vin DODGE RAM 1500 1998 2.G Workshop Manual

(10) Drain engine oil. Remove and discard the oil
filter (Refer to 9 - ENGINE/LUBRICATION/OIL FIL-
TER - REMOVAL).
(11) Install the drain plug. Tighten the plug to 50
N´m (37 ft. lbs.) torque.
(12) Install a new oil filter (Refer to 9 - ENGINE/
LUBRICATION/OIL FILTER - INSTALLATION).
(13) Fill engine crankcase with the specified
amount and grade of oil (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES - SPECIFICA-
TIONS).
(14) Connect the negative cable(s) to the battery.
(15) Start the engine and check for any leaks.
REMOVAL
REMOVAL - ENGINE
(1) Disconnect both battery negative cables.
(2) Disconnect engine grid heater harness at grid
heater relays.
(3) Disconnect electrical connections from rear of
alternator.
(4) Recover A/C refrigerant. (Refer to 24 - HEAT-
ING & AIR CONDITIONING/PLUMBING - STAN-
DARD PROCEDURE).
(5) Raise vehicle on a hoist.
(6) Drain engine coolant (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(7) Remove engine oil drain plug and drain engine
oil.
(8) Reinstall drain plug. Tighten to 50N´m (37 ft.
lbs.) torque.
(9) Lower the vehicle.
(10) Remove fan/drive assembly. Refer to Section 7
± Fan/Drive Removal
(11) Remove radiator upper hose.
(12) Remove upper fan shroud mounting bolts.
(13) Disconnect the coolant recovery bottle hose
from the radiator fill neck and remove bottle.
(14) Using a 36mm wrench, remove viscous fan/
drive assembly. (Refer to 7 - COOLING/ENGINE/RA-
DIATOR FAN - REMOVAL).
(15) Remove cooling fan and shroud together.
(16) Disconnect heater core supply and return
hoses from the cylinder head fitting and coolant pipe.
(17) Raise vehicle on a hoist.
(18) Remove transmission and transfer case (if
equipped).
(19) Disconnect exhaust pipe from turbocharger
extension pipe.
(20) Disconnect engine harness to vehicle harness
connectors.
(21) Remove starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL).(22) Remove flywheel/flexplate.
(23) Remove transmission adapter
(24) Disconnect A/C suction/discharge hose from
the rear of the A/C compressor.
(25) Lower vehicle.
(26) Disconnect lower radiator hose from radiator
outlet.
(27) Automatic transmission models:
(28) Disconnect transmission oil cooler lines from
in front of radiator using special tool #6931
(29) Remove radiator. (Refer to 7 - COOLING/EN-
GINE/RADIATOR - REMOVAL).
(30) If A/C equipped, disconnect A/C condenser
refrigerant lines.
(31) Disconnect charge air cooler piping.
(32) Remove charge air cooler mounting bolts.
(33) Remove charge air cooler (and A/C condenser
if equipped) from vehicle.
(34) Remove damper and speed indicator ring from
front of engine.
(35) Disconnect engine block heater connector.
(36) Disconnect A/C compressor and pressure sen-
sor electrical connectors.
(37) Remove the passenger battery ground cable
from the engine block. Remove the driver side bat-
tery ground cable from the engine block.
(38) Remove power steering pump from engine by
removing 3 bolts.
(39) Remove accelerator linkage cover.
(40) Disconnect cables from on-engine APPS.
(41) Disconnect the ECM power connector.
(42) Disconnect the ECM ground wire from the
hydroform screw.
(43) Disconnect the fuel supply and return hoses.
(44) Remove the cylinder head cover. (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(45) Disconnect the 3 injector harness connectors
at the rocker housing. Disconnect the wire harnesses
from the injectors.
(46) Remove the rear engine lift bracket.
(47) Remove cylinder #4, #5, and #6 intake and
exhaust rocker arms, pedestals, and push tubes. Note
the original location for re-assembly.
(48) Loosen #6 fuel line shield bolts and rotate
shield out of the way.
(49) Remove cylinder #5 and #6 high pressure fuel
lines. Remove the fuel connector tube nut and fuel
connector tube. Remove cylinder #5 and #6 fuel injec-
tor.
(50) Remove rocker housing.
DRENGINE 5.9L DIESEL 9 - 241
ENGINE 5.9L DIESEL (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)

After finish honing is complete, immediately clean
the cylinder bores with a strong solution of laundry
detergent and hot water.
After rinsing, blow the block dry.
Check the bore cleanliness by wiping with a white,
lint-free, lightly- oiled cloth. There should be no grit
residue present.
If the block is not to be used right away, coat it
with a rust- preventing compound.
METHOD 2ÐREPAIR SLEEVE
If more than a 1.00 mm (0.03937 inch) diameter
oversize bore is required, the block must be bored
and a repair sleeve installed.
Bore the block cylinder bore to 104.500-104.515
mm (4.1142-4.1148 inch) - (Fig. 49).
Repair sleeves can be replaced by using a boring
bar to bore out the old sleeve. DO NOT cut the cyl-
inder bore beyond the oversize limit.
REPAIR SLEEVE BLOCK REBORE
DIMENSIONS CHART
BORE DIAMETER STEP DIMENSION
104.500 + 0.015 mm
(4.1142 + 0.0006 in.)6.35 mm (0.25 in.)
After machining the block for the new repair
sleeve, thoroughly clean the bore of all metal chips,
debris and oil residue before installing the sleeve.
Cool the repair sleeve(s) to a temperature of -12ÉC
(10ÉF) or below for a minimum of one hour. Be ready
to install the sleeve immediately after removing it
from the freezer.
Apply a coat of Loctite 620, or equivalent to the
bore that is to be sleeved.Wear protective gloves to push the cold sleeve into
the bore as far as possible.
Using a sleeve driver, drive the sleeve downward
until it contacts the step at the bottom of the bore
(Fig. 50).
A sleeve driver can be constructed as follows (Fig.
51).SLEEVE DRIVER CONSTRUCTION
SPECIFICATION CHART
ITEM MEASUREMENT
A 127 mm (5 in.)
B 38 mm (1.5 in.)
C 6.35 mm (0.25 in.)
D 25.4 mm (1 in.)
E 101 mm (3.976 in.)
F 107.343 mm (4.226 in.)
Set up a boring bar and machine the sleeve to
101.956 mm (4.014 inch).
Fig. 49 Block Bore for Repair Sleeve Dimensions
1 - BORE DIAMETER
2 - STEP DIMENSION
Fig. 50 Sleeve Installation
1 - SLEEVE DRIVER
2 - SLEEVE
3 - CONTACT
Fig. 51 Sleeve Driver Construction
1 - DRIVE
2 - HANDLE
9 - 266 ENGINE 5.9L DIESELDR
ENGINE BLOCK (Continued)

After removing the boring bar, use a honing stone
to chamfer the corner of the repair sleeve(s).
SLEEVE MACHINING DIMENSIONS CHART
ITEM MEASUREMENT
SLEEVE PROTRUSION MIN. - FLUSH WITH
BLOCK
MAX. - 0.050 mm
(0.0019 in.)
SLEEVE DIAMETER 101.956 mm (4.014 in.)
SLEEVE CHAMFER APPROX. 1.25 mm
(0.049 in.) by 15É
A correctly honed surface will have a crosshatch
appearance with the lines at 15É to 25É angles with
the top of the cylinder block. For the rough hone, use
80 grit honing stones. To finish hone, use 280 grit
honing stones.
Finished bore inside dimension is 102.020  0.020
mm (4.0165  0.0008 inch).
A maximum of 1.2 micrometer (48 microinch) sur-
face finish must be obtained.
After finish honing is complete, immediately clean
the cylinder bores with a strong solution of laundry
detergent and hot water.
After rinsing, blow the block dry with compressed
air.
Wipe the bore with a white, lint-free, lightly oiled
cloth. Make sure there is no grit residue present.
Apply a rust-preventing compound if the block will
not be used immediately.
A standard diameter piston and a piston ring set
must be used with a sleeved cylinder bore.
STANDARD PROCEDUREÐCAM BORE REPAIR
For standard bushings, not oversized, maximum
front and rear cam bushing bore diameter is 59.248
mm. (2.3326 in.). DO NOT bore the intermediate cam
bore to the front cam bore oversize dimensions. Max-
imum front and rear camshaft bushing installed
diameter is 54.147 mm. (2.1318 in.). Minimum
installed diameter is 54.083 mm. (2.1293 in.). Maxi-
mum intermediate camshaft bore diameter is 54.164
mm. (2.1324 in.).
A surface finish of 2.3 micrometers (92 microinch)
must be maintained. Not more than 20% of an area
of any one bore may be 3.2 micrometers (126 micro-
inch).
Camshaft bores can be repaired individually. It is
not necessary to repair undamaged cam bores in
order to repair individually damaged cam bores. The
standard front bushing cannot be used to repair
intermediate bores.Install all cam bushings flush or below the front
and rear cam bore surface. The front camshaft bush-
ing should be installed flush with front face of block.
The rear camshaft bushing should be installed flush
with rear face of block. The oil hole must align to
allow a 3.2 mm (0.125 inch) rod to pass through
freely (Fig. 52).
INSPECTION
Measure the combustion deck face using a straight
edge and a feeler gauge (Fig. 53). Cylinder block flat-
ness: End-to-end 0.076 mm ( .003 in.). Maximum
variation side-to-side 0.051 mm (.002 in.).
Inspect for any localized dips or imperfections.
If the surface exceeds the limit, (Refer to 9 -
ENGINE/ENGINE BLOCK - STANDARD PROCE-
DURE).
Fig. 52 Oil Hole Alignment
1 - CAMSHAFT BUSHING
Fig. 53 Combustion Deck Face Measurement
1 - STRAIGHT EDGE
2 - FEELER GAUGE
DRENGINE 5.9L DIESEL 9 - 267
ENGINE BLOCK (Continued)

If the crankshaft is within limits, replace the bear-
ing. If the crankshaft is out of limits, grind the
crankshaft to the next smaller size and use oversize
rod bearings.
CRANKSHAFT AND GEAR
DESCRIPTION
The crankshaft (Fig. 64) is a forged steel, integrally
balanced unit. It is supported by seven main bear-
ings, with position number six designated as the
thrust journal. The crankshaft is held in place by
main caps and 12 mm capscrews. The crankshaft
also has internal cross drillings to supply the con-
necting rods with engine oil.
REMOVAL - GEAR
(1) Remove the gear housing cover. (Refer to 9 -
ENGINE/VALVE TIMING/GEAR HOUSING COVER
- REMOVAL)
(2) Split the gear and remove it from the crank-
shaft.
INSTALLATION - GEAR
(1) Remove all burrs and make sure the gear sur-
face on the end of the crankshaft is smooth.
(2) If removed, install a new alignment pin. Drive
the pin in using a ball- peen hammer, leaving it pro-truding 1.0 mm (0.039 inch) to 1.5 mm (0.059 inch)
above the crankshaft (Fig. 65).
WARNING: WEAR PROTECTIVE GLOVES TO PRE-
VENT INJURY.
CAUTION: DO NOT heat the gear longer than 45
minutes.
(3) Heat the crankshaft gear for 45 minutes at a
temperature of 149ÉC (300ÉF).Do not use torch,
gear failure will occur.
(4) Apply a thin coat of lubricant to the nose of the
crankshaft.
(5) Position the gear with the timing mark out and
install it on the crankshaft using the alignment pin.
Make sure the gear contacts the shoulder.
Fig. 63 Connecting Rod Journal Diameter Limits
CONNECTING ROD JOURNAL DIAMETER
LIMITS CHART
DESCRIPTION MEASUREMENT
CRANKSHAFT ROD JOURNAL
DIAMETERMin. 68.96 mm (2.715 in.)
Max. 69.01 mm (2.717 in.)
BEARING CLEARANCE Min. 0.04 mm (.002 in.)
Max. 0.12 mm (0.005 in.)
Fig. 64 Crankshaft
Fig. 65 Installing Alignment Pin
1 - ALIGNMENT PIN
DRENGINE 5.9L DIESEL 9 - 273
CONNECTING ROD BEARINGS (Continued)

CRANKSHAFT OIL SEAL - FRONT
REMOVAL
(1) Disconnect both 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 from radia-
tor 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 the fan shroud-to-radiator mounting bolts.
(9)Remove viscous fan/drive assembly. (Refer to 7 -
COOLING/ENGINE/RADIATOR FAN - REMOVAL).
(10) Remove cooling fan shroud and fan assembly
from the vehicle.
(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 and speed
indicator ring.
(15) Remove power steering pump.
(16) Remove accessory drive belt tensioner.
(17) Remove the gear cover-to-housing bolts and
gently pry the cover away from the housing, taking
care not to mar the gasket surfaces. Remove crank
seal dust shield with cover.
(18) Support the cover on a flat work surface with
wooden blocks (Fig. 68), and using a suitable punch
and hammer, drive the old seal out of the cover from
the back side of the cover to the front side (Fig. 68).
INSTALLATION
(1) Clean cover and housing gasket mating sur-
faces. Use a suitable scraper and be careful not to
damage the gear housing surface. Remove any old
sealer from the oil seal bore. Thoroughly clean the
front seal area of the crankshaft. The seal lip and the
sealing surface on the crankshaft must be free from
all oil residue to prevent seal leaks.
(2) Inspect the gear housing and cover for cracks
and replace if necessary. Carefully straighten any
bends or imperfections in the gear cover with a ball-
peen hammer on a flat surface. Inspect the crank-
shaft front journal for any grooves or nicks that
would affect the integrity of the new seal.
(3) Apply a bead of MopartStud & Bearing Mount
to the outside diameter of the seal. Do not lubricate
the inside diameter of the new seal.(4)
With the cover supported by wood blocks, install
the seal into the rear of the cover using crankshaft seal
installer Special Tool 8281 and driver handle C-4171
(Fig. 69). Strike the driver handle until the installation
tool bottoms out on the inside of the cover.
CAUTION: Do not distort or damage seal.
(5) Install the plastic seal pilot (provided with seal
kit) into the crankshaft seal.
Fig. 68 Removing Seal from Cover
1 - PUNCH
Fig. 69 Installing Seal Into Cover With Tool 8281
1 - SEAL INSTALLER 8281
2 - DRIVER HANDLE C4171
3 - SEAL
DRENGINE 5.9L DIESEL 9 - 275

PISTON & CONNECTING ROD
DESCRIPTION
PISTONS
The piston (Fig. 85) is constructed of aluminum
and is gravity cast, free floating design. The piston
incorporates a centrally located high swirl combus-
tion bowl, and utilizes a ªkeystoneº style top com-
pression ring (Fig. 86), and a ªTapered Faceº
intermediate ring (Fig. 86), for superior cylinder wall
scraping. Piston cooling nozzles cool the piston and
pin with engine oil supplied by the crankshaft main
journals. High horsepower pistons are gallery cooled
and utilize J-jet piston cooling nozzles. Pistons are
directional in order to provide clearance to piston
cooling nozzles.
CONNECTING RODS
The connecting rods are a split angle design. They
have a pressed-in-place wrist pin bushing that is
lubricated by piston cooling nozzle oil spray.
Machined connecting rods are no longer used
in the diesel engine. Do not install machined
connecting rods into an engine that has frac-
tured split connecting rods.
Fractured split connecting rods are first manufac-
tured as a single piece and then fractured into two
pieces. Fractured split connecting rods can be identi-
fied by a rough and irregular surface at the connect-
ing rod split face. To properly assemble the rod cap to
the connecting rod, the bearing tangs on the connect-
ing rod and cap must be located on the same side of
the rod. The long end of the connecting rod must be
assembled on the intake or camshaft side of the
engine.
Each matched fractured split connecting rod and
cap is an assembly and are not interchangeable. If a
connecting rod or cap is damaged, the entire assem-
bly must be replaced.
STANDARD PROCEDURE - HEAD GASKET
SELECTION
(1) Measure piston protrusion for all six pistons.
(2) Calculate the average piston protrusion. Maxi-
mum allowable protrusion is 0.516 mm (0.020 inch).
NOTE: There are two different head gaskets avail-
able. One gasket is for Average piston protrusion
less than 0.30 mm (0.011 inch). The other gasket is
for Average piston protrusion greater than 0.30 mm
(0.011 inch)
REMOVAL
(1) Disconnect the battery cables.
(2) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(3) Remove the oil pan and suction tube (Refer to 9
- ENGINE/LUBRICATION/OIL PAN - REMOVAL).
(4) Remove bolts and the block stiffener.
(5) Using Miller Tool 7471-B crankshaft barring
tool, rotate the crankshaft so all of the pistons are
below TDC.
(6) Before removing the piston(s) from the bore(s):
(a) Remove any carbon ridge formations or
deposits at the top of the bore with a dull scraper
or soft wire brush.
(b) If cylinder bore wear ridges are found, use a
ridge reamer to cut the ridge from the bore. DO
NOT remove more metal than necessary to remove
the ridge.
(7) Remove the J-jet cooling nozzles, if equipped.
Fig. 85 Piston - Typical
Fig. 86 Piston Ring Identification
DRENGINE 5.9L DIESEL 9 - 281

(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.
(27) Clean the gasket material from the cylinder
block and gear housing.
INSTALLATION
(1) Inspect oil pan gasket. If torn, gasket must be
replaced.
(2) Install a new gear housing gasket onto cylinder
block and trim any excesss gasket material flush to
oil pan rail.
(3) Install the gear housing. Torque bolts to 24
N´m (18 ft. lbs.) (Fig. 121).
(4) If a new housing is installed, the camshaft
position sensor, and engine speed sensor must be
transferred to the new housing.
(5) Connect the camshaft position sensor connec-
tor.
(6) Install and connect engine speed sensor.
(7) Install the injection pump (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL INJECTION
PUMP - INSTALLATION).
(8) Install the camshaft (Refer to 9 - ENGINE/EN-
GINE BLOCK/CAMSHAFT & BEARINGS (INBLOCK) - INSTALLATION). Align the crankshaft
and camshaft gear marks as shown in (Fig. 122).
(9) Install a new front crankshaft seal into the
gear cover.
(10) Apply a bead of MopartSilicone Rubber
Adhesive Sealant or equivalent to the gear housing
cover. Be sure to surround all through holes.
(11) Using the seal pilot to align the cover, install
the cover to the housing and install the bolts.
Tighten the bolts to 24 N´m (18 ft. lbs.) torque.
(12) Remove the seal pilot. Install front seal dust
shield.
(13) Raise the vehicle.
(14) Trim any excess gear housing gasket to make
it flush with the oil pan rail.
(15) Install the crankshaft damper and speed indi-
cator ring (Refer to 9 - ENGINE/ENGINE BLOCK/
VIBRATION DAMPER - INSTALLATION). Torque
bolts to 40 Nm (30 ft. lbs.), plus an additional 60É.
(16) Lower vehicle.
(17) Install the fan support/hub assembly and
tighten bolts to 32 N´m (24 ft. lbs.) torque.
(18) Install the power steering pump.
(19) Install the accessory drive belt tensioner.
Torque bolt to 43 N´m (32 ft. lbs.) torque.
(20) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(21) Install the upper cooling fan and shroud
together (Refer to 7 - COOLING/ENGINE/RADIA-
TOR FAN - INSTALLATION).
(22) Install lower shroud and connect fan drive
harness connector.
Fig. 121 GEAR HOUSING CAPSCREW TORQUE
SEQUENCE
Fig. 122 Timing Mark Alignment
9 - 300 ENGINE 5.9L DIESELDR
GEAR HOUSING (Continued)

INSTALLATION
(1) Install the tailpipe into the muffler.
(2) Install the tailpipe hanger rods into the isola-
tors (Fig. 11)
(3) Install the exhaust clamp, align the exhaust
system, and tighten the clamp 48 N´m (35 ft. lbs.)
torque.
(4) Lower the vehicle.
(5) Connect the battery negative cables.
(6) Start the engine and inspect for exhaust leaks.
Reair exhaust leaks as necessary.
(7) Check the exhaust system for contact with the
body panels. A minimum of 25.4 mm (1.0 in.) is
required between the exhaust system components
and body/frame parts. Make the necessary adjust-
ments, if needed..
TAILPIPE
REMOVAL
(1) Raise and support the vehicle.
(2) Saturate the clamp nuts with heat valve lubri-
cant. Allow 5 minutes for penetration.
(3) Disconnect the exhaust tailpipe support hanger
(Fig. 12).(4) Remove clamps and nuts.
(5) Remove the exhaust tailpipe.
INSPECTION
Discard rusted clamps, broken or worn supports
and attaching parts. Replace a component with orig-
inal equipment parts, or equivalent. This will assure
proper alignment with other parts in the system and
provide acceptable exhaust noise levels.
INSTALLATION
(1) Loosely assemble exhaust tailpipe to permit
proper alignment of all parts.
(2) Connect the support hangers.
(3) Position the exhaust tailpipe for proper clear-
ance with the underbody parts.
(4) Tighten all clamp nuts to 54.2 N´m (40 ft. lbs.)
torque.
(5) Lower the vehicle.
(6) Start the engine and inspect for exhaust leaks.
Reair exhaust leaks as necessary.
(7) Check the exhaust system for contact with the
body panels. A minimum of 25.4 mm (1.0 in.) is
required between the exhaust system components
and body/frame parts. Make the necessary adjust-
ments, if needed..
TURBOCHARGER SYSTEM
DIAGNOSIS AND TESTING - TURBOCHARGER
BOOST PRESSURE
NOTE: This diagnostic procedure is to be used with
the DRB IIITwhile test driving the vehicle under
normal load and driving conditions.
Low turbocharger boost pressure can cause poor
engine performance and driveability concerns. The
following procedure will test the turbocharger boost
pressure.
(1) Loosen clamps holding air inlet duct rubber
sleeve to the intake manifold and air inlet duct.
Remove rubber sleeve (Fig. 13).
(2) Position Special Tool 8462 onto air inlet duct
and intake manifold. Using the existing clamps
tighten to 8 N´m (72 in. lbs.).
(3) Install the 3447.5 kPa 500 psi (gray) Pressure
Transducer (part of OT-CH8520 Transducer Kit) into
Special Tool 8462.
(4) Connect the DRB IIItto the pressure trans-
ducer following the instructions supplied with the
DRB IIIt.
(5) Enter DRB IIItinto pressure reading mode
and test drive vehicle.
Fig. 12 TAILPIPE
1 - INSULATOR
2 - TAILPIPE
3 - CLAMP
4 - MUFFLER
5 - CLAMP
6 - INSULATOR
7 - INSULATOR
8 - INSULATOR
DREXHAUST SYSTEM 11 - 11
TAILPIPE - 5.9L DIESEL (Continued)

OPERATION
Exhaust gas pressure and energy drive the tur-
bine, which in turn drives a centrifugal compressor
that compresses the inlet air, and forces the air into
the engine through the charge air cooler and plumb-
ing. Since heat is a by-product of this compression,
the air must pass through a charge air cooler to cool
the incoming air and maintain power and efficiency.
Increasing air flow to the engine provides:
²Improved engine performance
²Lower exhaust smoke density
²Improved operating economy
²Altitude compensation
²Noise reduction.
The turbocharger also uses a wastegate (Fig. 16),
which regulates intake manifold air pressure and
prevents over boosting at high engine speeds. When
the wastegate valve is closed, all of the exhaust gases
flow through the turbine wheel. As the intake mani-
fold pressure increases, the wastegate actuator opens
the valve, diverting some of the exhaust gases away
from the turbine wheel. This limits turbine shaft
speed and air output from the impeller.
The turbocharger is lubricated by engine oil that is
pressurized, cooled, and filtered. The oil is delivered
to the turbocharger by a supply line that is tapped
into the oil filter head. The oil travels into the bear-
ing housing, where it lubricates the shaft and bear-
ings (Fig. 17). A return pipe at the bottom of the
bearing housing, routes the engine oil back to the
crankcase.
The most common turbocharger failure is bearing
failure related to repeated hot shutdowns with inad-
equate ªcool-downº periods. A sudden engine shut
down after prolonged operation will result in the
transfer of heat from the turbine section of the tur-
bocharger to the bearing housing. This causes the oil
to overheat and break down, which causes bearing
and shaft damage the next time the vehicle is
started.
Letting the engine idle after extended operation
allows the turbine housing to cool to normal operat-
ing temperature. The following chart should be used
as a guide in determining the amount of engine idle
time required to sufficiently cool down the turbo-
charger before shut down, depending upon the type
of driving and the amount of cargo.
Fig. 16 Wastegate Operation
1 - SIGNAL LINE
2 - EXHAUST BYPASS VALVE
3 - WASTEGATE
4 - EXHAUST
5 - TURBINE
DREXHAUST SYSTEM 11 - 13
TURBOCHARGER (Continued)