
The relief valve spring has a free length of approx-
imately 49.5 mm (1.95 inches). The spring should
test between 19.5 and 20.5 pounds when compressed
to 34 mm (1-11/32 inches). Replace spring that fails
to meet these specifications (Fig. 66).
If oil pressure was low and pump is within specifi-
cations, inspect for worn engine bearings or other
reasons for oil pressure loss.
ASSEMBLY
(1) Install pump rotors and shaft, using new parts
as required.
(2) Position the oil pump cover onto the pump
body. Tighten cover bolts to 11 N´m (95 in. lbs.)
torque.
(3) Install the relief valve and spring. Insert the
cotter pin.
(4) Tap on a new retainer cap.
(5) Prime oil pump before installation by filling
rotor cavity with engine oil.
INSTALLATION
(1) Install oil pump. During installation slowly
rotate pump body to ensure driveshaft-to-pump rotor
shaft engagement.
(2) Hold the oil pump base flush against mating
surface on No.5 main bearing cap. Finger tighten
pump attaching bolts. Tighten attaching bolts to 41
N´m (30 ft. lbs.) torque.
(3) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
INTAKE MANIFOLD
DESCRIPTION
The aluminum intake manifold (Fig. 67) is a single
plane design with equal length runners and uses a
separate plenum, therefore the manifold does have a
plenum gasket. It also uses separate flange gaskets
and front and rear cross-over gaskets. Extreme care
must be used when sealing the gaskets to ensure
that excess sealant does not enter the intake runners
causing a restriction. Whenever the intake manifold
is removed inspect the plenum pan for evidence of
excess oil buildup, this condition indicates that the
plenum pan gasket is leaking.
OPERATION
The intake manifold, meters and delivers air to the
combustion chambers allowing the fuel delivered by
the fuel injectors to ignite, thus producing power.
DIAGNOSIS AND TESTINGÐINTAKE
MANIFOLD LEAKAGE
An intake manifold air leak is characterized by
lower than normal manifold vacuum. Also, one or
more cylinders may not be functioning.
Fig. 66 Proper Installation of Retainer Cap
1 - RETAINER CAP
2 - CHAMFER
3 - COTTER KEY
Fig. 67 Intake Manifold and Throttle BodyÐV-8 Gas
Engines Typical
1 - FUEL RAIL ASSEMBLY
2 - FUEL RAIL MOUNTING BOLTS
3 - FUEL RAIL CONNECTING HOSES
9 - 274 ENGINE - 5.9LDR
OIL PUMP (Continued)

(5)Install the front and rear end seals (Fig. 70) Make
sure the molded dowel pins on the end seals fully enter the
corresponding holes in the cylinder block.
(6)Carefully lower intake manifold into position on
the cylinder block and cylinder heads. After intake man-
ifold is in place, inspect to make sure seals are in place.
(7) Using a new gasket, install the throttle body
onto the intake manifold. Tighten the bolts to 23 N´m
(200 in. lbs.) torque.(8) Install the intake manifold bolts and tighten as
follows (Fig. 72):
²Step 1. Tighten bolts 1 through 4 to 8 N´m (72
in. lbs.) Tighten in alternating steps 1.4 N´m (12 in.
lbs.) at a time
²Step 2. Tighten bolts 5 through 12 to 8 N´m (72
in. lbs.)
²Step 3. Check all bolts are torqued to 8 N´m (72
in. lbs.)
²Step 4. Tighten all bolts in sequence to 16 N´m
(12 ft. lbs.)
²Step 5. Check all bolts are torqued to 16 N´m
(12 ft. lbs.)
(9) Install closed crankcase ventilation and evapo-
ration control systems.
(10) Connect the coil wires.
(11) Connect the heat indicator sending unit wire.
(12) Connect the heater hoses and bypass hose.
(13) Install distributor cap and wires.
(14) Hook up the return spring.
(15) Connect the accelerator linkage (Refer to 14 -
FUEL SYSTEM/FUEL INJECTION/THROTTLE
CONTROL CABLE - INSTALLATION) and if so
Fig. 69 Plenum Pan Bolt Tightening Sequence
Fig. 70 Front and Rear End Seals
1 - FRONT CROSS-OVER GASKET
2 - REAR CROSS-OVER GASKET
Fig. 71 Intake Manifold Flange Gasket Alignment
1 - FLANGE GASKET
2 - ALIGNMENT TABS
3 - CYLINDER HEAD GASKET
9 - 276 ENGINE - 5.9LDR
INTAKE MANIFOLD (Continued)

equipped, the speed control and transmission kick-
down cables.
(16) Install the fuel lines (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE).
(17) Install the accessory drive bracket and A/C
compressor (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/A/C COMPRESSOR -
INSTALLATION).
(18) Install the generator and drive belt (Refer to 7
- COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION). Tighten generator mounting bolt
to 41 N´m (30 ft. lbs.) torque.
(19) Install the air cleaner.
(20) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(21) Connect the negative cable to the battery.
EXHAUST MANIFOLD
DESCRIPTION
The exhaust manifolds (Fig. 73) are constructed of
cast iron and are LOG type with balanced flow. One
exhaust manifold is attached to each cylinder head.
OPERATION
The exhaust manifolds collect the engine exhaust
exiting the combustion chambers, then channels the
exhaust gases to the exhaust pipes attached to the
manifolds.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Raise and support the vehicle.
(3) Remove the bolts and nuts attaching the
exhaust pipe to the engine exhaust manifold.
(4) Lower the vehicle.
(5) Remove the exhaust heat shields.(6) Remove bolts, nuts and washers attaching
manifold to cylinder head.
(7) Remove manifold from the cylinder head.
CLEANING
Clean mating surfaces on cylinder head and mani-
fold. Wash with solvent and blow dry with com-
pressed air.
INSPECTION
Inspect manifold for cracks.
Inspect mating surfaces of manifold for flatness
with a straight edge. Gasket surfaces must be flat
within 0.2 mm per 300 mm (0.008 inch per foot).
INSTALLATION
CAUTION: If the studs came out with the nuts when
removing the engine exhaust manifold, install new
studs. Apply sealer on the coarse thread ends.
Water leaks may develop at the studs if this precau-
tion is not taken.
(1) Position the engine exhaust manifolds on the
two studs located on the cylinder head. Install coni-
cal washers and nuts on these studs (Fig. 74).
(2) Install two bolts and conical washers at the
inner ends of the engine exhaust manifold outboard
arms. Install two bolts WITHOUT washers on the
center arm of engine exhaust manifold (Fig. 74).
Starting at the center arm and working outward,
tighten the bolts and nuts to 34 N´m (25 ft. lbs.)
torque.
(3) Install the exhaust heat shields.
(4) Raise and support the vehicle.
Fig. 72 Intake Manifold Bolt Tightening SequenceFig. 73 Exhaust ManifoldsÐV-8 Gas Engines Typical
1 - EXHAUST MANIFOLD (LEFT)
2 - BOLTS & WASHERS
3 - NUTS & WASHERS
4 - EXHAUST MANIFOLD (RIGHT)
5 - BOLTS & WASHERS
DRENGINE - 5.9L 9 - 277
INTAKE MANIFOLD (Continued)

(5) Assemble exhaust pipe to manifold and secure
with bolts, nuts and retainers. Tighten the bolts and
nuts to 34 N´m (25 ft. lbs.) torque.
(6) Lower the vehicle.
(7) Connect the negative cable to the battery.
TIMING BELT / CHAIN
COVER(S)
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Remove water pump (Refer to 7 - COOLING/
ENGINE/WATER PUMP - REMOVAL).
(3) Remove power steering pump (Refer to 19 -
STEERING/PUMP - REMOVAL).
(4) Remove vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(5) Loosen oil pan bolts and remove the front bolt
at each side.
(6) Remove the cover bolts.
(7) Remove chain case cover and gasket using
extreme caution to avoid damaging oil pan gasket.
INSTALLATION
(1) Be sure mating surfaces of chain case cover
and cylinder block are clean and free from burrs.
(2) The water pump mounting surface must be
cleaned.
(3) Using a new cover gasket, carefully install
chain case cover to avoid damaging oil pan gasket.
Use a small amount of MopartSilicone Rubber Adhe-
sive Sealant, or equivalent, at the joint between tim-
ing chain cover gasket and the oil pan gasket. Finger
tighten the timing chain cover bolts at this time.NOTE: Special Tool 6635 must be used to align the
front cover and seal with the crankshaft.
(4) Position the special tool 6635 onto the crank-
shaft (Fig. 75).
(5) Tighten chain case cover bolts to 41 N´m (30
ft.lbs.) torque. Tighten oil pan bolts to 24 N´m (215
in. lbs.) torque.
(6) Remove special tool 6635.
(7)
Inspect the seal flange on the vibration damper.
(8) Install vibration damper (Refer to 9 - ENGINE/
ENGINE BLOCK/VIBRATION DAMPER - INSTAL-
LATION).
(9) Install water pump and housing assembly
using new gaskets (Refer to 7 - COOLING/ENGINE/
WATER PUMP - INSTALLATION).
(10) Install power steering pump (Refer to 19 -
STEERING/PUMP - INSTALLATION).
(11) Install the serpentine belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).
(12) Install the cooling system fan (Refer to 7 -
COOLING/ENGINE/RADIATOR FAN - INSTALLA-
TION).
(13) Position the fan shroud and install the bolts.
Tighten the bolts to 11 N´m (95 in. lbs.) torque.
(14) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(15) Connect the negative cable to the battery.
(16) Start engine check for leaks.
Fig. 74 Engine Exhaust Manifold Installation - 5.9L
Engines
1 - EXHAUST MANIFOLD (LEFT)
2 - BOLTS & WASHERS
3 - NUTS & WASHERS
4 - EXHAUST MANIFOLD (RIGHT)
5 - BOLTS & WASHERS
Fig. 75 Position Special Tool 6635 onto Crankshaft
1 - SPECIAL TOOL 6635
2 - OIL SEAL
3 - TIMING CHAIN COVER
9 - 278 ENGINE - 5.9LDR
EXHAUST MANIFOLD (Continued)

TIMING BELT/CHAIN AND
SPROCKETS
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove Timing Chain Cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(3) Re-install the vibration damper bolt finger
tight. Using a suitable socket and breaker bar, rotate
the crankshaft to align timing marks as shown in
(Fig. 76).
(4) Remove camshaft sprocket attaching bolt and
remove timing chain with crankshaft and camshaft
sprockets.
INSPECTIONÐMEASURING TIMING CHAIN
STRETCH
(1) Place a scale next to the timing chain so that
any movement of the chain may be measured.
(2) Place a torque wrench and socket over cam-
shaft sprocket attaching bolt. Apply torque in the
direction of crankshaft rotation to take up slack; 41
N´m (30 ft. lbs.) torque with cylinder head installed
or 20 N´m (15 ft. lbs.) torque with cylinder head
removed. With a torque applied to the camshaft
sprocket bolt, crankshaft should not be permitted to
move. It may be necessary to block the crankshaft to
prevent rotation.
(3) Hold a scale with dimensional reading even
with the edge of a chain link. With cylinder heads
installed, apply 14 N´m (30 ft. lbs.) torque in the
reverse direction. With the cylinder heads removed,
apply 20 N´m (15 ft. lbs.) torque in the reverse direc-
tion. Note the amount of chain movement (Fig. 77).
(4) Install a new timing chain, if its movement
exceeds 3.175 mm (1/8 inch).
INSTALLATION
(1) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on exactimaginary center line through both camshaft and
crankshaft bores.
(2) Place timing chain around both sprockets.
(3) Turn crankshaft and camshaft to line up with
keyway location in crankshaft sprocket and in cam-
shaft sprocket.
(4) Lift sprockets and chain (keep sprockets tight
against the chain in position as described).
(5) Slide both sprockets evenly over their respec-
tive shafts and use a straightedge to check alignment
of timing marks (Fig. 78).
(6) Install the camshaft bolt. Tighten the bolt to 68
N´m (50 ft. lbs.) torque.
(7) Check camshaft end play. The end play should
be 0.051-0.152 mm (0.002-0.006 inch) with a new
thrust plate and up to 0.254 mm (0.010 inch) with a
used thrust plate. If not within these limits install a
new thrust plate.
(8) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
Fig. 76 Alignment of Timing Marks
1 - TIMING MARKS
Fig. 77 Measuring Timing Chain Stretch
1 - TORQUE WRENCH
2 - 3.175 MM
(0.125 IN.)
Fig. 78 Alignment of Timing Marks
1 - TIMING MARKS
DRENGINE - 5.9L 9 - 279

ENGINE 5.9L DIESEL
TABLE OF CONTENTS
page page
ENGINE 5.9L DIESEL
DESCRIPTION........................282
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - MECHANICAL............283
DIAGNOSIS AND TESTINGÐSMOKE
DIAGNOSIS CHARTS.................285
DIAGNOSIS AND TESTINGÐCYLINDER
COMPRESSION/LEAKAGE TESTS.......288
STANDARD PROCEDURE
STANDARD PROCEDURE - FORM-IN-
PLACE GASKETS AND SEALERS........289
STANDARD PROCEDURE - REPAIR
DAMAGED OR WORN THREADS........289
STANDARD PROCEDUREÐHYDROSTATIC
LOCK..............................290
REMOVAL
REMOVALÐENGINE..................290
REMOVALÐCRANKCASE BREATHER....291
INSTALLATION
INSTALLATIONÐENGINE..............291
INSTALLATIONÐCRANKCASE BREATHER . 292
SPECIFICATIONS
5.9L DIESEL........................293
TORQUE...........................294
SPECIAL TOOLS
5.9L DIESEL ENGINE.................294
ENGINE DATA PLATE
DESCRIPTION........................297
AIR CLEANER ELEMENT
REMOVAL............................297
INSTALLATION........................298
CYLINDER HEAD
DESCRIPTION........................298
REMOVAL............................298
CLEANING
CLEANINGÐCYLINDER HEAD..........300
CLEANINGÐCROSSHEADS............300
CLEANINGÐPUSHRODS..............301
INSPECTION
INSPECTION - CYLINDER HEAD.........301
INSPECTIONÐCROSSHEADS..........301
INSPECTIONÐPUSHRODS.............302
INSTALLATION........................302
CYLINDER HEAD COVER(S)
REMOVAL
REMOVALÐCYLINDER HEAD COVER....304
REMOVALÐROCKER HOUSING.........304
CLEANING...........................304INSPECTION.........................304
INSTALLATION
INSTALLATIONÐCYLINDER HEAD COVER . 304
INSTALLATIONÐROCKER HOUSING.....304
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION........................305
STANDARD PROCEDURE
STANDARD PROCEDURE - VALVES,
GUIDES AND SPRINGS................305
STANDARD PROCEDURE - VALVE LASH
ADJUSTMENT AND VERIFICATION.......308
REMOVAL - VALVE SPRINGS AND SEALS . . . 308
INSTALLATION........................309
ROCKER ARM / ADJUSTER ASSY
DESCRIPTION........................310
REMOVAL............................310
CLEANING...........................310
INSPECTION..........................311
INSTALLATION........................312
ENGINE BLOCK
STANDARD PROCEDURE
STANDARD PROCEDURE - CYLINDER
BLOCK REFACING...................312
STANDARD PROCEDURE - CYLINDER
BORE - DE-GLAZE...................313
STANDARD PROCEDUREÐCYLINDER
BORE REPAIR.......................313
STANDARD PROCEDUREÐCAM BORE
REPAIR ............................315
INSPECTION.........................316
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL
REMOVALÐCAMSHAFT BEARINGS......317
REMOVAL - CAMSHAFT...............317
INSPECTION.........................318
INSTALLATION
INSTALLATION - CAMSHAFT BEARINGS . . 320
INSTALLATION - CAMSHAFT............320
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING
ROD BEARING AND CRANKSHAFT
JOURNAL CLEARANCE................321
CRANKSHAFT AND GEAR
DESCRIPTION........................322
REMOVALÐGEAR.....................322
INSTALLATION - GEAR..................322
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDURE - MAIN BEARING
CLEARANCE........................322
9 - 280 ENGINE 5.9L DIESELDR

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTINGÐENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTION
LUBRICATING OIL
PRESSURE LOW1. Low oil level. 1. (a) Check and fill with clean engine oil.
(b) Check for a severe external oil leak that
could reduce the pressure.
2. Oil viscosity thin, diluted or wrong
specification.2. (a) Verify the correct engine oil is being
used. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
2. (b) Look for reduced viscosity from fuel
dilution.
3. Improperly operating pressure
switch/gauge.3. Verify the pressure switch is functioning
correctly. If not, replace switch/gauge.
4. Relief valve stuck open. 4. Check/replace valve.
6. If cooler was replaced, shipping
plugs may have been left in cooler6. Check/remove shipping plugs.
7. Worn oil pump. 7. Check and replace oil pump.
8. Suction tube loose or seal leaking. 8. Check and replace seal.
9. Loose main bearing cap. 9. Check and install new bearing. Tighten
cap to proper torque.
10. Worn bearings or wrong bearings
installed.10. Inspect and replace connecting rod or
main bearings. Check and replace directed
piston cooling nozzles.
11. Directed piston cooling nozzles
under piston, bad fit into main
carrier.11. Check directed piston cooling nozzles
position.
12. Loose oil rifle plug with saddle-jet
style nozzles12.Tighten oil rifle plug.
13. Loose directed piston cooling
nozzle.13. Tighten directed piston cooling nozzle.
14. Both J-jet and saddle jet style
cooling nozzle installed.14. Install correct style jet.
LUBRICATING OIL
PRESSURE TOO HIGH1. Pressure switch/gauge not
operating properly.1. Verify pressure switch is functioning
correctly. If not, replace switch/gauge.
2. Engine running too cold. 2. Refer to Coolant Temperature Below
Normal (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
3. Oil viscosity too thick. 3. Make sure the correct oil is being used.
(Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
4. Oil pressure relief valve stuck
closed or binding4. Check and replace valve.
DRENGINE 5.9L DIESEL 9 - 283
ENGINE 5.9L DIESEL (Continued)

EXCESSIVE BLACK SMOKE
POSSIBLE CAUSE CORRECTION
Manifold Air Pressure (Boost) Sensor or sensor circuit
malfunctioning.A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Raw fuel in intake manifold. Fuel injectors leaking on engine shutdown. Do Fuel
Injector Test (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/FUEL INJECTOR - DIAGNOSIS AND
TESTING).
Turbocharger air intake restriction. Remove restriction.
Turbocharger damaged. (Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - INSPECTION).
Turbocharger has excess build up on compressor
wheel and/or diffuser vanes.(Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - CLEANING).
Turbocharger wheel clearance out of specification. (Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - INSPECTION).
EXCESSIVE WHITE SMOKE
POSSIBLE CAUSE CORRECTION
Air in fuel supply: Possible leak in fuel supply side
(between transfer pump and fuel tank module).(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/FUEL
TRANSFER PUMP - DIAGNOSIS AND TESTING).
Coolant leaking into combustion chamber. Do pressure test of cooling system (Refer to 7 -
COOLING - DIAGNOSIS AND TESTING).
Diagnostic Trouble Codes (DTC's) active or multiple,
intermittent DTC's.Refer to Powertrain Diagnostic Procedures Information.
In very cold ambient temperatures, engine block heater
is malfunctioning (if equipped).(Refer to 7 - COOLING/ENGINE/ENGINE BLOCK
HEATER - REMOVAL).
Engine coolant temperature sensor malfunctioning. A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information. Also check
thermostat operation (Refer to 7 - COOLING/ENGINE/
ENGINE COOLANT THERMOSTAT - DIAGNOSIS AND
TESTING).
Engine Control Module (ECM) not calibrated or has
incorrect calibration.A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Fuel filter plugged. Refer to Powertrain Diagnostic Manual for fuel system
testing.
Fuel grade not correct or fuel quality is poor. Temporarily change fuel brands and note condition.
Change brand if necessary.
Fuel heater element or fuel heater temperature sensor
malfunctioning. This will cause wax type build-up in fuel
filter.Refer to Fuel Heater Testing (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL HEATER -
DIAGNOSIS AND TESTING).
Fuel injector malfunctioning. A DTC should have been set. Perform9Cylinder cutout
Test9using DRB scan tool to isolate individual
cylinders. Also refer to Powertrain Diagnostic
Procedures Information and, (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
DIAGNOSIS AND TESTING).
Fuel injector hold-downs loose. Torque to specifications.
9 - 286 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)