1998 DODGE RAM 1500 check engine

REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Remove the air cleaner(Refer to 9 - ENGINE/
AIR INTAKE SYSTEM - REMOVAL).
(3) Remove intake manifold(Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - REMOVAL).
(4) Remove cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(5) Remove rocker arm assembly and push rod-
s(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - REMOVAL). Identify
push rods to ensure installation in original location.
(6) Remove the cylinder head(Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(7) Remove bolt from tappet guide holder.
(8) Remove tappet guide holder.
(9) Pull tappet out of bore with a twisting motion.
If all tappets are to be removed and reused, identify
tappets to ensure installation in original location.
(10) Check camshaft lobes for abnormal wear.
INSTALLATION
(1) Lubricate tappets.
(2) Install tappets in their original positions.
(3)
Install tappet guide holder. Install the tappet
guide holder bolt and tighten to 12 N´m (106 in. lbs.)
torque.
(4) Install cylinder head(Refer to 9 - ENGINE/
CYLINDER HEAD - INSTALLATION).
(5) Install pushrods and rocker arm assembly(Re-
fer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - INSTALLATION).
(6) Install cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(7)
Install intake manifold(Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - INSTALLATION).
(8) Install the air cleaner(Refer to 9 - ENGINE/
AIR INTAKE SYSTEM - INSTALLATION).
(9) Connect the negative cable to the battery.
CAUTION: To prevent damage to valve mechanism,
engine must not be run above fast idle until all
hydraulic tappets have filled with oil and have
become quiet.
(10) Road test vehicle and check for leaks.
PISTON & CONNECTING ROD
DESCRIPTION
CAUTION: Do not use a metal stamp to mark con-
necting rods as damage may result, instead use ink
or a scratch awl.The pistons are made of a high strength aluminum
alloy. Piston skirts are coated with a solid lubricant
(Molykote) to reduce friction and provide scuff resis-
tance. The piston top ring groove and land is anod-
ized. The connecting rods are made of forged
powdered metal, with a ªfractured capº design. A
pressed fit piston pin is used to attach the piston and
connecting rod.
STANDARD PROCEDUREÐPISTON FITTING
(1) To correctly select the proper size piston, a cyl-
inder bore gauge, capable of reading in 0.003 mm (
.0001 in.) INCREMENTS is required. If a bore gauge
is not available, do not use an inside micrometer.
(2) Measure the inside diameter of the cylinder
bore at a point 38.0 mm (1.5 inches) below top of
bore. Start perpendicular (across or at 90 degrees) to
the axis of the crankshaft at point A and then take
an additional bore reading 90 degrees to that at point
B (Fig. 11).
(3) The coated pistons will be serviced with the
piston pin and connecting rod pre-assembled. The
piston-rod assembly is specific for the left cylinder
bank ( odd numbered) and the right cylinder bank (
even numbered) and must not be interchanged.
(4) The coating material is applied to the piston
after the final piston machining process. Measuring
the outside diameter of a coated piston will not pro-
vide accurate results (Fig. 10). Therefore measuring
the inside diameter of the cylinder bore with a dial
Bore Gauge isMANDATORY. To correctly select the
proper size piston, a cylinder bore gauge capable of
reading in 0.003 mm (.0001 in.) increments is
required.
Fig. 10 MOLY COATED PISTON
1 - MOLY COATED
2 - MOLY COATED
DRENGINE - 5.7L 9 - 211
HYDRAULIC TAPPETS (Continued)

INSPECTION
Check the connecting rod journal for excessive
wear, taper and scoring (Refer to 9 - ENGINE/EN-
GINE BLOCK/CONNECTING ROD BEARINGS -
STANDARD PROCEDURE).
Check the connecting rod for signs of twist or bend-
ing.
Check the piston for taper and elliptical shape
before it is fitted into the cylinder bore (Refer to 9 -
ENGINE/ENGINE BLOCK/PISTON & CONNECT-
ING ROD - STANDARD PROCEDURE).
Check the piston for scoring, or scraping marks in
the piston skirts. Check the ring lands for cracks
and/or deterioration.
INSTALLATION
(1) Before installing piston and connecting rod
assemblies into the bore, install the piston rings(Re-
fer to 9 - ENGINE/ENGINE BLOCK/PISTON RINGS
- STANDARD PROCEDURE).
(2) Immerse the piston head and rings in clean
engine oil. Position a ring compressor over the piston
and rings. Tighten ring compressor.Ensure posi-
tion of rings do not change during this opera-
tion.
(3) Position bearing onto connecting rod. Lubricate
bearing surface with clean engine oil.
(4) Install Special Tool 8507 Connecting Rod
Guides into connecting rod bolt threads.
(5) The pistons are marked on the piston pin bore
surface with an raised ªFº or arrow on top of piston
indicating installation position. This mark must be
pointing toward the front of engine on both cylinder
banks.
(6) Wipe cylinder bore clean and lubricate with
engine oil.
(7) Rotate crankshaft until connecting rod journal
is on the center of cylinder bore. Insert rod and pis-
ton into cylinder bore and carefully position connect-
ing rod guides over crankshaft journal.
(8) Tap piston down in cylinder bore using a ham-
mer handle. While at the same time, guide connect-
ing rod into position on rod journal.
CAUTION: Connecting Rod Bolts are Torque to
Yield Bolts and Must Not Be Reused. Always
replace the Rod Bolts whenever they are loosened
or removed.
(9) Lubricate rod bolts and bearing surfaces with
engine oil. Install connecting rod cap and bearing.
Tighten bolts to 21 N´m (15 ft. lbs.) plus a 90É turn.
(10) Install the following components:
²Cylinder head(s). (Refer to 9 - ENGINE/CYLIN-
DER HEAD - INSTALLATION).²Cylinder head covers (Refer to 9 - ENGINE/
CYLINDER HEAD/CYLINDER HEAD COVER(S) -
INSTALLATION).
²Install the intake manifold.
²Oil pan and gasket/windage tray. (Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
(11) Fill crankcase with proper engine oil to cor-
rect level.
(12) Connect negative cable to battery.
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING
Before reinstalling used rings or installing new
rings, the ring clearances must be checked.
(1) Wipe the cylinder bore clean.
(2) Insert the ring in the cylinder bore.
NOTE: The ring gap measurement must be made
with the ring positioned at least 12mm (0.50 inch.)
from bottom of cylinder bore.
(3) Using a piston, to ensure that the ring is
squared in the cylinder bore, slide the ring downward
into the cylinder.
(4) Using a feeler gauge check the ring end gap
(Fig. 13). Replace any rings not within specification.
PISTON RING SIDE CLEARANCE
NOTE: Make sure the piston ring grooves are clean
and free of nicks and burrs.
Fig. 13 Ring
1 - FEELER GAUGE
DRENGINE - 5.7L 9 - 213
PISTON & CONNECTING ROD (Continued)

(8) Torque the (3) bolts that attach the front axle
to the left engine bracket to 101 N´m (75 ft. lbs.).
(9) Install the engine oil filter, if removed.
(10) Install the front crossmember(Refer to 13 -
FRAME & BUMPERS/FRAME/FRONT CROSS-
MEMBER - INSTALLATION).
(11) Install the skid plate.
(12) Lower the vehicle.
(13) Reconnect the negative battery cable.
REAR MOUNT
REMOVAL
(1) Raise the vehicle on a hoist.
(2) Using a suitable jack, support transmission.
(3) Remove the nuts from the transmission mount
(Fig. 26).
(4) Remove the two bolts that attach the transmis-
sion mount to the engine bracket.
(5) Raise the transmission enough to remove the
mount from the crossmember.
(6) Remove the mount.
INSTALLATION
NOTE: Threadlocking compound must be applied to
the bolts before installation.(1) Install the two bolts that attach the transmis-
sion mount to the transmission bracket.
(2) Torque the bolts to 61N´m (45 ft.lbs.) torque.
(3) Lower the transmission so the transmission
mount rests on the crossmember, and the studs of
the transmission mount are aligned in the slots in
the crossmember.
(4) Install the nuts onto the transmission mount
studs through the crossmember access slot.
(5) Torque the nuts to 54N´m (40 ft. lbs.).
LUBRICATION
DESCRIPTION
The lubrication system (Fig. 27) is a full flow fil-
tration pressure feed type.
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CHECKING
ENGINE OIL PRESSURE
(1) Remove oil pressure sending unit and install
gauge assembly C-3292.
(2) Run engine until thermostat opens.
(3) Oil Pressure:
²Curb Idle±25 kPa (4 psi) minimum
²3000 rpm±170 - 758 kPa (25 - 110 psi)
(4) If oil pressure is 0 at idle, shut off engine.
Check for a clogged oil pick-up screen or a pressure
relief valve stuck open.
DIAGNOSIS AND TESTING - ENGINE OIL LEAK
Begin with a thorough visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
make sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24 km (15 miles), and
repeat inspection.If the oil leak source is not pos-
itively identified at this time, proceed with the air
leak detection test method.
Fig. 26 TRANSMISSION MOUNT
1 - MOUNT
2 - CROSSMEMBER
3 - NUT
4 - BOLT
9 - 220 ENGINE - 5.7LDR
FRONT MOUNT (Continued)

If the leakage occurs at the crankshaft rear oil seal
area:
(1) Disconnect the battery.
(2) Raise the vehicle.
(3) Remove torque converter or clutch housing
cover and inspect rear of block for evidence of oil.
Use a black light to check for the oil leak:
(a) Circular spray pattern generally indicates
seal leakage or crankshaft damage.
(b) Where leakage tends to run straight down,
possible causes are a porous block, distributor seal,
camshaft bore cup plugs oil galley pipe plugs, oil
filter runoff, and main bearing cap to cylinder
block mating surfaces.
(4) If no leaks are detected, pressurize the crank-
case as outlined in the, Inspection (Engine oil Leaks
in general)
CAUTION: Do not exceed 20.6 kPa (3 psi).
(5) If the leak is not detected, very slowly turn the
crankshaft and watch for leakage. If a leak is
detected between the crankshaft and seal while
slowly turning the crankshaft, it is possible the
crankshaft seal surface is damaged. The seal area on
the crankshaft could have minor nicks or scratches
that can be polished out with emery cloth.
CAUTION: Use extreme caution when crankshaft
polishing is necessary to remove minor nicks and
scratches. The crankshaft seal flange is especially
machined to complement the function of the rear oil
seal.
(6) For bubbles that remain steady with shaft
rotation, no further inspection can be done until dis-
assembled.
OIL
STANDARD PROCEDURE - ENGINE OIL
SERVICE
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase
lubricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
Use an engine oil that is API Service Grade Certi-
fied. MOPARtprovides engine oils that conform to
this service grade.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. Use only engine oils with multi-
ple viscosities such as 5W-30 in the 5.7L engines.
These are specified with a dual SAE viscosity grade
which indicates the cold-to-hot temperature viscosity
range. Select an engine oil that is best suited to your
particular temperature range and variation.
ENERGY CONSERVING OIL
An Energy Conserving type oil is recommended for
gasoline engines. The designation of ENERGY CON-
SERVING is located on the label of an engine oil con-
tainer.
CONTAINER IDENTIFICATION
Standard engine oil identification notations have
been adopted to aid in the proper selection of engine
oil. The identifying notations are located on the label
of engine oil plastic bottles and the top of engine oil
cans (Fig. 28).
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the left
hand of the engine on the 5.7L engines.
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
pressure loss or oil foaming can result.
Inspect engine oil level approximately every 800
kilometers (500 miles). Unless the engine has exhib-
ited loss of oil pressure, run the engine for about ten
Fig. 28 API SYMBOL
9 - 222 ENGINE - 5.7LDR
LUBRICATION (Continued)

minutes before checking oil level. Checking engine oil
level on a cold engine is not accurate.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
(2) With engine OFF, allow approximately five
minutes for oil to settle to bottom of crankcase,
remove engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
(6) Add oil only if level is below the ADD mark on
dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals
described in Maintenance Schedules(Refer to LUBRI-
CATION & MAINTENANCE/MAINTENANCE
SCHEDULES - DESCRIPTION).
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Hoist and support vehicle on safety stands.
(3) Remove oil fill cap.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan. Inspect drain plug threads for
stretching or other damage. Replace drain plug if
damaged.
(6) Install drain plug in crankcase. Torque to 34
N´m ( 25 ft. lbs.).
(7) Lower vehicle and fill crankcase with specified
type and amount of engine oil described in this sec-
tion.
(8) Install oil fill cap.
(9) Start engine and inspect for leaks.
(10) Stop engine and inspect oil level.
USED ENGINE OIL DISPOSAL
Care should be exercised when disposing used
engine oil after it has been drained from a vehicle
engine. Refer to the WARNING at beginning of this
section.
OIL FILTER
REMOVAL
All engines are equipped with a high quality full-
flow, disposable type oil filter. DaimlerChrysler Cor-
poration recommends a Mopartor equivalent oil
filter be used.
(1) Position a drain pan under the oil filter.
(2) Using a suitable oil filter wrench loosen filter.
(3) Rotate the oil filter counterclockwise to remove
it from the cylinder block oil filter boss.
(4) When filter separates from cylinder block oil
filter boss, tip gasket end upward to minimize oil
spill. Remove filter from vehicle.
NOTE: Make sure filter gasket was removed with fil-
ter.
(5) With a wiping cloth, clean the gasket sealing
surface of oil and grime.
INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 29) hand
tighten filter one half turn, or 180É,do not over
tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
Fig. 29 Oil Filter Sealing Surface - Typical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTER
DRENGINE - 5.7L 9 - 223
OIL (Continued)

OIL PAN
REMOVAL
(1) Disconnect the negative battery cable.
(2) Install engine support fixture special tool #
8534.Do not raise engine at this time.
(3) Loosen both left and right side engine mount
through bolts. Do not remove bolts.
(4) Remove the structural dust cover, if equipped.
(5) Drain engine oil.
(6) Remove the front crossmember(Refer to 13 -
FRAME & BUMPERS/FRAME/FRONT CROSS-
MEMBER - REMOVAL).
CAUTION: Only raise the engine enough to provide
clearance for oil pan removal. Check for proper
clearance at fan shroud to fan and cowl to intake
manifold.
(7) Raise engine using special tool # 8534 to pro-
vide clearance to remove oil pan.
NOTE: Do not pry on oil pan or oil pan gasket. Gas-
ket is integral to engine windage tray and does not
come out with oil pan.
(8) Remove the oil pan mounting bolts and oil pan.
NOTE: The double ended oil pan studs must be
installed in the same location that they were
removed from.
(9) Unbolt oil pump pickup tube and remove tube.
(10) Inspect the integral windage tray and gasket
and replace as needed.
INSTALLATION
(1) Clean the oil pan gasket mating surface of the
block and oil pan.
(2) Inspect the integral windage tray and gasket
and replace as needed.
(3) Reinstall the oil pump pickup tube with new
o-ring. Tighten tube to pump fasteners to 28 N´m
(250 in. lbs.).
NOTE: The double ended oil pan studs must be
installed in the same location that they were
removed from.
(4) Position the oil pan and install the mounting
bolts and studs.. Tighten the mounting bolts to 12
N´m (105 in.lbs.).
(5) Lower the engine into mounts using special
tool # 8534.
(6) Install both the left and right side engine
mount through bolts. Tighten the nuts to 68 N´m (50
ft. lbs.).(7) Remove special tool # 8534.
(8) Install structural dust cover, if equipped.
(9) Install the front crossmember(Refer to 13 -
FRAME & BUMPERS/FRAME/FRONT CROSS-
MEMBER - INSTALLATION).
(10) Fill engine oil.
(11) Reconnect the negative battery cable.
(12) Start engine and check for leaks.
OIL PUMP
REMOVAL
(1) Remove the oil pan and pick-up tube(Refer to 9
- ENGINE/LUBRICATION/OIL PAN - REMOVAL).
(2) Remove the timing chain cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(3) Remove the four bolts, and the oil pump.
CLEANING
(1) Wash all parts in a suitable solvent.
INSPECTION
CAUTION: Oil pump pressure relief valve and
spring should not be removed from the oil pump. If
these components are disassembled and or
removed from the pump the entire oil pump assem-
bly must be replaced.
(1) Remove the pump cover.
(2) Clean all parts thoroughly. Mating surface of
the oil pump housing should be smooth. If the pump
cover is scratched or grooved the oil pump assembly
should be replaced.
(3) Slide outer rotor into the body of the oil pump.
Press the outer rotor to one side of the oil pump body
and measure clearance between the outer rotor and
the body (Fig. 30). If the measurement is 0.235mm
(0.009 in.) or more the oil pump assembly must be
replaced.
(4) Install the inner rotor in the into the oil pump
body. Measure the clearance between the inner and
outer rotors (Fig. 31). If the clearance between the
rotors is .150 mm (0.006 in.) or more the oil pump
assembly must be replaced.
(5) Place a straight edge across the body of the oil
pump (between the bolt holes), if a feeler gauge of
.095 mm (0.0038 in.) or greater can be inserted
between the straightedge and the rotors, the pump
must be replaced (Fig. 32).
(6) Reinstall the pump cover. Torque fasteners to
15 N´m (132 in. lbs.).
9 - 224 ENGINE - 5.7LDR

TIMING/CHAIN AND
SPROCKETS
REMOVAL
(1) Disconnect battery negative cable.
(2) Drain cooling system.
(3) Remove Timing Chain Cover.
CAUTION: The camshaft pin and the slot in the cam
sprocket must be clocked at 12:00. The crankshaft
keyway must be clocked at 2:00. The crankshaft
sprocket must be installed so that the dots and or
paint marking is at 6:00.
(4) Re-install the vibration damper bolt finger
tight. Using a suitable socket and breaker bar, rotate
the crankshaft to align timing chain sprockets and
keyways as shown (Fig. 33).
(5) Retract tensioner shoe until hole in shoe lines
up with hole in bracket. Slide a suitable pin into the
holes.
(6) Remove camshaft sprocket attaching bolt and
remove timing chain with crankshaft and camshaft
sprockets.
(7) If tensioner assembly is to be replaced, remove
the tensioner to block bolts and remove tensioner
assembly.
INSTALLATION
(1) If tensioner assembly is being replaced, install
tensioner and mounting bolts. Torque bolts to 28 N´m
(250 in. lbs.).
(2) Retract tensioner if required.
CAUTION: The camshaft pin and the slot in the cam
sprocket must be clocked at 12:00. The crankshaft
keyway must be clocked at 2:00. The crankshaft
sprocket must be installed so that the dots and or
paint marking is at 6:00.
(3) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on exact
imaginary center line through both camshaft and
crankshaft bores (Fig. 34).
CAUTION: The timing chain must be installed with
the single plated link aligned with the dot and or
paint marking on the camshaft sprocket. The crank-
shaft sprocket is aligned with the dot and or paint
marking on the sprocket between two plated timing
chain links.
(4) Place timing chain around both sprockets (Fig.
34).
(5) Lift sprockets and chain (keep sprockets tight
against the chain in position as shown).
(6) Slide both sprockets evenly over their respec-
tive shafts and check alignment of timing marks.
Fig. 33 5.7L TIMING MARK ALIGNMENT
1 - Chain Tensioner
2 - Camshaft Sprocket
3 - Crankshaft Sprocket
Fig. 34 5.7L TIMING MARK ALIGNMENT
1 - Chain Tensioner
2 - Camshaft Sprocket
3 - Crankshaft Sprocket
9 - 228 ENGINE - 5.7LDR

(7) Install the camshaft bolt. Tighten the bolt to
122 N´m (90 ft. lbs.) torque.
(8)Remove tensioner pin.Again, verify align-
ment of timing marks.
(9) Install the oil pump(Refer to 9 - ENGINE/LU-
BRICATION/OIL PUMP - INSTALLATION).
(10) Install the oil pan and pick up(Refer to 9 -
ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
(11) Install the timing chain cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(12) Fill cooling system(Refer to 7 - COOLING -
STANDARD PROCEDURE).
(13) Connect battery negative cable.
(14) Start engine and check for oil and coolant
leaks.TIMING CHAIN/TENSIONER
DESCRIPTION
The timing chain tensioner is a stamped steel con-
stant tension mechanical design. It is mounted to the
front of the engine, behind the timing chain drive.
OPERATION
The timing chain tension is maintained by routing
the timing chain through the tensioner assembly. A
nylon covered spring steel arm presses on the timing
chain maintaining the correct chain tension.
DRENGINE - 5.7L 9 - 229
TIMING/CHAIN AND SPROCKETS (Continued)