the camshaft gear and crankshaft gear, if
not aligned inspect keyway on camshaft gear.
(8) Inspect keyway on camshaft gear for proper
alignment with the key in the camshaft, if alignment
is off replace the camshaft/gear assembly.
(9) If timing marks alignment is off and no dam-
age is found at either the crankshaft or camshaft
gear keyways, realign timing marks as necessary.
GEAR HOUSING
REMOVAL
(1) Disconnect the battery negative cables.
(2) Raise vehicle on hoist.
(3) Partially drain engine coolant into container
suitable for re-use (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(4) Lower vehicle.
(5) Remove radiator upper hose.
(6) Disconnect coolant recovery bottle hose from
radiator filler neck and lift bottle off of fan shroud.
(7) Disconnect windshield washer pump supply
hose and electrical connections and lift washer bottle
off of fan shroud.
(8) Remove lower fan shroud fasteners. Disconnect
fan drive wire harness.
(9) Remove the upper fan shroud-to-radiator
mounting bolts.
(10) Remove viscous fan/drive assembly (Refer to 7
- COOLING/ENGINE/RADIATOR FAN - REMOVAL).
(11) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(12) Remove the cooling fan support/hub from the
front of the engine.
(13) Raise the vehicle on hoist.
(14) Remove the crankshaft damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL) and speed indicator ring.
(15) Lower the vehicle.
(16) Remove the hydraulic pump.
(17) Remove the accessory drive belt tensioner.
(18) Remove the gear cover-to-housing bolts and
gently pry the cover away from the housing, taking
care not to mar the gasket surfaces.
(19) Remove the fuel injection pump (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/FUEL INJEC-
TION PUMP - REMOVAL).
(20) Disconnect the camshaft position sensor con-
nector.
(21) Disconnect and remove engine speed sensor.
(22) Remove the camshaft (Refer to 9 - ENGINE/
ENGINE BLOCK/CAMSHAFT & BEARINGS (IN
BLOCK) - REMOVAL).
(23) Remove the six front oil pan fasteners.
(24) Remove the gear housing fasteners.
NOTE: Use care when removing the gear housing,
to avoid damage to the oil pan gasket, as the gas-
ket will be reused if it is not damaged.
(25) Slide a feeler gauge between the gear housing
and oil pan gasket, to break the gasket seal.
(26) Remove the gear housing and gasket.
9 - 348 ENGINE 5.9L DIESELDR
EXHAUST MANIFOLD (Continued)

INSTALLATION
When a crankshaft is replaced, all main and con-
necting rod bearings should be replaced with new
bearings. Therefore, selective fitting of the bearings
is not required when a crankshaft and bearings are
replaced.
NOTE: Lubricate crankshaft main bearings with
clean engine oil.
(1) Position upper main bearings into block.
(2) Position the crankshaft into the cylinder block.
(3) Lubricate the main journals with clean engine
oil. Install upper main bearings, caps and bolts. Fol-
low the 2 step tightening sequence, starting with
main bearing cap 1.
(4) Lubricate the connecting rod bearings and jour-
nals with clean engine oil. Carefully install connect-
ing rods to the crankshaft.
(5) Using Special Tool 8359 Seal Installer install
new oil into oil seal retainer.
(6) Using Special Tool 6687 Guide, install the rear
seal retainer with a new gasket.
(7) Install the timing chain cover with a new gas-
ket and oil seal.
(8) Prime oil pump by squirt oil in the oil filter
mounting hole and filling the J-trap of the front tim-
ing cover. When oil is running out, install oil filter
that has been filled with oil.(9) Apply a rearward axial load of 667 N (150
lbs-f) on crankshaft centerline, driving No.3 main cap
and thrust bearing against No.3 bulkhead. Repeat
procedure, driving crankshaft forward to align rear
flange of thrust bearings in a common plane. Front
face of No.1 main cap must not extend forward in
front of face of No.1 bulkhead.
(10) Install the oil pickup tube. Tighten the bolts
to 16 N´m (144 in. lbs.) torque.
(11) Install the oil pan.
CRANKSHAFT MAIN
BEARINGS
STANDARD PROCEDUREÐFITTING
CRANKSHAFT MAIN BEARINGS
Bearing caps are not interchangeable and should
be marked at removal to ensure correct assembly.
Upper and lower bearing halves are NOT inter-
changeable. All lower main bearing halves are inter-
changeable. Upper main bearing halves of No. 2, 4,
and 5 are interchangeable. Upper main bearing
halves of No. 1 and 6 are interchangeable, this also
applies to the lower bearing halves.
The No.3 main bearing is flanged to carry the
crankshaft thrust loads. This bearing is NOT inter-
changeable with any other bearing halves in the
engine. Bearing shells are available in standard and
the following undersizes: 0.25 mm (0.001 inch), 0.051
mm (0.002 inch), 0.076 mm (0.003 inch), 0.254 mm
(0.010 inch) and 0.305 mm (0.012 inch). Never install
an undersize bearing that will reduce clearance
below specifications.
REMOVAL
(1) Remove the oil pan and oil pump pick-up tube
(Refer to 9 - ENGINE/LUBRICATION/OIL PAN -
REMOVAL).
(2) Identify bearing caps before removal. Remove
bearing caps one at a time.
(3) Remove upper half of bearing by inserting
Crankshaft Main Bearing Remover/Installer Tool
C-3059 into the oil hole of crankshaft (Fig. 30).
(4) 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.
Fig. 29 Main Bearing Identification
1 - MAIN BEARING CAP
2 - UPPER MAIN BEARINGS
3 - CRANKSHAFT
4 - LOWER MAIN BEARINGS
DRENGINE 8.0L 9 - 383
CRANKSHAFT (Continued)

(1) Start bearing in place, and insert Crankshaft
Main Bearing Remover/Installer Tool C-3059 into oil
hole of crankshaft (Fig. 30).
(2) Slowly rotate crankshaft counterclockwise slid-
ing the bearing into position. Remove Tool C-3059.
(3) Lubricate the main journals with clean engine
oil. Install main bearing caps and bolts. Follow the 2
step tightening sequence, starting with No. 1 main
bearing cap.
(4) Apply a rearward axial load of 667 N (150
lbs-f) on crankshaft centerline, driving No.3 main cap
and thrust bearing against No.3 bulkhead. Repeat
procedure, driving crankshaft forward to align rear
flange of thrust bearings in a common plane. Front
face of No.1 main cap must not extend forward in
front of face of No.1 bulkhead.
(5) Install the oil pump pick-up tube and oil pan
(Refer to 9 - ENGINE/LUBRICATION/OIL PAN -
INSTALLATION).
CRANKSHAFT OIL SEAL -
FRONT
REMOVAL
REMOVALÐFRONT OIL SEAL - FRONT COVER
INSTALLED
(1) Disconnect the negative cable from the battery.
(2) Remove vibration damper from the crankshaft
(Refer to 9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - REMOVAL).(3) 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 surface of the cover (Fig.
31).
REMOVALÐFRONT OIL SEAL - FRONT COVER
REMOVED
(1) Remove engine front cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(2) 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 surface of the cover.
INSTALLATION
INSTALLATIONÐFRONT OIL SEAL ± FRONT
COVER INSTALLED
(1) Position the crankshaft front oil seal onto seal
installer special tool 6806 and C-3688 (Fig. 32).
Install seal.
(2) Install vibration damper (Refer to 9 - ENGINE/
ENGINE BLOCK/VIBRATION DAMPER - INSTAL-
LATION).
(3) Install serpentine belt (Refer to 7 - COOLING/
ACCESSORY DRIVE/DRIVE BELTS - INSTALLA-
TION).
(4) Install cooling fan and shroud (Refer to 7 -
COOLING/ENGINE/RADIATOR FAN - INSTALLA-
TION).
(5) Connect negative cable to the battery.
(6) Start engine and check for leaks.
INSTALLATIONÐFRONT OIL SEAL - FRONT
COVER REMOVED
(1) Position the crankshaft front oil seal onto seal
installer special tool 6806.
Fig. 30 Upper Main Bearing Removal and
Installation with Tool C-3059
1 - SPECIAL TOOL C-3059
2 - BEARING
3 - SPECIAL TOOL C-3059
4 - BEARINGFig. 31 Timing Chain Cover and Oil Seal
1 - TIMING CHAIN COVER
2 - OIL SEAL
9 - 384 ENGINE 8.0LDR
CRANKSHAFT MAIN BEARINGS (Continued)

(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. 35).
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) Disconnect the negative cable from the battery.
(2) Remove the air cleaner.
(3) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(4) Remove rocker arm assembly and push rods
(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - REMOVAL). Identify
push rods to ensure installation in original location.
(5) Remove upper and lower intake manifold
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - REMOVAL).(6) Cut the cylinder head gasket for accessibility if
the end tappets are to be removed.
(7) Remove yoke retainer spider and tappet align-
ing yokes (Fig. 36).
Fig. 35 Leak-Down Tester
1 - POINTER
2 - WEIGHTED ARM
3 - RAM
4 - CUP
5 - HANDLE
6 - PUSH ROD
Fig. 36 Tappets, Aligning Yoke and Yoke Retaining
Spider
1 - TAPPET ALIGNING YOLK
2 - YOKE RETAINING SPIDER
3 - TAPPET
DRENGINE 8.0L 9 - 387
HYDRAULIC LIFTERS (Continued)

OIL FILTER
REMOVAL
All engines are equipped with a high quality full-
flow, disposable type oil filter. DaimlerChrysler Cor-
poration 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 (Fig. 51).
(4) When filter separates from adapter nipple, tip
gasket end upward to minimize oil spill. Remove fil-
ter from vehicle.
(5) With a wiping cloth, clean the gasket sealing
surface (Fig. 52) of oil and grime.
(6) Install new filter (Refer to 9 - ENGINE/LUBRI-
CATION/OIL FILTER - INSTALLATION).
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. 52) hand
tighten filter one full turn, do not over tighten.
(3) Add oil (Refer to 9 - ENGINE/LUBRICATION/
OIL - STANDARD PROCEDURE).
OIL PAN
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Raise vehicle.
(3) Drain engine oil.
(4) Remove left engine to transmission strut.
(5) Remove oil pan mounting bolts, pan and one-
piece gasket. The engine may have to be raised
slightly on 2WD vehicles.(6) Remove the oil pick-up tube assembly (Fig. 53).
Discard the gasket.
CLEANING
Clean the block and pan gasket surfaces.
If present, trim excess sealant from inside the
engine.
Clean oil pan in solvent and wipe dry with a clean
cloth.
Clean oil screen and pipe thoroughly in clean sol-
vent. Inspect condition of screen.
INSPECTION
Inspect oil drain plug and plug hole for stripped or
damaged threads. Repair as necessary.
Inspect oil pan mounting flange for bends or distor-
tion. Straighten flange, if necessary.
Fig. 51 Oil Filter RemovalÐTypical
1 - ENGINE OIL FILTER
2 - OIL FILTER WRENCH
Fig. 52 Oil Filter Sealing SurfaceÐTypical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTER
Fig. 53 Oil Pick-Up Tube
1 - PICKÐUP TUBE
2 - SEALANT AT SPLIT-LINES
3 - SEALANT AT SPLIT-LINE
DRENGINE 8.0L 9 - 397

(2) Install and tighten two mounting bolts (screws)
to 7 N´m (60 in. lbs.) torque.
(3) Install electrical connector.
(4) Install air resonator to throttle body.
5.7L V-8
The IAC motor is not serviceable on the 5.7L V-8
engine.
5.9L V-8
The IAC motor is located on the back of the throt-
tle body (Fig. 22).
(1) Install IAC motor to throttle body.
(2) Install and tighten two mounting bolts (screws)
to 7 N´m (60 in. lbs.) torque.
(3) Install electrical connector.
(4) Install air resonator to throttle body.
8.0L V-10
The IAC motor is located on the back of the throt-
tle body (Fig. 23).
(1) Install IAC motor to throttle body.
(2) Install and tighten two mounting bolts (screws)
to 7 N´m (60 in. lbs.) torque.
(3) Install electrical connector.
(4) Install air cleaner housing to throttle body.
(5) Install 4 air cleaner housing mounting nuts.
Tighten nuts to 11 N´m (96 in. lbs.) torque.
(6) Install air cleaner housing cover.
INTAKE AIR TEMPERATURE
SENSOR
DESCRIPTION
The 2±wire Intake Manifold Air Temperature (IAT)
sensor is installed in the intake manifold with the
sensor element extending into the air stream.
The IAT sensor is a two-wire Negative Thermal
Coefficient (NTC) sensor. Meaning, as intake mani-
fold temperature increases, resistance (voltage) in the
sensor decreases. As temperature decreases, resis-
tance (voltage) in the sensor increases.
OPERATION
The IAT sensor provides an input voltage to the
Powertrain Control Module (PCM) indicating the
density of the air entering the intake manifold based
upon intake manifold temperature. At key-on, a
5±volt power circuit is supplied to the sensor from
the PCM. The sensor is grounded at the PCM
through a low-noise, sensor-return circuit.
The PCM uses this input to calculate the following:
²Injector pulse-width²Adjustment of spark timing (to help prevent
spark knock with high intake manifold air-charge
temperatures)
The resistance values of the IAT sensor is the same
as for the Engine Coolant Temperature (ECT) sensor.
REMOVAL
3.7L V-6
The intake manifold air temperature (IAT) sensor
is installed into the left side of intake manifold ple-
num (Fig. 24).
(1) Disconnect electrical connector from IAT sen-
sor.
(2) Clean dirt from intake manifold at sensor base.
(3) Gently lift on small plastic release tab (Fig. 24)
or (Fig. 25) and rotate sensor about 1/4 turn counter-
clockwise for removal.
(4) Check condition of sensor o-ring.
4.7L V-8
The intake manifold air temperature (IAT) sensor
is installed into the left side of intake manifold ple-
num (Fig. 26).
(1) Disconnect electrical connector from IAT sen-
sor.
(2) Clean dirt from intake manifold at sensor base.
(3) Gently lift on small plastic release tab (Fig. 25)
or (Fig. 26) and rotate sensor about 1/4 turn counter-
clockwise for removal.
Fig. 24 IAT SENSOR LOCATION - 3.7L V-6
1 - IAT SENSOR
2 - RELEASE TAB
3 - ELECTRICAL CONNECTOR
14 - 36 FUEL INJECTION - GASDR
IDLE AIR CONTROL MOTOR (Continued)