1998 DODGE RAM 1500 engine

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
ENGINE MECHANICAL DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES/LIFTERS 1. High or low oil level in crankcase 1. Check for correct oil level. Adjust
oil level by draining or adding as
needed
2. Thin or diluted oil 2. Change oil. (Refer to 9 -
ENGINE/LUBRICATION/OIL -
STANDARD PROCEDURE)
3. Low oil pressure 3. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) for
engine oil pressure test/
specifications
4. Dirt in tappets/lash adjusters 4. Clean/replace hydraulic
tappets/lash adjusters
5. Bent push rod(s) 5. Install new push rods
6. Worn rocker arms 6. Inspect oil supply to rocker arms
and replace worn arms as needed
7. Worn tappets/lash adjusters 7. Install new hydraulic tappets/lash
adjusters
8. Worn valve guides 8. Inspect all valve guides and
replace as necessary
9. Excessive runout of valve seats
or valve faces9. Grind valves and seats
CONNECTING ROD NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) engine
oil pressure test/specifications
3. Thin or diluted oil 3. Change oil to correct viscosity.
(Refer to 9 - ENGINE/
LUBRICATION/OIL - STANDARD
PROCEDURE) for correct
procedure/engine oil specifications
4. Excessive connecting rod
bearing clearance4. Measure bearings for correct
clearance with plasti-gage. Repair
as necessary
5. Connecting rod journal out of
round5. Replace crankshaft or grind
journals
6. Misaligned connecting rods 6. Replace bent connecting rods
9 - 188 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
MAIN BEARING NOISE 1. Insufficient oil supply 1. Check engine oil level.
2. Low oil pressure 2. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING)
3. Thin or diluted oil 3. Change oil to correct viscosity.
4. Excessive main bearing
clearance4. Measure bearings for correct
clearance. Repair as necessary
5. Excessive end play 5. Check crankshaft thrust bearing
for excessive wear on flanges
6. Crankshaft main journal out of
round or worn6. Grind journals or replace
crankshaft
7. Loose flywheel or torque
converter7. Inspect crankshaft, flexplate/
flywheel and bolts for damage.
Tighten to correct torque
LOW OIL PRESSURE 1. Low oil level 1. Check oil level and fill if
necessary
2. Faulty oil pressure sending unit 2. Install new sending unit
3. Clogged oil filter 3. Install new oil filter
4. Worn oil pump 4. Replace oil pump assembly.
5. Thin or diluted oil 5. Change oil to correct viscosity.
6. Excessive bearing clearance 6. Measure bearings for correct
clearance
7. Oil pump relief valve stuck 7. Remove valve to inspect, clean
and reinstall
8. Oil pickup tube loose, broken,
bent or clogged8. Inspect oil pickup tube and pump,
and clean or replace if necessary
9. Oil pump cover warped or
cracked9. Install new oil pump
OIL LEAKS 1. Misaligned or deteriorated
gaskets1. Replace gasket
2. Loose fastener, broken or porous
metal part2. Tighten, repair or replace the part
3. Front or rear crankshaft oil seal
leaking3. Replace seal
4. Leaking oil gallery plug or cup
plug4. Remove and reseal threaded
plug. Replace cup style plug
DRENGINE - 5.7L 9 - 189
ENGINE - 5.7L (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
EXCESSIVE OIL CONSUMPTION OR
SPARK PLUGS OIL FOULED1. CCV System malfunction 1. (Refer to 25 - EMISSIONS
CONTROL/EVAPORATIVE
EMISSIONS - DESCRIPTION) for
correct operation
2. Defective valve stem seal(s) 2. Repair or replace seal(s)
3. Worn or broken piston rings 3. Hone cylinder bores. Install new
rings
4. Scuffed pistons/cylinder walls 4. Hone cylinder bores and replace
pistons as required
5. Carbon in oil control ring groove 5. Remove rings and de-carbon piston
6. Worn valve guides 6. Inspect/replace valve guides as
necessary
7. Piston rings fitted too tightly in
grooves7. Remove rings and check ring end
gap and side clearance. Replace if
necessary
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR DAMAGED
OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain
the original center line.
Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
STANDARD PROCEDUREÐHYDROSTATIC
LOCK
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Perform the Fuel Pressure Release Procedure
(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY -
STANDARD PROCEDURE).
(2) Disconnect the negative cable(s) from the bat-
tery.
(3) Inspect air cleaner, induction system, and
intake manifold to ensure system is dry and clear of
foreign material.
(4) Place a shop towel around the spark plugs to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the spark plugs.(5) With all spark plugs removed, rotate the crank-
shaft using a breaker bar and socket.
(6) Identify the fluid in the cylinders (coolant, fuel,
oil, etc.).
(7) Be sure all fluid has been removed from the
cylinders.
(8) Repair engine or components as necessary to
prevent this problem from occurring again.
(9) Squirt a small amount of engine oil into the
cylinders to lubricate the walls. This will prevent
damage on restart.
(10) Install new spark plugs. Tighten the spark
plugs to 41 N´m (30 ft. lbs.) torque.
(11) Drain engine oil. Remove and discard the oil
filter.
(12) Install the drain plug. Tighten the plug to 34
N´m (25 ft. lbs.) torque.
(13) Install a new oil filter.
(14) Fill engine crankcase with the specified
amount and grade of oil. (Refer to LUBRICATION &
MAINTENANCE - SPECIFICATIONS).
(15) Connect the negative cable(s) to the battery.
(16) Start the engine and check for any leaks.
REMOVAL
(1) Perform the Fuel System Pressure Release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE).
(2) Disconnect the battery negative cable.
(3) Remove the air cleaner resonator and duct
work as an assembly.
(4) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(5) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
9 - 190 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

(6) Remove the viscous fan/drive (Refer to 7 -
COOLING/ENGINE/RADIATOR FAN - REMOVAL).
(7) Remove radiator (Refer to 7 - COOLING/EN-
GINE/RADIATOR - REMOVAL).
(8) Remove the upper crossmember and top core
support.
NOTE: It is not necessary to drain A/C system for
engine removal.
(9) Remove the A/C compressor with the lines
attached. Secure compressor out of the way.
(10) Remove generator assembly (Refer to 8 -
ELECTRICAL/CHARGING/GENERATOR -
REMOVAL).
(11) Remove the intake manifold and IAFM as an
assembly(Refer to 9 - ENGINE/MANIFOLDS/IN-
TAKE MANIFOLD - REMOVAL).
(12) Disconnect the heater hoses.
NOTE: It is not necessary to disconnect P/S hoses
from pump, for P/S pump removal.
(13) Remove the power steering pump and set
aside.
(14) Disconnect the fuel supply line (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/QUICK CON-
NECT FITTING - STANDARD PROCEDURE).
(15) Raise and support the vehicle on a hoist and
drain the engine oil.
(16) Remove engine front mount thru-bolt nuts.
(17) Remove right side axle retaining bolts.
(18) Disconnect the transmission oil cooler lines
from their retainers at the oil pan bolts.
(19) Disconnect exhaust pipe at manifolds.
(20) Disconnect the starter wires. Remove starter
motor (Refer to 8 - ELECTRICAL/STARTING/
STARTER MOTOR - REMOVAL).
(21) Remove the structural dust cover and trans-
mission inspection cover,(Refer to 9 - ENGINE/EN-
GINE BLOCK/STRUCTURAL COVER - REMOVAL).
(22) Remove drive plate to converter bolts (Auto-
matic transmission equipped vehicles).
(23) Remove transmission bell housing to engine
block bolts.
(24) Lower the vehicle.
(25) Install engine lift fixture, special tool # 8984.
(26) Separate engine from transmission, remove
engine from vehicle, and install engine assembly on a
repair stand.
INSTALLATION
(1) Install engine lift fixture Special tool # 8984.
(2) Position the engine in the engine compartment.
(3) Lower engine into compartment and align
engine with transmission:²Manual Transmission: Align clutch disc assem-
bly (if disturbed). Install transmission input shaft
into clutch disc while mating engine and transmis-
sion surfaces. Install two transmission to engine
block mounting bolts finger tight.
²Automatic Transmission: Mate engine and trans-
mission and install two transmission to engine block
mounting bolts finger tight.
(4) Position the thru-bolt into the support cushion
brackets.
(5) Lower engine assembly until engine mount
through bolts rest in mount perches.
(6) Install remaining transmission to engine block
mounting bolts and tighten.
(7) Tighten engine mount through bolts.
(8) Install drive plate to torque converter bolts.
(Automatic transmission models)
(9) Install the structural dust cover and transmis-
sion dust cover,(Refer to 9 - ENGINE/ENGINE
BLOCK/STRUCTURAL COVER - INSTALLATION).
(10) Install the starter and connect the starter
wires (Refer to 8 - ELECTRICAL/STARTING/
STARTER MOTOR - INSTALLATION).
(11) Install exhaust pipe to manifold.
(12) Lower the vehicle.
(13) Remove engine lift fixture, special tool # 8984.
(14) Connect the fuel supply line (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/QUICK CON-
NECT FITTING - STANDARD PROCEDURE).
(15) Reinstall the power steering pump.
(16) Connect the heater hoses.
(17) Install the intake manifold.
(18) Using a new gasket, install throttle body
(Refer to 14 - FUEL SYSTEM/FUEL INJECTION/
THROTTLE BODY - INSTALLATION).
(19) Install the generator and wire connections
(Refer to 8 - ELECTRICAL/CHARGING/GENERA-
TOR - INSTALLATION).
(20) Install a/c compressor and lines (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/A/C
COMPRESSOR - INSTALLATION).
(21) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(22) Install upper radiator support crossmember.
(23) Install radiator (Refer to 7 - COOLING/EN-
GINE/RADIATOR - INSTALLATION).
(24) Connect the radiator lower hose.
(25) Connect the transmission oil cooler lines to
the radiator.
(26) Install the fan shroud.
(27) Install the fan (Refer to 7 - COOLING/EN-
GINE/RADIATOR FAN - INSTALLATION).
(28) Connect the radiator upper hose.
(29) Install the washer bottle.
(30) Connect the transmission cooler lines.
DRENGINE - 5.7L 9 - 191
ENGINE - 5.7L (Continued)

(31)Install the air cleaner resonator and duct work..
(32) Add engine oil to crankcase (Refer to LUBRI-
CATION & MAINTENANCE/FLUID TYPES - SPEC-
IFICATIONS).
(33) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(34) Connect battery negative cable.
(35) Start engine and inspect for leaks.
(36) Road test vehicle.
SPECIFICATIONS
5.7L ENGINE
GENERAL DESCRIPTION
DESCRIPTION SPECIFICATION
Engine Type 90É V-8 OHV
Displacement 5.7 Liters
345 ( Cubic Inches)
Bore 99.5 mm (3.91 in.)
Stroke 90.9 mm (3.58 in.)
Compression Ratio 9.6:1
Firing Order 1-8-4-3-6-5-7-2
Lubrication Pressure Feed - Full
Flow
Filtration
Cooling System Liquid Cooled - Forced
Circulation
Cylinder Block Cast Iron
Cylinder Head Aluminum
Crankshaft Nodular Iron
Camshaft Hollow Assembled
Camshaft
Pistons Aluminum Alloy
Connecting Rods Powdered Metal
CYLINDER BLOCK
DESCRIPTION SPECIFICATION
Metric Standard
Cylinder Bore
Diameter99.50 mm 3.917 in.
Out of Round
(MAX)0.0076 mm 0003 in.
Taper (MAX) 0.0127 mm 0.0005 in.
Lifter Bore
Diameter21.45 - 21.425
mm0.8444 - 0.8435
in.
PISTONS
DESCRIPTION SPECIFICATION
Metric Standard
Clearance at
Top of Skirt0.0215 - 0.0485
mm0.0008 - 0.0019
in.
Measured at
45.0 mm ( 1.77
in.) Below Deck
Land Clearance
Diameter
Groove #1 0.6715 - 0.7105
mm0.0264 - 0.0279
in.
Groove #2 0.5455 - 0.6245
mm0.0214 - 0.0245
in.
Weight 413 grams 14.56 oz
Piston Length 54.70 - 55.30 2.153 - 2.177 in.
Ring Groove
Width
No. 1 1.51 - 1.54 mm 0.0594 - 0.0606
in
No. 2 1.51 - 1.53 mm 0.0594 - 0.0602
in.
No. 3 3.030 - 3.055
mm0.1192 - 0.1202
in.
PISTON PINS
DESCRIPTION SPECIFICATION
Metric Standard
Clearance In
Piston0.009 - 0.018
mm0.00035 -
0.0007 in.
Diameter 24.0 - 24.003
mm0.9448 - 0.9449
in.
Length 70.53 - 71.03
mm2.78 - 2.80 in.
9 - 192 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

PISTON RINGS
DESCRIPTION SPECIFICATION
Metric Standard
Ring Gap
To p
Compression
Ring0.23 - 0.38 mm 0.0090 - 0.0149
in.
Second
Compression
Ring0.35 - 0.60 mm 0.0137 - 0.0236
in.
Oil Control
(Steel Rails)0.15 - 0.66 mm 0.0059 - 0.0259
in.
Side Clearance
To p
Compression
Ring.02 - .068 mm 0.0007 - 0.0026
in.
Second
Compression
Ring0.02 - 0.058
mm0.0007 - 0.0022
in.
Oil Ring (Steel
Ring).019 - .229 mm .0007 - .0091 in.
Ring Width
To p
Compression
Ring1.472 - 1.490
mm0.0579 - 0.0586
in.
Second
Compression
Ring1.472 - 1.490
mm0.0579 - 0.0586
in.
Oil Ring (Steel
Rails)0.447 - 0.473
mm0.0175 - 0.0186
in.
CONNECTING RODS
DESCRIPTION SPECIFICATION
Metric Standard
Piston Pin Bore
Diameter23.955 - 23.975
mm0.9431 - 0.9438
in.
Side Clearance 0.10 - 0.35 mm 0.003 - 0.0137
in.
CRANKSHAFT
DESCRIPTION SPECIFICATION
Metric Standard
Main Bearing
Journal Diameter64.988 -
65.012 mm2.5585 -
2.5595 in.
Bearing Clearance 0.023 - 0.051
mm0.0009 - 0.002
in.
Out of Round
(MAX)0.005 mm 0.0002 in.
Taper (MAX) 0.003 mm 0.0001 in.
End Play 0.052 - 0.282
mm0.002 - 0.011
in.
End Play (MAX) 0.282 mm 0.011 in.
Connecting Rod
Journal Diameter53.992 -
54.008 mm2.125 - 2.126
in.
Bearing Clearance 0.020 - 0.060
mm0.0007 -
0.0023 in.
Out of Round
(MAX)0.005 mm 0.0002 in.
Taper (MAX) 0.003 mm 0.0001 in.
CAMSHAFT
DESCRIPTION SPECIFICATION
Metric Standard
Bearing Journal
Diameter
No. 1 58.2 mm 2.29 in.
No. 2 57.8 mm 2.27 in.
No. 3 57.4 mm 2.26 in.
No. 4 57.0 mm 2.24 in.
No. 5 43.633 mm 1.72 in.
Bearing To Journal
Clearance
Standard
No. 1 0.040 - 0.080
mm.0015 - .003
in.
No. 2 0.050 -0.090
mm0.0019 - .0035
in.
No. 3 0.040 - 0.080
mm.0015 - .003
in.
No. 4 0.050 - 0.090
mm0.0019 - .0035
in.
No. 5 0.040 - 0.080
mm.0015 - .003
in.
Camshaft End Play .080 -
0.290mm0.0031 -
0.0114 in.
DRENGINE - 5.7L 9 - 193
ENGINE - 5.7L (Continued)

VALVE TIMING
DESCRIPTION SPECIFICATION
Intake
Opens (BTDC) 7.0É
Closes (ATDC) 253.0É
Exhaust
Opens (BTDC) 233É
Closes (ATDC) 27É
Duration 253.70É
Valve Overlap 34É
CYLINDER HEAD
DESCRIPTION SPECIFICATION
Valve Seat Angle 44.5É - 45.0É
Valve Seat Runout (MAX) 0.05 mm (0.0019 in.)
Valve Seat Width (Finish)
Intake 1.018 - 1.62 mm
(0.0464 - 0.0637 in.)
Exhaust 1.48 - 1.92 mm
(0.0582 - 0.0755 in.)
Guide Bore Diameter
(Std.)7.975 - 8.00 mm
(0.313 - 0.314 in.)
HYDRAULIC TAPPETS
DESCRIPTION SPECIFICATION
Metric Standard
Body Diameter 21.387 - 21.405
mm0.8420 - 0.8427
in.
Clearance (To
Bore)0.020 - 0.063
mm0.0007 - 0.0024
in.
Dry Lash 3.0 mm (at the
valve)0.1181 in.
VALVES
DESCRIPTION SPECIFICATION
Face Angle 45.0É - 45.5É
Head Diameter
Intake 50.67 - 50.93 mm
(1.99 - 2.00 in.)
Exhaust 39.27 - 39.53 mm
(1.54 - 1.55 in.)
Length (Overall)
Intake 123.38 - 123.76 mm
(4.857 - 4.872 in.)
Exhaust 120.475 - 120.855 mm
(4.743 - 4.758 in.)
Stem Diameter
Intake 7.935 - 7.953 mm
(0.312 - 0.313 in.)
Exhaust 7.905 - 7.925 mm
(0.311 - 0.312 in.)
Stem - to - Guide
Clearance
Intake 0.022 - 0.065 mm
(0.0008 - 0.0025 in.)
Exhaust 0.050 - 0.095 mm
(0.0019 - 0.0037 in.)
Valve Lift ( @ Zero Lash)
Intake 12.0 mm (0.472 in.)
Exhaust 11.70 mm (0.460 in.)
9 - 194 ENGINE - 5.7LDR
ENGINE - 5.7L (Continued)

VALVE SPRING
DESCRIPTION SPECIFICATION
Spring Force (Valve
Closed)
Intake and Exhaust 422.0 N @ 46.0 mm
(95lbs. @ 1.81 in.)
Spring Force (Valve
Open)
Intake and Exhaust @ 33.5 mm
Number of Coils
Intake and Exhaust 7.4
Wire Diameter
Intake and Exhaust 5.39 ý 4.52 mm
(0.212 - 0.177 in.)
Installed Height (Spring
Seat to Bottom of
Retainer)
Intake and Exhaust 46.0 mm (1.81 in.)
OIL PUMP
DESCRIPTION SPECIFICATION
Clearance Over Rotors
(MAX)0.095 mm (0.0038 in.)
Outer Rotor to Pump
Body Clearance (MAX).235 mm (.009 in.)
Tip Clearance Between
Rotors (MAX)0.150 mm (0.006 in.)
OIL PRESSURE
SPECIFICATION SPECIFICATION
At Curb Idle Speed
(MIN)*25 kPa (4 psi)
@ 3000 rpm 170 - 758 kPa (25 - 110
psi)
* CAUTION: If pressure is zero at curb idle, DO
NOT run engine
TORQUE
TORQUE CHART 5.7L ENGINE
DESCRIPTION N´m Ft. In.
Lbs. Lbs.
Block Pipe Plugs
(1/4 NPT)20 Ð 177
(3/8 NPT) 27 Ð 240
Camshaft SprocketÐBolt 122 90 Ð
Camshaft Tensioner
PlateÐBolts28 Ð 250
Timing Chain Case CoverÐ
Bolts28 Ð 250
Lifting Stud 55 40 Ð
Connecting Rod CapÐBolts 21
plus
90É
Turn15
plus
90É
TurnÐ
Main Bearing CapÐBolts
M-1227
plus
90É
TurnÐÐ
Crossbolts
M-828 Ð Ð
Cylinder HeadÐBolts
M-12 Bolts
Step 1 34 25 Ð
Step 2 54 40 Ð
Step 3 Turn
90ÉTurn
90ÉÐ
M-8 Bolts Ð
Step 1 20 15 Ð
Step 2 34 25 Ð
Cylinder Head CoverÐBolts 8 Ð 70
Exhaust Manifold to Cylinder
Head25 Ð 220
Flexplate to crankshaftÐBolts 95 70 Ð
Flywheel to crankshaftÐBolts 75 55 Ð
Front InsulatorÐThrough
bolt/nut95 70 Ð
Front Insulator to Support
Bracket
ÐStud Nut (4WD) 41 30 Ð
ÐThrough Bolt/Nut (4WD) 102 75 Ð
Front Insulator to BlockÐ
Bolts (2WD)95 70 Ð
DRENGINE - 5.7L 9 - 195
ENGINE - 5.7L (Continued)