1998 DODGE RAM 1500 air filter

(9) Install rocker housing and bolts. Tighten to 24
Nm (18 lb. ft.).
(10) Install fuel injector(Refer to 14 - FUEL SYS-
TEM/FUEL INJECTION/FUEL INJECTOR -
INSTALLATION).
(11) Install injector harness nuts. Tighten to 1.25
Nm (11 lb. in.).
(12) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(13) Install wire harness P-clip to cylinder head
behind filter housing 24 N´m (18 ft. lbs.).
(14) Connect the IAT/MAP sensor connector.
(15) Install the fuel filter canister assembly and
torque mounting bolts to 24 N´m (18 ft. lbs.).
(16) Connect fuel lift pump, WIF sensor, and fuel
heater.
(17) Remove the engine lift bracket at rear of cyl-
inder head.
CAUTION: Failure to follow procedure will result in
fuel leaks and/or fuel system failure.
(18)Install the fuel rail and high pressure
fuel lines as follows:
(a) Hand tighten fuel rail bolts.
(b) Hand tighten fuel drain line to pressure lim-
iting valve. Hand tighten banjo bolt at fuel filter
housing.
(c) Hand tighten fuel rail-to-cylinder head high
pressure fuel lines.(d) Install fuel line brace bolts-to-intake mani-
fold finger tight.
(e) Hand tighten fuel pump to fuel rail line.
(f) Torque fuel line nuts at cylinder head to 30
Nm ( 22 ft. lbs.).
(g) Torque fuel line nuts at fuel rail to 30 Nm
(22 ft. lbs.)
(h) Using a back up wrench, torque fuel pump to
fuel rail line to 37 Nm (27 ft. lbs.). At injection
pump.
(i) Torque fuel pump to fuel rail line to 37 Nm
(27 ft. lbs.) at fuel rail.
(j) Torque fuel drain banjo bolt at pressure lim-
iting valve and front of fuel filter housing to 24 Nm
(18 ft. lbs.).
(k) Torque fuel line brace bolts to 24 N´m (18 ft.
lbs.).
(l) Torque rail bolts to 24 Nm (18 ft. lbs.).
(m) Connect fuel pressure sensor.
(19) Install the engine lift bracket at the rear of
cylinder head. Torque to 77 N´m (57 ft. lbs.).
(20) Reposition number 6 fuel line shield and
torque to 43 N´m (32 ft. lbs.).
(21) Install the fuel filter to injection pump low
pressure line. Inspect and replace sealing washers if
necessary. Torque banjo bolts to 24 N´m (18 ft. lbs.).
(22) Connect fuel return line at back of cylinder
head hand tight.
(23) Connect fuel return line at filter housing hand
tight.
(24) Torque banjo connections at cylinder head and
fuel filter housing to 24 Nm (18 ft. lbs.)
(25) Install bracket to rear of filter housing.
Torque to 24 Nm (18 ft. lbs.).
(26) Using new gaskets, install the intake grid
heater and air inlet housing. Torque bolts to 24 N´m
(18 ft. lbs.).
(27) Install wire harness P-clip and push on clip to
air inlet housing.
(28) Connect engine oil level indicator tube at fuel
filter housing and at air inlet housing.
(29) Connect the APPS connector.
(30) Install the APPS assembly to the cylinder
head bracket and torque bolts to 24 N´m (18 ft. lbs.).
(31) Install the throttle linkage cover.
(32) Install the charge air cooler-to-air inlet hous-
ing duct assembly. Torque all clamps to 11 N´m (100
in. lbs.).
(33) Connect intake grid heater wires.
(34) Secure engine harness to front of cylinder
head with bolt at four locations.
(35) Connect engine coolant temperature sensor
connector.
(36) Connect radiator upper hose to thermostat
housing.
Fig. 20 Rocker Arm and Pedestal Removal
1 - ROCKER ARM
2 - PEDESTAL
9 - 254 ENGINE 5.9L DIESELDR
CYLINDER HEAD (Continued)

OIL COOLER & LINES
CLEANING
CLEANING AND INSPECTION
Clean the sealing surfaces.
Apply 483 kPa (70 psi) air pressure to the element
to check for leaks. If the element leaks, replace the
element.
OIL FILTER
REMOVAL
(1) Clean the area around the oil filter head.
Remove the filter from below using a cap-style filter
wrench.
(2) Clean the gasket surface of the filter head. The
filter canister O-Ring seal can stick on the filter
head. Make sure it is removed.
INSTALLATION
(1) Fill the oil filter element with clean oil before
installation. Use the same type oil that will be used
in the engine.
(2) Apply a light film of lubricating oil to the seal-
ing surface before installing the filter.
CAUTION: Mechanical over-tightening may distort
the threads or damage the filter element seal.
(3) Install the filter until it contacts the sealing
surface of the oil filter adapter. Tighten filter an
additional
1¤2turn.
OIL PAN
REMOVAL
(1) Disconnect the battery negative cables.
(2) Install engine support fixture # 8534.
(3) Raise vehicle on hoist.
(4) Disconnect starter cables from starter motor.
(5) Remove transmission and transfer case (if
equipped).
(6) Remove flywheel or flexplate.
(7) Remove starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL)
and transmission adapter plate assembly.
WARNING: HOT OIL CAN CAUSE PERSONAL
INJURY.
(8) Drain the engine oil (Refer to 9 - ENGINE/LU-
BRICATION/OIL - STANDARD PROCEDURE).(9) Install the oil pan drain plug if sealing surface
is not damaged and tighten to 50 N´m (37 ft. lbs.)
torque.
(10) Remove oil pan bolts, break the pan to block
seal, and lower pan slightly and remove oil suction
tube fasteners.
(11) Remove oil pan and suction tube.
CLEANING
Remove all gasket material from the oil pan and
cylinder block sealing surfaces. Extra effort may be
required around T-joint areas. Clean oil pan and
flush suction tube with a suitable solvent.
INSPECTION
Inspect the oil pan, suction tube, and tube braces
for cracks and damage. Replace any defective compo-
nent. Inspect the oil drain plug and drain hole
threads. Inspect the oil pan sealing surface for
straightness. Repair any minor imperfections with a
ball-peen hammer. Do not attempt to repair an oil
pan by welding.
INSTALLATION
(1) Fill the T-joint between the pan rail/gear hous-
ing and pan rail/rear seal retainer with sealant. Use
MopartSilicone Rubber Adhesive Sealant or equiva-
lent.
(2) Place suction tube in oil pan and guide them
into place. Using a new tube to block gasket, install
and tighten the suction tube bolts by hand. Starting
with the oil pump inlet bolts, tighten the bolts to 24
N´m (18 ft. lbs.) torque. Tighten the remaining tube
brace bolts to 43 N´m (32 ft. lbs.) torque.
(3) Starting in the center and working outward,
tighten the oil pan bolts to 28 N´m (21 ft. lbs.)
torque.
(4) Install the flywheel housing assembly with the
starter motor attached and tighten bolts to 77 N´m
(57 ft. lbs.) torque.
(5) Connect starter motor cables.
(6) Install the flywheel or flexplate. Torque to 137
N´m (101 ft. lbs.).
(7) Install transmission and transfer case (if
equipped).
(8) Lower vehicle.
(9) Remove the engine support fixture # 8534.
(10) Install battery negative cables.
(11) Fill the crankcase with new engine oil.
(12) Start engine and check for leaks. Stop engine,
check oil level, and adjust, if necessary.
DRENGINE 5.9L DIESEL 9 - 293

OIL PRESSURE RELIEF VALVE
REMOVAL
(1) Disconnect the battery negative cables.
(2) Remove the threaded plug, spring and plunger
(Fig. 108). 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. 109). Replace the spring if out of limits shown
in the figure.
INSTALLATION
(1) Install the plunger, spring, and plug as shown
in (Fig. 108). Tighten the plug to 80 N´m (59 ft. lbs.)
torque.
(2) Connect the battery negative cables.
(3) Start the engine and verify that it has oil pres-
sure.
OIL PRESSURE 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 power steering pump.
(7) Remove accessory drive belt tensioner.
(8) Remove the gear housing cover (Refer to 9 -
ENGINE/VALVE TIMING/GEAR HOUSING COVER
- REMOVAL).
Fig. 108 Oil Pressure Regulator
1 - OIL FILTER
2 - PLUG
3 - GASKET
4 - SPRING
5 - VALVE
Fig. 109 Oil Pressure Regulator Spring Check
9 - 294 ENGINE 5.9L DIESELDR

(13) Install the cooling fan (Refer to 7 - COOLING/
ENGINE/RADIATOR FAN - INSTALLATION).
(14) Connect battery negative cables.
(15) Start engine and check for oil leaks.
INTAKE MANIFOLD
REMOVAL
(1) Disconnect the battery negative cables.
(2) Remove the charge air cooler outlet tube from
the air inlet housing (Fig. 118).
(3) Remove the engine oil dipstick tube mounting
bolt (Fig. 118).
(4) Remove dipstick support at fuel filter housing.
Position dipstick tube to the side.
(5) Disconnect the air grid heater power cables at
the cable mounting studs.
(6) Disconnect the ground strap at the intake
cover.
(7) Remove the engine wiring harness connections
at the air inlet housing elbow.
(8) Remove the four (4) air inlet housing mounting
bolts and remove the housing from top of the heater
elements.
(9) Remove the intake air grid heater from the
manifold (Fig. 119).
(10) Remove the high pressure fuel lines and fuel
rail (Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/
FUEL LINES - REMOVAL).
(11) Remove APPS bracket from cylinder head to
gain access to front intake manifold cover bolts.
(12) Disconnect manifold air temperature/pressure
sensor connector.
(13) Remove the remaining intake manifold cover-
to-cylinder head bolts.
(14) Remove the intake manifold cover and gasket.
Keep the gasket material and any other material out
of the air intake.
(15) Clean the intake manifold cover and cylinder
head sealing surface.
CLEANING
Clean manifold in solvent and blow dry with com-
pressed air.
Clean cylinder block gasket surfaces using a suit-
able solvent.
The plenum pan rail must be clean and dry (free of
all foreign material).
INSPECTION
Inspect manifold for cracks.
Inspect mating surfaces of manifold for flatness
with a straightedge.
Fig. 118 Charge Air Cooler Air Tube
1 - FRONT WIRING CLIP
2 - GROUND CABLE
3 - TUBE BOLT
4 - ENGINE OIL DIPSTICK TUBE
5 - CLAMPS
6 - AIR TUBE (INT. MAN.-TO-INTERCOOLER)
7 - RUBBER HOSE
8 - AIR INTAKE HOUSING
9 - CABLE BRACKET HOUSING
Fig. 119 Intake Air Grid Heater
1 - INTAKE AIR GRID HEATER
2 - GASKET
DRENGINE 5.9L DIESEL 9 - 297
OIL PUMP (Continued)

INSTALLATION
(1) Using a new gasket, install the intake manifold
cover.
(2) Install the cover-to-cylinder head bolts that do
not hold down the fuel rail. Tighten the bolts to 24
N´m (18 ft. lbs.) torque.
(3) Install the high pressure rail and fuel lines
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/
FUEL LINES - INSTALLATION).
(4) Using two (2) new gaskets, install the intake
air grid heater and air inlet housing. Position the
ground cable and install and tighten the bolts to 24
N´m (18 ft. lbs.) torque.
(5) Connect the manifold air temperature/pressure
sensor connector.
(6) Install and tighten the air intake heater power
supply nuts to 14 N´m (120 in. lbs.) torque.
(7) Install the APPS bracket. Torque fasteners to
43 N´m (32ft lbs.) torque.
(8) Install oil dipstick tube support at fuel filter
housing.
(9) Install the engine oil dipstick tube and mount-
ing bolt.
(10) Position the charge air cooler outlet tube onto
the air inlet housing. Tighten the clamps to 11 N´m
(100 in. lbs.) torque.
(11) Attach the engine wire harness to the air inlet
housing at two locations.
(12) Prime the fuel system. Refer to the fuel prim-
ing procedure in Group 14, Fuel System.
(13) Connect the battery negative cables.
EXHAUST MANIFOLD
REMOVAL
(1) Disconnect the battery negative cables.
(2) Raise vehicle on hoist.
(3) Disconnect the exhaust pipe from the turbo-
charger elbow.
(4) Disconnect oil drain tube from turbocharger.
(5) Lower vehicle.
(6) Disconnect the turbocharger air inlet hose.
(7) Remove air cleaner assembly.
(8) Disconnect the turbocharger oil supply line.
(9) Disconnect the charge air cooler inlet pipe from
the turbocharger.
(10) Remove the turbocharger and gasket from the
exhaust manifold.
(11) Remove the cab heater return pipe nuts from
the exhaust manifold stud. Position the tube out of
the way.
(12) Remove heat shield.
(13) Remove exhaust manifold bolt lockplates.
(14) Remove the exhaust manifold-to-cylinder head
bolts and spacers (Fig. 120).(15) Remove the exhaust manifold and gaskets
(Fig. 120).
CLEANING
Clean the cylinder head and exhaust manifold seal-
ing surfaces with a suitable scraper. Use a Scotch-
BriteŸ pad or equivalent.
INSPECTION
Inspect the exhaust manifold for cracks. Measure
the exhaust manifold for flatness. Place a ruler over
all of the exhaust ports and insert a feeler gauge
between the port flange and the ruler. Maximum
deviation from flat is 0.20 mm (.008 inch).
INSTALLATION
(1) Using new gaskets, install the exhaust mani-
fold and gaskets. Install the bolts and spacers and
tighten the bolts in the sequence shown in to 43 N´m
(32 ft. lbs.) torque.
(2) Retorque the four center bolts.
Fig. 120 Exhaust Manifold and Gaskets
1 - RETAINING STRAP
2 - BOLT (7)
3 - SPACER
4 - MANIFOLD, EXHAUST
5 - GASKET
6 - BOLT (5)
9 - 298 ENGINE 5.9L DIESELDR
INTAKE MANIFOLD (Continued)

DIAGNOSIS AND TESTING - DIESEL ENGINE
EXHAUST SYSTEM DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
EXCESSIVE EXHAUST NOISE OR
LEAKING EXHAUST GASES1. Leaks at pipe joints. 1. Tighten clamps/bolts at leaking
joints.
2. Rusted or blown out muffler. 2. Replace muffler. Inspect exhaust
system.
3. Broken or rusted out exhaust
pipe.3. Replace exhaust pipe.
4. Exhaust pipe leaking at manifold
flange.4. Tighten/replace flange attaching
nuts/bolts.
5. Exhaust manifold cracked or
broken.5. Replace exhaust manifold.
6. Leak between exhaust manifold
and cylinder head.6. Tighten exhaust manifold to
cylinder head bolts. Replace gasket
if necessary.
7. Turbocharger mounting flange
cracked.7. Remove turbocharger and
inspect. (Refer to 11 - EXHAUST
SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER -
REMOVAL).
8. Restriction in exhaust system. 8. Remove restriction, if possible.
Replace restricted part if necessary.
SPECIFICATIONS - TORQUE
DESCRIPTION N´m Ft.
Lbs.In.
Lbs.
Bolt-Adjusting Strap 23 - 200
Nuts-Air Heater Power
Supply14 - 124
Bolts-Air Inlet Housing 24 18 -
Nuts-Cab Heater Supply/
Return Line24 18 -
Nuts-Exhaust Clamp 54.3 40 -
Bolts-Exhaust Manifold to
Cylinder Head-(Diesel
Engine)43 32 -
Bolts-Exhaust Manifold to
Cylinder Head-(5.9L)31 23 -
Bolts-Exhaust Manifold to
Cylinder Head-(8.0L)22 - 195
Bolts-Exhaust Pipe to
Manifold31 23 -
Bolts-Generator Mounting 41 30 -
DESCRIPTION N´m Ft.
Lbs.In.
Lbs.
Bolts-Charge Air Cooler
Mounting2-17
Nuts-Charge Air Cooler Duct 11 - 95
Bolt-Generator to Block-
Diesel24 18 -
Nuts and Bolts-Heat Shield 11 - 95
Turbocharger flange studs 24 18 -
Nuts-Turbocharger Mounting 43 32 -
Bolts-Turbocharger Oil Drain
Tube24 18 -
Fitting-Turbocharger Oil
Supply Line24 18 -
Nut-Turbocharger V-Band
Clamp5.6 - 70
Turbocharger Oil Supply
fitting (at Turbocharger)36 27 -
Turbocharger Oil Supply
fitting (at lube filter head)24 18 -
Turbocharger Drain Hose
Clamps8-71
DREXHAUST SYSTEM 11 - 5
EXHAUST SYSTEM (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)

TURBOCHARGER(COOL DOWN(CHART
Driving
ConditionLoad Turbo-
charger
Temper-
atureIdle Time (in
minutes)
Before Shut
Down
Stop & Go Empty Cool Less than 1
Stop & Go Medium Warm 1
Highway
SpeedsMedium Warm 2
City Traffic Max.
GCWRWarm 3
Highway
SpeedsMax.
GCWRWarm 4
Uphill Grade Max.
GCWRHot 5
REMOVAL
(1) Disconnect the battery negative cables.
(2) Raise vehicle on hoist.
(3) Disconnect the exhaust pipe from the turbo-
charger elbow(Refer to 11 - EXHAUST SYSTEM/EX-
HAUST PIPE - REMOVAL).
(4) Remove the bolts from the turbocharger oil
drain tube.
(5) Lower vehicle.
(6) Disconnect the turbocharger air inlet hose (Fig.
18).
(7) Disconnect the turbocharger oil supply line
from the turbocharger (Fig. 19).
(8) Disconnect the charge air cooler inlet pipe from
the turbocharger compressor outlet (Fig. 19).
Fig. 17 Turbocharger Oil Supply and Drain
1 - BEARINGS
2 - OIL SUPPLY (FROM FILTER HEAD)
3 - OIL RETURN (TO SUMP)
Fig. 18 Turbocharger Air Inlet Hose
1 - AIR INLET TUBE
2 - AIR FILTER HOUSING
3 - TURBOCHARGER
Fig. 19 Oil Supply Line and Charge Air Cooler Inlet
Duct
1 - TURBOCHARGERR EXHAUST ELBOW
2 - TURBOCHARGER
3 - OIL SUPPLY LINE
4 - AIR INLET TUBE
5 - TURBOCHARGER COMPRESSOR OUTLET
6 - OIL DRAIN LINE
11 - 14 EXHAUST SYSTEMDR
TURBOCHARGER (Continued)