
Filter Removal
(1) The housing cover is equipped with spring clips
(Fig. 6) and is hinged with plastic tabs. Unlatch clips
from top of air cleaner housing and tilt housing cover
up for cover removal.
(2) Remove air cleaner element from air cleaner
housing.
INSTALLATION
(1) Before installing new air cleaner element (fil-
ter), clean inside of air cleaner housing.
(2) Position air cleaner cover to tabs on front of air
cleaner housing. Latch spring clips to seal cover to
housing.
CYLINDER HEAD
DESCRIPTION
The cylinder head is constructed of cast iron and is
a one piece cross flow design with four valves per cyl-
inder. The arrangement of two intake and two
exhaust valves per cylinder allows for a centrally
located injector. The cylinder head also includes an
integral intake manifold, an integral thermostat
housing, and a longitudal fuel return rifle, which
exits at the rear of the head. The 24 valve design
also includes integrally cast valve guides and hard-
ened intake and exhaust valve seat inserts.
REMOVAL
(1) Disconnect battery negative cables.
(2) Raise vehicle on hoist.
(3) Drain engine coolant.
(4) Disconnect exhaust pipe from turbocharger
elbow.
(5) Disconnect turbocharger oil drain tube at rub-
ber hose connection. Cap off open ports to prevent
intrusion of dirt or foreign material.
(6) Lower vehicle.
(7) Disconnect air inlet temperature/pressure sen-
sor.
(8) Remove air cleaner housing and snorkel from
the vehicle. Cap off turbocharger air inlet to prevent
intrusion of dirt or foreign material.
(9) Disconnect cab heater core supply and return
hoses from the cylinder head and heater pipe.
(10) Disconnect turbocharger oil supply line at the
turbocharger end. Cap off open ports to prevent
intrusion of dirt or foreign material.
(11) Remove exhaust manifold-to-cylinder head
bolts, spacers, heat shield, retention straps, and cab
heater plumbing. Remove exhaust manifold and tur-
bocharger from the vehicle as an assembly.
(12) Remove cooling fan assembly.
(13) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(14) Remove cooling fan support from cylinder
block.
(15) Remove upper generator bolt, loosen lower
generator bolt, and rotate generator away from cylin-
der head.
(16) Disconnect radiator upper hose from the ther-
mostat housing.
(17) Disconnect the Intake Air Temperature/Mani-
fold Air Pressure, and Coolant Temperature sensor
connectors.
(18) Remove the engine harness to cylinder head
attaching bolts and P-clips at front of head.
(19) Remove the throttle linkage cover (Fig. 8).
(20) For automatic equipped vehicles only, remove
the six (6) accelerator pedal position sensor assem-
bly-to-cylinder head bracket bolts (Fig. 9) and secure
the entire assembly out of the way. Disconnect the
APPS connector (Fig. 10).It is not necessary to
disconnect the cables from the throttle control
assembly.
(21) Remove the intake air grid heater wires from
the grid heater.
(22) Remove engine oil level indicator tube attach-
ing bolt at fuel filter housing bracket and inlet air
connection..
(23) Remove the charge air cooler-to-air inlet hous-
ing pipe.
Fig. 7 FILTER MINDERŸ - 5.9L DIESEL
1 - PRESS BUTTON TO RESET
2 - YELLOW DISC
3 - RED ZONE
4 - TO AIR FILTER HOUSING
5 - FILTER MINDER
DRENGINE 5.9L DIESEL 9 - 249
AIR CLEANER ELEMENT (Continued)

(32) Disconnect fuel heater, water in fuel sensor,
and fuel lift pump connectors.
(33) Remove the fuel filter assembly-to-cylinder
head bolts and remove filter assembly from vehicle.
(34) Remove wire harness P-clip from cylinder
head (located behind filter housing).
(35) Remove the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(36) Disconnect rocker housing injector harness
connectors.
(37) Remove injector harness nuts from injectors.
(38) Remove the rocker levers (Fig. 11), cross
heads and push rods (Fig. 12). Mark each component
so they can be installed in their original positions.
NOTE: The #5 cylinder exhaust and the #6 cylinder
intake and exhaust push rods are removed by lift-
ing them up and through the provided cowl panel
access holes. Remove the rubber plugs to expose
these relief holes.
(39) Remove the fuel return line and banjo bolt at
the rear of the cylinder head. Be careful not to drop
the two (2) sealing washers.
(40) Remove the fuel injectors (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
REMOVAL).
(41) Remove rocker housing bolts and rocker hous-
ing and gasket.(42) Reinstall the engine lift bracket at the rear of
cylinder head. Torque to 77 N´m (57 ft. lbs.).
(43) Remove twenty six (26) cylinder head-to-block
bolts.
(44) Attach an engine lift crane to engine lift
brackets and lift cylinder head off engine and out of
vehicle.
(45) Remove the head gasket and inspect for fail-
ure.
CLEANING
CLEANINGÐCYLINDER HEAD
CAUTION: Do not wire brush head surface while
fuel injectors are still installed. Fuel injector dam-
age can result.
Remove fuel injector before cleaning (if not already
removed during cylinder head removal).
Clean the carbon from the injector nozzle seat with
a nylon or brass brush.
Scrape the gasket residue from all gasket surfaces.
Wash the cylinder head in hot soapy water solution
(88ÉC or 140ÉF).
After rinsing, use compressed air to dry the cylin-
der head.
Polish the gasket surface with 400 grit paper. Use
an orbital sander or sanding block to maintain a flat
surface.
CLEANINGÐCROSSHEADS
Clean all crossheads in a suitable solvent. If neces-
sary, use a wire brush or wheel to remove stubborn
deposits. Rinse in hot water and blow dry with com-
pressed air.
Fig. 11 Rocker Arm and Pedestal Removal
1 - ROCKER ARM
2 - PEDESTAL
Fig. 12 Push Rod Removal
DRENGINE 5.9L DIESEL 9 - 251
CYLINDER HEAD (Continued)

CLEANINGÐPUSHRODS
Clean the pushrods in a suitable solvent. Rinse in
hot water and blow dry with compressed air. If nec-
essary, use a wire brush or wheel to remove stubborn
deposits.
INSPECTION
INSPECTION - CYLINDER HEAD
Inspect the cylinder head for cracks in the combus-
tion surface. Pressure test any cylinder head that is
visibly cracked. A cylinder head that is cracked
between the injector bore and valve seat can be pres-
sure tested and reused if OK; however, if the crack
extendsintothe valve seat insert bore, the cylinder
headmustbe replaced.
Visually inspect the cylinder block and head com-
bustion surfaces for localized dips or imperfections.
Check the cylinder head and block combustion sur-
faces for overall out-of-flatness. If either the visual or
manual inspection exceeds the limits, then the head
or block must be surfaced.
Check the top surface for damage caused by the
cylinder head gasket leaking between cylinders.
Inspect the block and head surface for nicks, ero-
sion, etc.
Check the head distortion. Maximum overall vari-
ation end to end is 0.305 mm (0.012 inch) (Fig. 13),
and maximum overall variation side to side 0.076
mm ( .003 in.).
DO NOT proceed with the in-chassis overhaul if
the cylinder head or block surface is damaged or not
flat (within specifications).
Check block surface for distortion. Maximum vari-
ation end-to-end is 0.076 mm ( .003 in.), side-to-side
0.051 mm (.002).Visually inspect the cylinder head bolts for dam-
aged threads, corroded/pitted surfaces, or a reduced
diameter due to bolt stretching.
If the bolts are not damaged, their ªfree lengthº
should be measured using the cap screw stretch
gauge provided with the replacement head gasket.
Place the head of the bolt against the base of the slot
and align the bolt with the straight edge of gauge
(Fig. 14). If the end of the bolt touches the foot of the
gauge, the boltmustbe discarded.The maximum
bolt free length is 132.1 mm (5.200 in.).
INSPECTIONÐCROSSHEADS
Inspect the crossheads for cracks and/or excessive
wear on rocker lever and valve tip mating surfaces
(Fig. 15). Replace any crossheads that exhibit abnor-
mal wear or cracks.
Fig. 13 Cylinder Head Combustion Deck Face
1 - STRAIGHT EDGE
2 - FEELER GAUGE
Fig. 14 Head Bolt Stretch Gauge
Fig. 15 Inspecting Crosshead for Cracks
9 - 252 ENGINE 5.9L DIESELDR
CYLINDER HEAD (Continued)

INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves are made of heat resistant steel, and
have chrome plated stems to prevent scuffing. The
intake and exhaust valves are both similar in head
diameter and overall length, but they have unique
face angles which makes them non-interchangeable.
The valves are distinguished by unique dimples on
the exhaust valve head (Fig. 21).
The exhaust valve springs are made from high
strength, chrome silicon steel. The exhaust valve
springs are also exhaust brake compatible.
STANDARD PROCEDURE
STANDARD PROCEDURE - VALVES, GUIDES
AND SPRINGS
REMOVAL
(1) Remove cylinder head (Refer to 9 - ENGINE/
CYLINDER HEAD - REMOVAL).
(2) Support cylinder head on stands, or install
head bolts upside down (through combustion surface
side) to protect injector tips from damage from work
bench.
(3) Install the valve spring compressor mounting
base as shown in (Fig. 22).
(4) Install the compressor top plate, washer, and
nut. Using a suitable wrench, tighten the nut (clock-
wise) to compress the valve springs (Fig. 23) and
remove the locks.
Fig. 22 Spring Compressor Mounting BaseÐPart of
Tool 8319±A
1 - COMPRESSOR MOUNTING BASE
Fig. 23 Compressing Valve Springs with Tool
8319±A
1 - SPECIAL TOOL 8319
Fig. 21 Valve Identification
1 - INTAKE VALVES
2 - EXHAUST VALVES
9 - 256 ENGINE 5.9L DIESELDR

(5) Rotate the compressor nut counter-clockwise to
relieve tension on the springs. Remove the spring
compressor.
(6) Remove the retainers, springs, valve seals (if
necessary), and valves (Fig. 24). Arrange or number
all components so they can be installed in their orig-
inal locations.
(7) Repeat the procedure on all cylinders to be ser-
viced.
CLEANING
Clean the valve stems with crocus cloth or a
Scotch-BriteŸ pad. Remove carbon with a soft wire
brush. Clean valves, springs, retainers, and valve
retaining locks in a suitable solvent. Rinse in hot
water and blow dry with compressed air.
INSPECTION
Visually inspect the valves for abnormal wear on
the heads, stems, and tips. Replace any valve that is
worn out or bent (Fig. 25).
Measure the valve stem diameter in three places
as shown in (Fig. 26).
Measure the cylinder head valve guide bore (Fig.
27).
VALVE GUIDE BORE SPECIFICATIONS
VALVE GUIDE BORE SPECIFICATIONS
Valve guide bore
diameter
Min. 7.027 mm (0.2767 in.)
Max. 7.077 mm (0.2786 in.)
Installed valve guide
depth
Intake
Min. 0.584 mm ( 0.023 in.)
Max. 1.092 mm ( 0.043 in.)
Exhaust
Min. 0.965 mm ( 0.028 in.)
Max. 1.473 mm (0.058 in.)
Fig. 24 Valve Spring, Seal, and Retainers
1 - VALVE RETAINING LOCKS
2 - VALVE
3 - SEAL
4 - SPRING
5 - RETAINER
Fig. 25 Visually Inspect Valves for Abnormal Wear
Fig. 26 Measure Valve Stem Diameter
VALVE STEM DIAMETER
6.96 mm (0.2740 in.) MIN
7.010 mm (0.2760 in.) MAX
DRENGINE 5.9L DIESEL 9 - 257
INTAKE/EXHAUST VALVES & SEATS (Continued)

INSTALLATION
(1) Install new valve seals. The yellow seals are for
the intake valves and the green seals are for the
exhaust valves.
(2) Install the valves in their original postion. The
exhaust valves are identified by a dimple on the
valve head (Fig. 31).
(3) Install the valve springs and retainer.
(4) Install the valve spring compressor tool 8319±A
as shown in (Fig. 22) and (Fig. 23).
(5) Compress the valve springs and install the
valve retaining locks (Fig. 24).
(6) Remove the compressor and repeat the proce-
dure on the remaining cylinders.
(7) Install new o-ring and sealing washer on injec-
tor.
(8) Lubricate o-ring and injector bore.
(9) Verify sealing washer (shim) was removed with
old injector.
(10) Install injector Refer to (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
INSTALLATION).
(11) Install the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - INSTALLATION).
STANDARD PROCEDURE - VALVE LASH
ADJUSTMENT AND VERIFICATION
NOTE: To obtain accurate readings, valve lash mea-
surements AND adjustments should only be per-
formed when the engine coolant temperature is less
than 60É C (140É F).
The 24±valve overhead system is a ªlow-mainte-
nanceº design. Routine adjustments are no longer
necessary, however, measurement should still takeplace when trouble-shooting performance problems,
or upon completion of a repair that includes removal
and installation of the valve train components or
injectors.
(1) Disconnect battery negative cables.
(2) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(3) Using the crankshaft barring tool #7471±B,
rotate crankshaft to align damper TDC mark to
12:00 o'clock position.
(a) If both number one cylinder rocker levers are
loose, continue to next step.
(b) If both number one clylinder rocker levers
are not loose, rotate crankshaft 360 degrees.
(4) With the engine in this position, valve lash can
be measured at the following rocker arms:INTAKE
1±2±4 / EXHAUST 1±3±5. Measure the valve lash by
inserting a feeler gauge between the rocker arm
socket and crosshead (Fig. 32). Refer to VALVE
LASH LIMIT CHART for the correct specifications. If
the measurement fallswithinthe limits, adjust-
ment/resettingis notnecessary. If measurement
finds the lashoutsideof the limits, adjustment/re-
settingisrequired.
VALVE LASH LIMIT CHART
INTAKE EXHAUST
0.152 mm ( 0.006 in.)
MIN.0.381 mm (0.015 in.)
MIN.
0.381 mm (0.015 in.)
MAX.0.762 mm (0.030 in.)
MAX.
note:
If measured valve lash falls within these
specifications, no adjustment/reset is necessary.
Engine operation within these ranges has no adverse
affect on performance, emissions, fuel economy or
level of engine noise.
(5) If adjustment/resetting is required, loosen the
lock nut on rocker arms and turn the adjusting screw
until the desired lash is obtained:
²INTAKE0.254 mm (0.010 in.)
²EXHAUST0.508 mm (0.020 in.) Tighten the
lock nut to 24 Nm (18 ft. lbs.) and re-check the valve
lash.
(6) Using the crankshaft barring tool, rotate the
crankshaftone revolution (360É) to align the
damper TDC mark to the 12 o'clock position.
Fig. 31 Valve Identification
1 - INTAKE VALVES
2 - EXHAUST VALVES
DRENGINE 5.9L DIESEL 9 - 259
INTAKE/EXHAUST VALVES & SEATS (Continued)

(7) With the engine in this position, valve lash can
be measured at the remaining rocker arms:INTAKE
3±5±6 / EXHAUST 2±4±6. Use the same method as
above for determining whether adjustment is neces-
sary, and adjust those that are found to be outside of
the limits.
(8) Install the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(9) Connect the battery negative cables.
REMOVAL - VALVE SPRINGS AND SEALS
(1) Disconnect the battery negative cables.
(2) Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(3) Disconnect rocker housing injector harness con-
nector. Remove all injector harness solenoid nuts.
(4) Remove injector(s) for cylinder(s) to be serviced.
Refer to Group 14 for injector removal.
(5) Remove the rocker housing.
(6) Remove the rocker arms and crossheads from
the cylinder(s) to be serviced. Mark each component
so they can be installed in their original position.
(7) Using the crankshaft barring tool #7471±B
(Fig. 33), rotate the engine to position the damper
mark in the 12 o'clock position.At this engine posi-
tion, cylinders #1 and #6 can be serviced.
(8) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(9) With the damper TDC mark in the 12 o'clock
position, add a paint mark anywhere on the gear
housing cover next to the crankshaft damper. Place
another mark on the vibration damper in alignment
with the mark you just made on the cover.(10) Divide the crankshaft damper into three
equally sized segments as follows:
(a) Using a tape measure, measure the circum-
ference of the crankshaft damper and divide the
measurement by three (3).
(b) Measure that distance in a counter-clockwise
direction from the first balancer mark and place
another mark on the balancer.
(c) From the second damper mark, again mea-
sure in a counter-clockwise direction and place a
mark on the damper at the same distance you
measured when placing the second damper mark.
The damper should now be marked in three
equally spaced locations and the damper TDC
mark should be in the 12 o'clock position.
(d) Remove injectors, fuel lines, and high pres-
sure connectors for every cylinder that requires
repair.
(11) Compress the valve springs at cyls. #1 and #6
as follows:
(a) Install the valve spring compressor mounting
base as shown in (Fig. 34).
(b) Install the top plate, washer, and nut. Using
a suitable wrench tighten the nut (clock-wise) (Fig.
35) to compress the valve springs and remove the
collets.
(c) Rotate the compressor nut counter-clockwise
to relieve tension on springs. Remove spring com-
pressor.
(d) Remove and replace retainers, springs, and
seals as necessary.
(e)Do not rotate the engine until the
springs and retainers are re-installed.
(f) Install seals, springs and retainers. Install
spring compressor, compress valve springs and
install the collets.
Fig. 32 Measuring Valve Lash - Typical
1 - INTAKE
2 - FEELER GAUGE
3 - EXHAUST
Fig. 33 Rotating Engine with Barring Tool - Typical
1 - REAR FLANGE
2 - BARRING TOOL
9 - 260 ENGINE 5.9L DIESELDR
INTAKE/EXHAUST VALVES & SEATS (Continued)

(g) Release the spring tension and remove the
compressor. Verify that the collets are seated by
tapping on the valve stem with a plastic hammer.
(12) Using the crankshaft barring tool, rotate the
engine until the next crankshaft damper paint mark
aligns with the mark you placed on the cover.In this
position, cylinders #2 and #5 can be serviced.
(13) Repeat the valve spring compressing proce-
dure previously performed and service the retainers,
springs, and seals as necessary.
(14) Using the crankshaft barring tool, rotate the
engine until the next crankshaft damper paint mark
aligns with the mark you placed on the cover.In this
position, cylinders #3 and #4 can be serviced.
(15) Repeat the spring compressing procedure pre-
viously performed and service the retainers, springs,
and seals as necessary.
INSTALLATION
(1) Install rocker housing.
(2) Install fuel injectors and high pressure fuel
lines.
(3) Lubricate the valve tips and install the cross-
heads in their original locations.
(4) Lubricate the crossheads and push rod sockets
and install the rocker arms and pedestals in their
original locations. Tighten bolts to 36 N´m (27 ft. lbs.)
torque.
(5)Verify valve lash adjustment (Refer to 9 -
ENGINE/CYLINDER HEAD/INTAKE/EXHAUST
VALVES & SEATS - STANDARD PROCEDURE).
(6) Install cylinder head cover and reusable gasket
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLIN-
DER HEAD COVER(S) - INSTALLATION).
(7) Connect battery negative cables.
ROCKER ARM / ADJUSTER
ASSY
DESCRIPTION
The unique intake and exhaust rocker arms have
their own rocker shafts and are lubricated by pas-
sages intersecting the cylinder block main oil rifle.
Crossheads are used, which allow each rocker arm to
operate two valves.
The solid push rods are hardened at the rocker
arm and tappet contact areas for superior strength
and durability.
REMOVAL
(1) Disconnect the battery negative cables.
(2) Remove cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(3) Remove the rocker arm/pedestal fasteners (Fig.
36) and remove rocker arm and pedestal from cylin-
der head. Mark the arms and pedestals so they can
be installed in their original position.
CAUTION: When removing the rocker arms, the
sockets (Fig. 37) may come loose and fall into the
engine. Make sure they stay with the arm upon
removal/installation.
(4) Lift the push rod(s) up and out of the engine
(Fig. 38). Mark them so they can be installed in their
original position.
Fig. 34 Spring Compressor Mounting BaseÐPart of
Tool 8319±A
1 - COMPRESSOR MOUNTING BASE
Fig. 35 Compressing Valve Springs with Tool
8319±A
1 - SPECIAL TOOL 8319
DRENGINE 5.9L DIESEL 9 - 261
INTAKE/EXHAUST VALVES & SEATS (Continued)