2003 DODGE RAM engine

REFACING VALVES AND VALVE SEATS
The intake and exhaust valves have a 45É face
angle and a 45É to 44 1/2É seat angle (Fig. 16).
VALVE FACE AND SEAT ANGLES CHART
ITEM DESCRIPTION SPECIFICATION
ASEAT WIDTH 1.016 - 1.524
mm
INTAKE (0.040 - 0.060
in.)
SEAT WIDTH 1.016 - 1.524
mm
EXHAUST (0.040 - 0.060
in.)
BFACE ANGLE
(INT. and EXT.) 45É
CSEAT ANGLE
(INT. and EXT.) 44
1¤2É
DCONTACT
SURFACE Ð
VALVES
Inspect the remaining margin after the valves are
refaced (Fig. 17). Valves with less than 1.190 mm
(0.047 inch) margin should be discarded.
VALVE SEATS
(1) When refacing valve seats, it is important that
the correct size valve guide pilot be used for reseat-
ing stones. A true and complete surface must be
obtained.(2) Measure the concentricity of valve seat using a
dial indicator. Total runout should not exceed 0.038
mm (0.0015 inch) total indicator reading.
(3) Inspect the valve seat with Prussian blue to
determine where the valve contacts the seat. To do
this, coat valve seat LIGHTLY with Prussian blue
then set valve in place. Rotate the valve with light
pressure. If the blue is transferred to the center of
valve face, contact is satisfactory. If the blue is trans-
ferred to the top edge of valve face, lower valve seat
with a 15É stone. If the blue is transferred to bottom
edge of valve face raise valve seat with a 60É stone.
(4) When seat is properly positioned the width of
valve seats should be 1.016-1.524 mm (0.040-0.060
inch).
VALVE SPRING INSPECTION
Whenever valves have been removed for inspection,
reconditioning or replacement, valve springs should
be tested. As an example the compression length of
the spring to be tested is 1-5/16 inch. Turn table of
Universal Valve Spring Tester Tool until surface is in
line with the 1-5/16 inch mark on the threaded stud.
Be sure the zero mark is to the front (Fig. 18). Place
spring over stud on the table and lift compressing
lever to set tone device. Pull on torque wrench until
ping is heard. Take reading on torque wrench at this
instant. Multiply this reading by 2. This will give the
spring load at test length. Fractional measurements
are indicated on the table for finer adjustments.
Refer to specifications to obtain specified height and
allowable tensions. Discard the springs that do not
meet specifications.
Fig. 16 Valve Face and Seat Angles
1 - CONTACT POINT
Fig. 17 Intake and Exhaust Valves
1 - MARGIN
2 - VALVE SPRING RETAINER LOCK GROOVE
3 - STEM
4-FACE
9 - 376 ENGINE 8.0LDR
INTAKE/EXHAUST VALVES & SEATS (Continued)

REMOVAL
REMOVALÐVALVE STEM SEALS
NOTE: This procedure is done with the cylinder
head installed.
(1) Disconnect the negative cable from the battery.
(2) Set engine basic timing to Top Dead Center
(TDC) and remove air cleaner.
(3) Remove cylinder head covers (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL) and spark plugs (Refer to 8
- ELECTRICAL/IGNITION CONTROL/SPARK
PLUG - REMOVAL).
(4) Using suitable socket and flex handle at crank-
shaft retaining bolt, turn engine so that the piston of
the cylinder to be worked on, is at TDC on the com-
pression stroke.
(5) Remove rocker arms (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARM / ADJUSTER
ASSY - REMOVAL).
(6) With air hose attached to an adapter installed
in the spark plug hole, apply 620-689 kPa (90-100
psi) air pressure.
(7) Using Valve Spring Compressor Tool
MD-998772A with adapter 6716A (Fig. 19), compress
valve spring and remove retainer valve locks and
valve spring.
(8) Remove the valve stem seal.
REMOVALÐVALVES AND VALVE SPRINGS
(1) Remove the cylinder head (Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(2) Special studs must be used to adapt the Valve
Spring Compressor Tool to the V-10 cylinder head
(Fig. 20). Install the metric end into the Special Tool
MD998772A and the 5/16 end into the cylinder head.
Fig. 18 Testing Valve Spring for Compressed
1 - TORQUE WRENCH
2 - VALVE SPRING TESTER
Fig. 19 Valve Spring Compressor MD-998772A with
Adaptor 6716-A and Screw 6765
1 - SPECIAL TOOL MD 998772A
2 - SPECIAL TOOL 6765
3 - SPECIAL TOOL 6716A
4 - AIR HOSE
Fig. 20 Special Studs 6715 for V-10 Engine
1 - SPECIAL TOOL 6715
DRENGINE 8.0L 9 - 377
INTAKE/EXHAUST VALVES & SEATS (Continued)

(3) Compress valve springs using Valve Spring
Compressor Tool MD-998772A with Adapter 6716A
and Screw 6765 (Fig. 21). Tap the retainer using a
brass drift and ball peen hammer to loosen locks
away from retainer.
(4) Remove valve retaining locks, valve spring
retainers and valve springs. Check for abnormal
wear, replace as required.
(5) Remove the valve stem seals.
(6) Before removing valves, remove any burrs from
valve stem lock grooves to prevent damage to the
valve guides. Identify valves to ensure installation in
original location.
CLEANING
Clean valves thoroughly. Discard burned, warped,
or cracked valves.
Remove carbon and varnish deposits from inside of
valve guides with a reliable guide cleaner.
INSPECTION
Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 in.), replace the valve.
Measure valve stem guide clearance as follows:
(1) Install Valve Guide Sleeve Tool C-3973 over
valve stem and install valve (Fig. 22). The special
sleeve places the valve at the correct height for
checking with a dial indicator.
(2) Attach dial indicator Tool C-3339 to cylinder
head and set it at right angles to valve stem being
measured (Fig. 23).
(3) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 in.). Ream the guides for valves with oversizestems if dial indicator reading is excessive or if the
stems are scuffed or scored.
INSTALLATION
INSTALLATIONÐVALVE STEM SEAL
(1) Install new seal onto valve stem.
(2) Position valve spring onto valve stem.
(3) Position Valve Spring Compressor with Adapter
Studs onto cylinder head
(4) Compress valve spring and install retainer
valve locks.
(5) Remove air hose and adapter from spark plug
hole.
(6) Remove Valve Spring Compressor and Adapter
Studs.
(7) Install rocker arms (Refer to 9 - ENGINE/CYL-
INDER HEAD/ROCKER ARM / ADJUSTER ASSY -
INSTALLATION).
Fig. 21 Valve Spring Compressor MD-998772A with
Adaptor 6716-A and Screw 6765
1 - SPECIAL TOOL MD 998772A
2 - SPECIAL TOOL 6765
3 - SPECIAL TOOL 6716A
4 - AIR HOSE
Fig. 22 Positioning Valve with Tool C-3973
1 - VALVE
2 - SPACER TOOL
Fig. 23 Measuring Valve Guide Wear
1 - VALVE
2 - SPECIAL TOOL C-3339
9 - 378 ENGINE 8.0LDR
INTAKE/EXHAUST VALVES & SEATS (Continued)

(8) The cylinder head cover gasket can be used
again. Install the gasket onto the head rail.For the
left side the number tab is at the front of
engine with the number up. For the right side
the number tab is at the rear of engine with the
number up.
CAUTION: The cylinder head cover fasteners have a
special plating. DO NOT use alternative fasteners.
(9) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION) (Fig. 24).
(10) Install closed crankcase ventilation system.
(11) Connect the evaporation control system.
(12) Install air cleaner.
(13) Connect the negative cable to the battery.
(14) Road test vehicle and check for leaks.
INSTALLATIONÐVALVES AND VALVE SPRINGS
(1) Clean valves thoroughly. Discard burned,
warped and cracked valves.(2) Remove carbon and varnish deposits from
inside of valve guides with a reliable guide cleaner.
(3) Measure valve stems for wear. If wear exceeds
0.051 mm (0.002 inch), replace the valve.
(4) Make sure there are no burrs on valve stems.
(5) Coat valve stems with lubrication oil. Insert
valves into valve guides in cylinder head.
(6) Install new seals on all valve guides(BLACK
on intake and BROWN on exhaust). Install valve
springs and valve retainers.
(7) Compress valve springs with Valve Spring
Compressor Tool MD-998772A and adapter 6716A,
install locks and release tool. Tap the retainer with a
brass or heavy plastic hammer to ensure locks have
been seated.
(8) If valves and/or seats were ground, measure
the installed height of springs. Make sure the mea-
surement is taken from bottom of spring seat in cyl-
inder head to the bottom surface of spring retainer. If
spacers are installed, measure from the top of spacer.
If height is greater than 42.86 mm (1-11/16 inches),
install a 1.587 mm (1/16 inch) spacer in head coun-
terbore. Ensure this brings spring height back to nor-
mal, 41.27 to 42.86 mm (1-5/8 to 1-11/16 inch).
(9) Install the cylinder head (Refer to 9 - ENGINE/
CYLINDER HEAD - INSTALLATION).
ROCKER ARM / ADJUSTER
ASSY
REMOVAL
(1) Disconnect spark plug wires by pulling the boot
straight out in line with plug.
(2) Remove cylinder head cover and gasket (Refer
to 9 - ENGINE/CYLINDER HEAD/CYLINDER
HEAD COVER(S) - REMOVAL).
(3) Remove the rocker arm bolts and the rocker
arm assembly (Fig. 25). Place rocker arm assemblies
on a bench in the same order as removed.
(4) Remove the push rods and place them on a
bench in the same order as removed.
INSTALLATION
CAUTION: DO NOT rotate or crank the engine dur-
ing or immediately after rocker arm installation.
Allow the hydraulic roller tappets adequate time to
bleed down (about 5 minutes).
Fig. 24 Cylinder Head Covers
1 - CYLINDER HEAD COVER
2 - CYLINDER HEAD COVER GASKET
DRENGINE 8.0L 9 - 379
INTAKE/EXHAUST VALVES & SEATS (Continued)

(1) Install the push rods in the same order as
removed.
(2) Install rocker arm assemblies in the same
order as removed. Tighten the rocker arm bolts to 53
N´m (40 ft. lbs.) torque.
(3) Install cylinder head cover and gasket (Refer to
9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(4) Connect spark plug wires.
ENGINE BLOCK
CLEANING
Clean cylinder block thoroughly and check all core
hole plugs for evidence of leaking.
INSPECTION
Examine block for cracks or fractures.
The cylinder walls should be checked for out-of-
round and taper with Cylinder Bore Indicator Tool,
Special tool 6879 or equivalent. The cylinder block
should be bored and honed with new pistons and
rings fitted if:
²The cylinder bores show more than 0.127 mm
(0.005 inch) out-of-round.
²The cylinder bores show a taper of more than
0.254 mm (0.010 inch).
²The cylinder walls are badly scuffed or scored.
Boring and honing operation should be closely coor-
dinated with the fitting of pistons and rings so spec-
ified clearances may be maintained.
CAMSHAFT & BEARINGS (IN
BLOCK)
REMOVAL
REMOVALÐCAMSHAFT BEARINGS
This procedure requires that the engine is removed
from the vehicle.
(1) With engine completely disassembled, drive out
rear cam bearing core hole plug.
NOTE: It is not advisable to attempt to replace cam-
shaft bearings unless special removal and installa-
tion tools are available, such as recommended tool
8544 Camshaft Bushing Remover Installer.
(2) Using recommended tool 8544 Camshaft Bush-
ing Remover Installer, Drive out bearing shells.
REMOVALÐCAMSHAFT
(1) Remove rocker arms and push rods (Refer to 9
- ENGINE/CYLINDER HEAD/ROCKER ARM /
ADJUSTER ASSY - REMOVAL). Identify each part
so it can be installed in its original location.
NOTE: The 4 corner tappets can not be removed
without removing the cylinder heads and gaskets.
However, they can be lifted and retained for cam-
shaft removal.
(2) Remove the Bolts retaining the yoke retaining
spider. Remove the yoke retaining spider, tappet
aligning yokes and tappets.
(3) Remove upper and lower intake manifolds
(Refer to 9 - ENGINE/MANIFOLDS/INTAKE MANI-
FOLD - REMOVAL).
(4) Remove timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL) and timing chain and
sprockets (Refer to 9 - ENGINE/VALVE TIMING/
TIMING BELT/CHAIN AND SPROCKETS -
REMOVAL).
Fig. 25 Rocker Arm - Typical
1 - ROCKER ARMS
2 - ROCKER ARM PEDESTALS
3 - RETAINER
9 - 380 ENGINE 8.0LDR
ROCKER ARM / ADJUSTER ASSY (Continued)

(5) Remove camshaft thrust plate (Fig. 26).
(6) Install a long bolt into front of camshaft to aid
in removal of the camshaft. Remove camshaft, being
careful not to damage cam bearings with the cam
lobes.
INSTALLATION
INSTALLATIONÐCAMSHAFT BEARINGS
(1) Install new camshaft bearings using recom-
mended Tool 8544 Camshaft Bushing Remover
Installer, by sliding the new camshaft bearing shell
over proper adapter.
(2) Bearings must be carefully aligned to bring oil
holes into full register with oil passages from the
main bearing. If the camshaft bearing shell oil holes
are not in exact alignment, remove and install them
correctly. Install a new core hole plug at the rear of
camshaft.Be sure this plug does not leak.
INSTALLATIONÐCAMSHAFT
(1) Lubricate camshaft lobes and camshaft bearing
journals. Using a long bolt, insert the camshaft into
the cylinder block.
NOTE: Whenever an engine has been rebuilt, a new
camshaft and/or new tappets installed, add 1 pint of
MoparTCrankcase Conditioner, or equivalent. The
oil mixture should be left in engine for a minimum
of 805 km (500 miles). Drain at the next normal oil
change.
(2) Install camshaft thrust plate. Tighten the torx
bolts to 22 N´m (16 ft. lbs.) torque.
(3) Check camshaft end play. The end play should
be 0.051-0.152 mm (0.002-0.006 inch) with a new
thrust plate and up to 0.254 mm (0.010 inch) with a
used thrust plate. If not within these limits install a
new thrust plate.(4) Line up key with keyway in sprocket, then
using Special Tools C-3688, C-3718 and MB990799
install crankshaft timing sprocket. Make sure the
sprocket seats against the crankshaft shoulder (Fig.
27).
(5) Install timing chain and sprocket (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT/CHAIN
AND SPROCKETS - INSTALLATION).
(6) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(7) Install the crankshaft pulley/damper (Refer to
9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - INSTALLATION).
(8) Prime oil pump by squirting oil in the oil filter
mounting hole and filling the J-trap of the front tim-
ing cover. When oil is running out, install oil filter
that has been filled with oil.
(9) Each tappet reused must be installed in the
same position from which it was removed.When
camshaft is replaced, all of the tappets must be
replaced.
(10) Install tappets and push rods in their original
location.
(11) Position the tappet aligning yokes and yoke
retaing spider.
(12) Install the retaining spider mounting bolts.
Tighten bolts to 22 N´m (16 ft. lbs.).
Fig. 26 Camshaft
1 - CAMSHAFT
2 - THRUST PLATE
Fig. 27 Crankshaft Sprocket Installation
1 - SPECIAL TOOL C-3688
2 - SPECIAL TOOL C-3718
3 - SPECIAL TOOL MD990799
DRENGINE 8.0L 9 - 381
CAMSHAFT & BEARINGS (IN BLOCK) (Continued)

(13) Install the rocker arms (Refer to 9 - ENGINE/
CYLINDER HEAD/ROCKER ARM / ADJUSTER
ASSY - INSTALLATION).
(14) The cylinder head cover gasket can be used
again. Install the gasket onto the head rail.For the
left side the number tab is at the front of
engine with the number up. For the right side
the number tab is at the rear of engine with the
number up.
CAUTION: The cylinder head cover fasteners have a
special plating. DO NOT use alternative fasteners.
(15) Install cylinder head cover (Fig. 28) (Refer to
9 - ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(16) Install the intake manifolds (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(17) Start engine and check for leaks.CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING ROD
BEARING FITTING
Fit all rods on a bank until completed. DO NOT
alternate from one bank to another, because connect-
ing rods and pistons are not interchangeable from
one bank to another.
The bearing caps are not interchangeable and
should be marked at removal to ensure correct
assembly.
Each bearing cap has a small V-groove across the
parting face. When installing the lower bearing shell,
be certain that the V-groove in the shell is in line
with the V-groove in the cap. This provides lubrica-
tion of the cylinder wall in the opposite bank.
The bearing shells must be installed so that the
tangs are in the machined grooves in the rods and
caps.
Limits of taper or out-of-round on any crankshaft
journals should be held to 0.025 mm (0.001 in.).
Bearings are available in 0.025 mm (0.001 in.), 0.051
mm (0.002 in.), 0.076 mm (0.003 in.), 0.254 mm
(0.010 in.) and 0.305 mm (0.012 in.) undersize.
Install the bearings in pairs. DO NOT use a new
bearing half with an old bearing half. DO NOT
file the rods or bearing caps.
CRANKSHAFT
REMOVAL
When a crankshaft is replaced, all main and con-
necting rod bearings should be replaced with new
bearings. Therefore, selective fitting of the bearings
is not required when a crankshaft and bearings are
replaced.
(1) Remove the oil pan and oil pickup tube (refer
to Oil Pan in this section for correct procedure).
(2) Remove the timing chain cover and gasket.
Remove and discard the front crankshaft oil seal and
cover gasket.
(3) Remove Transmission (refer to Group 21,
Transmission).
(4) Remove the rear seal retainer (refer to Crank-
shaft Rear Seal Retainer in this section for correct
procedure).
(5) Identify main bearing caps before removal (Fig.
29). Remove bearing caps and lower bearings one at
a time.
(6) Remove the connecting rod bearing caps.
(7) Lift the crankshaft straight out of the block.
(8) Remove the upper main bearings from the
block.
Fig. 28 Cylinder Head Cover
1 - CYLINDER HEAD COVER
2 - CYLINDER HEAD COVER GASKET
9 - 382 ENGINE 8.0LDR
CAMSHAFT & BEARINGS (IN BLOCK) (Continued)

INSTALLATION
When a crankshaft is replaced, all main and con-
necting rod bearings should be replaced with new
bearings. Therefore, selective fitting of the bearings
is not required when a crankshaft and bearings are
replaced.
NOTE: Lubricate crankshaft main bearings with
clean engine oil.
(1) Position upper main bearings into block.
(2) Position the crankshaft into the cylinder block.
(3) Lubricate the main journals with clean engine
oil. Install upper main bearings, caps and bolts. Fol-
low the 2 step tightening sequence, starting with
main bearing cap 1.
(4) Lubricate the connecting rod bearings and jour-
nals with clean engine oil. Carefully install connect-
ing rods to the crankshaft.
(5) Using Special Tool 8359 Seal Installer install
new oil into oil seal retainer.
(6) Using Special Tool 6687 Guide, install the rear
seal retainer with a new gasket.
(7) Install the timing chain cover with a new gas-
ket and oil seal.
(8) Prime oil pump by squirt oil in the oil filter
mounting hole and filling the J-trap of the front tim-
ing cover. When oil is running out, install oil filter
that has been filled with oil.(9) Apply a rearward axial load of 667 N (150
lbs-f) on crankshaft centerline, driving No.3 main cap
and thrust bearing against No.3 bulkhead. Repeat
procedure, driving crankshaft forward to align rear
flange of thrust bearings in a common plane. Front
face of No.1 main cap must not extend forward in
front of face of No.1 bulkhead.
(10) Install the oil pickup tube. Tighten the bolts
to 16 N´m (144 in. lbs.) torque.
(11) Install the oil pan.
CRANKSHAFT MAIN
BEARINGS
STANDARD PROCEDUREÐFITTING
CRANKSHAFT MAIN BEARINGS
Bearing caps are not interchangeable and should
be marked at removal to ensure correct assembly.
Upper and lower bearing halves are NOT inter-
changeable. All lower main bearing halves are inter-
changeable. Upper main bearing halves of No. 2, 4,
and 5 are interchangeable. Upper main bearing
halves of No. 1 and 6 are interchangeable, this also
applies to the lower bearing halves.
The No.3 main bearing is flanged to carry the
crankshaft thrust loads. This bearing is NOT inter-
changeable with any other bearing halves in the
engine. Bearing shells are available in standard and
the following undersizes: 0.25 mm (0.001 inch), 0.051
mm (0.002 inch), 0.076 mm (0.003 inch), 0.254 mm
(0.010 inch) and 0.305 mm (0.012 inch). Never install
an undersize bearing that will reduce clearance
below specifications.
REMOVAL
(1) Remove the oil pan and oil pump pick-up tube
(Refer to 9 - ENGINE/LUBRICATION/OIL PAN -
REMOVAL).
(2) Identify bearing caps before removal. Remove
bearing caps one at a time.
(3) Remove upper half of bearing by inserting
Crankshaft Main Bearing Remover/Installer Tool
C-3059 into the oil hole of crankshaft (Fig. 30).
(4) Slowly rotate crankshaft clockwise, forcing out
upper half of bearing shell.
INSTALLATION
Only one main bearing should be selectively fitted
while all other main bearing caps are properly tight-
ened. All bearing capbolts removed during service
procedures are to be cleaned and oiled before instal-
lation.
When installing a new upper bearing shell, slightly
chamfer the sharp edges from the plain side.
Fig. 29 Main Bearing Identification
1 - MAIN BEARING CAP
2 - UPPER MAIN BEARINGS
3 - CRANKSHAFT
4 - LOWER MAIN BEARINGS
DRENGINE 8.0L 9 - 383
CRANKSHAFT (Continued)