1998 DODGE RAM 1500 oil pressure

INSTALLATION
(1) Position the oil pump onto the crankshaft and
install one oil pump retaining bolts.
(2) Position the primary timing chain tensioner
and install three retaining bolts.
(3) Tighten the oil pump and primary timing chain
tensioner retaining bolts to 28 N´m (250 in. lbs.) in
the sequence shown (Fig. 107).
(4) Install the secondary timing chain tensioners
and timing chains (Refer to 9 - ENGINE/VALVE
TIMING/TIMING BELT/CHAIN AND SPROCKETS -
INSTALLATION).
(5) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(6) Install the pick-up tube and oil pan (Refer to 9
- ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
INTAKE MANIFOLD
DESCRIPTION
The intake manifold is made of a composite mate-
rial and features long runners which maximizes low
end torque. The intake manifold uses single plane
sealing which consist of eight individual press in
place port gaskets to prevent leaks. Eight studs and
two bolts are used to fasten the intake to the head.
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.
WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine.
(2) Spray a small stream of water at the suspected
leak area.
(3) If a change in RPM is observed the area of the
suspected leak has been found.
(4) Repair as required.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove resonator assembly and air inlet hose.
(3) Disconnect throttle and speed control cables.
(4) Disconnect electrical connectors for the follow-
ing components:
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
(5) Disconnect brake booster hose and positive
crankcase ventilation (PCV) hose.
(6) Disconnect generator electrical connections.
(7) Disconnect air conditioning compressor electri-
cal connections.
(8) Disconnect left and right radio suppressor
straps.
(9) Disconnect and remove ignition coil towers
(Refer to 8 - ELECTRICAL/IGNITION CONTROL/
IGNITION COIL - REMOVAL).
(10) Remove top oil dipstick tube retaining bolt
and ground strap.
(11) Bleed fuel system (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY - STANDARD PROCE-
DURE).
(12) Remove fuel rail (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/FUEL RAIL - REMOVAL).
(13) Remove throttle body assembly and mounting
bracket.
(14) Drain cooling system below coolant tempera-
ture level (Refer to 7 - COOLING - STANDARD
PROCEDURE).
(15) Remove the heater hoses from the engine
front cover and the heater core.
Fig. 107 Oil Pump And Primary Timing Chain
Tensioner Tightening Sequence
DRENGINE - 4.7L 9 - 159
OIL PUMP (Continued)

(16) Unclip and remove heater hoses and tubes
from intake manifold (Fig. 108).
(17) Remove coolant temperature sensor (Refer to
7 - COOLING/ENGINE/ENGINE COOLANT TEM-
PERATURE SENSO - REMOVAL).
(18) Remove intake manifold retaining fasteners in
reverse order of tightening sequence (Fig. 109).
(19) Remove intake manifold.CLEANING
NOTE: There is NO approved repair procedure for the
intake manifold. If severe damage is found during
inspection, the intake manifold must be replaced.
Before installing the intake manifold thoroughly
clean the mating surfaces. Use a suitable cleaning
solvent, then air dry.
INSPECTION
(1) Inspect the intake sealing surface for cracks,
nicks and distortion.
(2) Inspect the intake manifold vacuum hose fit-
tings for looseness or blockage.
(3) Inspect the manifold to throttle body mating
surface for cracks, nicks and distortion.
INSTALLATION
(1) Install intake manifold gaskets.
(2) Position intake manifold.
(3) Install intake manifold retaining bolts and
tighten in sequence shown in (Fig. 109) to 12 N´m
(105 in. lbs.).
(4) Install left and right radio suppressor straps.
(5) Install throttle body assembly.
(6) Install throttle cable bracket.
(7) Connect throttle cable and speed control cable
to throttle body.
(8) Install fuel rail (Refer to 14 - FUEL SYSTEM/
FUEL DELIVERY/FUEL RAIL - INSTALLATION).
(9) Install ignition coil towers (Refer to 8 - ELEC-
TRICAL/IGNITION CONTROL/IGNITION COIL -
INSTALLATION).
(10) Position and install heater hoses and tubes
onto intake manifold.
(11) Install the heater hoses to the heater core and
engine front cover.
(12) Connect electrical connectors for the following
components:
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
²Ignition coil towers
²Fuel injectors
(13) Install top oil dipstick tube retaining bolt and
ground strap.
(14) Connect generator electrical connections.
(15) Connect Brake booster hose and Positive
crankcase ventilation (PCV) hose.
(16) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(17) Install resonator assembly and air inlet hose.
(18) Connect negative cable to battery.
Fig. 108 Heater Hoses and Tubes Removal /
Installation
1 - HEATER HOSES AND TUBES
2 - ROUTING/RETAINING CLIPS
Fig. 109 Intake Manifold Tightening Sequence
9 - 160 ENGINE - 4.7LDR
INTAKE MANIFOLD (Continued)

ENGINE - 5.7L
TABLE OF CONTENTS
page page
ENGINE - 5.7L
DESCRIPTION........................182
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION..........183
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - PERFORMANCE..........183
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL............185
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE............186
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE.....186
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - LUBRICATION............187
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL............188
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR
DAMAGED OR WORN THREADS........190
STANDARD PROCEDUREÐHYDROSTATIC
LOCK..............................190
REMOVAL............................190
INSTALLATION........................191
SPECIFICATIONS
5.7L ENGINE........................192
TORQUE...........................195
SPECIAL TOOLS
5.7L ENGINE........................196
AIR INTAKE SYSTEM
REMOVAL............................199
INSTALLATION........................199
CYLINDER HEAD
OPERATIONÐCYLINDER HEAD...........199
DIAGNOSIS AND TESTINGÐCYLINDER HEAD
GASKET FAILURE....................199
REMOVAL............................200
CLEANING...........................200
INSPECTION.........................200
INSTALLATION........................200
CYLINDER HEAD COVER(S)
REMOVAL............................201
INSTALLATION........................201
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION
DESCRIPTION - VALVE GUIDES.........202
DESCRIPTION.......................202
STANDARD PROCEDURE - REFACING.....202
REMOVAL............................203INSTALLATION........................203
ROCKER ARM / ADJUSTER ASSY
REMOVAL............................203
INSTALLATION........................203
VALVE STEM SEALS
DESCRIPTION........................203
VALVE SPRINGS
REMOVAL............................204
INSTALLATION........................204
ENGINE BLOCK
CLEANING...........................205
INSPECTION.........................205
CAMSHAFT & BEARINGS (IN BLOCK)
REMOVAL
REMOVAL - CAMSHAFT CORE HOLE PLUG. 205
REMOVAL - CAMSHAFT...............205
INSPECTION.........................206
INSTALLATION
INSTALLATION - CAMSHAFT CORE HOLE
PLUG..............................206
INSTALLATION - CAMSHAFT............206
CRANKSHAFT
REMOVAL............................206
INSTALLATION........................207
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDURE - CRANKSHAFT
MAIN BEARING - FITTING..............207
INSPECTION.........................208
CRANKSHAFT OIL SEAL - FRONT
REMOVAL............................208
INSTALLATION........................208
CRANKSHAFT OIL SEAL - REAR
DIAGNOSIS AND TESTING - REAR SEAL
AREA LEAKS........................209
REMOVAL............................209
INSTALLATION........................209
CRANKSHAFT REAR OIL SEAL RETAINER
REMOVAL............................209
INSTALLATION........................210
FLEX PLATE
REMOVAL............................210
INSTALLATION........................210
HYDRAULIC TAPPETS
DIAGNOSIS AND TESTING - HYDRAULIC
TAPPETS...........................210
REMOVAL............................211
INSTALLATION........................211
PISTON & CONNECTING ROD
DESCRIPTION........................211
9 - 180 ENGINE - 5.7LDR

STANDARD PROCEDUREÐPISTON FITTING . 211
REMOVAL............................212
CLEANING...........................212
INSPECTION.........................213
INSTALLATION........................213
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING............................213
VIBRATION DAMPER
REMOVAL............................215
INSTALLATION........................215
STRUCTURAL COVER
DESCRIPTION........................216
OPERATION..........................216
REMOVAL............................216
INSTALLATION........................216
FRONT MOUNT
REMOVAL............................217
INSTALLATION........................218
REAR MOUNT
REMOVAL............................220
INSTALLATION........................220
LUBRICATION
DESCRIPTION........................220
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CHECKING
ENGINE OIL PRESSURE...............220
DIAGNOSIS AND TESTING - ENGINE OIL
LEAK..............................220
OIL
STANDARD PROCEDURE - ENGINE OIL
SERVICE...........................222
OIL FILTER
REMOVAL............................223INSTALLATION........................223
OIL PAN
REMOVAL............................224
INSTALLATION........................224
OIL PUMP
REMOVAL............................224
CLEANING...........................224
INSPECTION.........................224
INSTALLATION........................225
INTAKE MANIFOLD
DESCRIPTION........................225
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKAGE.................225
REMOVAL............................226
CLEANING...........................226
INSPECTION.........................226
INSTALLATION........................226
EXHAUST MANIFOLD
DESCRIPTION........................226
OPERATION..........................226
REMOVAL............................226
CLEANING...........................226
INSPECTION.........................227
INSTALLATION........................227
TIMING/CHAIN COVER
REMOVAL............................227
INSTALLATION........................227
TIMING/CHAIN AND SPROCKETS
REMOVAL............................228
INSTALLATION........................228
TIMING CHAIN/TENSIONER
DESCRIPTION........................229
OPERATION..........................229
DRENGINE - 5.7L 9 - 181

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION
Engine diagnosis is helpful in determining the
causes of malfunctions not detected and remedied by
routine maintenance.
These malfunctions may be classified as either per-
formance (e.g., engine idles rough and stalls) or
mechanical (e.g., a strange noise).
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING) - PERFORMANCE and (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)ÐMECHANICAL for
possible causes and corrections of malfunctions.
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
DIAGNOSIS AND TESTING) and (Refer to 14 -
FUEL SYSTEM/FUEL INJECTION - DIAGNOSIS
AND TESTING) for the fuel system diagnosis.Additional tests and diagnostic procedures may be
necessary for specific engine malfunctions that can
not be isolated with the Service Diagnosis charts.
Information concerning additional tests and diagno-
sis is provided within the following diagnosis:
²Cylinder Compression Pressure Test (Refer to 9 -
ENGINE - DIAGNOSIS AND TESTING).
²Cylinder Combustion Pressure Leakage Test
(Refer to 9 - ENGINE - DIAGNOSIS AND TEST-
ING).
²Engine Cylinder Head Gasket Failure Diagnosis
(Refer to 9 - ENGINE/CYLINDER HEAD - DIAGNO-
SIS AND TESTING).
²Intake Manifold Leakage Diagnosis (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
DIAGNOSIS AND TESTING).
DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - PERFORMANCE
CONDITION POSSIBLE CAUSE CORRECTION
ENGINE WILL NOT START 1. Weak battery 1. Charge or replace as necessary.
2. Corroded or loose battery
connections.2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to the terminals.
3. Faulty starter. 3. (Refer to 8 - ELECTRICAL/
STARTING - DIAGNOSIS AND
TESTING).
4. Faulty coil or control unit. 4. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION COIL
- REMOVAL).
5. Incorrect spark plug gap. 5. (Refer to 8 - ELECTRICAL/
IGNITION CONTROL/SPARK PLUG -
CLEANING).
6. Dirt or water in fuel system. 6. Clean system and replace fuel
filter.
7. Faulty fuel pump, relay or wiring. 7. Repair or replace as necessary.
DRENGINE - 5.7L 9 - 183
ENGINE - 5.7L (Continued)

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
6. Worn lash adjusters 6. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
8. Excessive runout of valve seats
on valve faces.8. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
DRENGINE - 5.7L 9 - 185
ENGINE - 5.7L (Continued)

DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs.
(3) Disable the fuel system (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY - DESCRIPTION).
(4) Remove the ASD relay (Refer to 8 - ELECTRI-
CAL/IGNITION CONTROL/AUTO SHUT DOWN
RELAY - REMOVAL).
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the 3rd
revolution. Continue the test for the remaining cylin-
ders.
(7) (Refer to 9 - ENGINE - SPECIFICATIONS) for
the correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing).²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss.
(1) Check the coolant level and fill as required. DO
NOT install the radiator cap.
(2) Start and operate the engine until it attains
normal operating temperature, then turn the engine
OFF.
(3) Remove the spark plugs.
(4) Remove the oil filler cap.
(5) Remove the air cleaner hose.
(6) Calibrate the tester according to the manufac-
turer's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
(7) Perform the test procedures on each cylinder
according to the tester manufacturer's instructions.
Set piston of cylinder to be tested at TDC compres-
sion,While testing, listen for pressurized air escaping
through the throttle body, tailpipe and oil filler cap
opening. Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder.
Refer to CYLINDER COMBUSTION PRESSURE
LEAKAGE DIAGNOSIS CHART.
CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
AIR ESCAPES THROUGH
THROTTLE BODYIntake valve bent, burnt, or not
seated properlyInspect valve and valve seat. Reface
or replace, as necessary. Inspect
valve springs. Replace as necessary.
AIR ESCAPES THROUGH TAILPIPE Exhaust valve bent, burnt, or not
seated properlyInspect valve and valve seat. Reface
or replace, as necessary. Inspect
valve springs. Replace as necessary.
AIR ESCAPES THROUGH
RADIATORHead gasket leaking or cracked
cylinder head or blockRemove cylinder head and inspect.
Replace defective part
MORE THAN 50% LEAKAGE FROM
ADJACENT CYLINDERSHead gasket leaking or crack in
cylinder head or block between
adjacent cylindersRemove cylinder head and inspect.
Replace gasket, head, or block as
necessary
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLYStuck or broken piston rings; cracked
piston; worn rings and/or cylinder wallInspect for broken rings or piston.
Measure ring gap and cylinder
diameter, taper and out-of-round.
Replace defective part as necessary
9 - 186 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

DIAGNOSIS AND TESTINGÐENGINE DIAGNOSIS - LUBRICATION
CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS 1. Gaskets and O-Rings. 1.
(a) Misaligned or damaged. (a) Replace as necessary.
(b) Loose fasteners, broken or
porous metal parts.(b) Tighten fasteners, Repair or
replace metal parts.
2. Crankshaft rear seal 2. Replace as necessary.
3. Crankshaft seal flange.
Scratched, nicked or grooved.3. Polish or replace crankshaft.
4. Oil pan flange cracked. 4. Replace oil pan.
5.Front cover seal, damaged or
misaligned.5. Replace seal.
6. Scratched or damaged vibration
damper hub.6. Polish or replace damper.
7. Crankshaft Rear Flange
Microporosity7. Replace Crankshaft
OIL PRESSURE DROP 1. Low oil level. 1. Check and correct oil level.
2. Faulty oil pressure sending unit. 2. Replace sending unit.
3. Low oil pressure. 3. Check pump and bearing
clearance.
4. Clogged oil filter. 4. Replace oil filter.
5. Worn oil pump. 5. Replace as necessary.
6. Thin or diluted oil. 6. Change oil and filter.
7. Excessive bearing clearance. 7. Replace as necessary.
8. Oil pump relief valve stuck. 8. Replace oil pump.
9. Oil pickup tube loose or
damaged.9. Replace as necessary.
OIL PUMPING AT RINGS; SPARK
PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings.
3. Incorrect ring size installed. 3. Replace rings.
4. Worn valve guides. 4. Ream guides and replace valves.
5. Leaking intake gasket. 5. Replace intake gaskets.
6. Leaking valve guide seals. 6. Replace valve guide seals.
DRENGINE - 5.7L 9 - 187
ENGINE - 5.7L (Continued)