
DESCRIPTION SPECIFICATION
CONNECTING RODS
Piston Pin bore Diameter 24.940 ± 24.978 mm
(0.9819 ± 0.9834 in.)
Side Clearance 0.25 ± 0.46 mm
(0.010 ± 0.018 in.)
Total Weight (Less
Bearing)744 gms. (26.24 oz.)
CRANKSHAFT
Rod Journal Diameter 53.950 ± 53.975 mm
(2.124 ± 2.125 in.)
Out of Round (Max.) 0.0254 mm (0.001 in.)
Taper (Max.) 0.0254 mm (0.001 in.)
Bearing Clearance 0.005 ± 0.074 mm
(0.0002 ± 0.0029 in.)
Service Limit 0.0762 mm (0.003 in.)
Main Bearing Journal
Diameter76.187 ± 76.213 mm
(2.8995 ± 3.0005 in.)
Out of Round (Max.) 0.0254 mm (0.001 in.)
Taper (Max.) 0.0254 mm (0.001 in.)
Bearing Clearance 0.0051 ± 0.058 mm
(0.0002 ± 0.0023 in.)
Service Limit 0.071 mm (0.0028 in.)
End Play 0.076 ± 0.305 mm
(0.003 ± 0.012 in.)
Service LimitÐEnd Play 0.381 mm (0.015 in.)
CYLINDER BLOCK
Cylinder Bore Diameter 101.60 ± 101.65 mm
(4.0003 ± 4.0008 in.)
Out of Round (Max.) 0.0762 mm (0.003 in.)
Taper (Max.) 0.127 mm (0.005 in.)
Lifter Bore Diameter 22.982 ± 23.010 mm
(0.9048 ± 0.9059 in.)DESCRIPTION SPECIFICATION
CYLINDER HEAD AND VALVES
Valve Seat Angle 44.5É
Runout (Max.) 0.0762 mm (0.003 in.)
Width (Finish) ± Intake 1.016 ± 1.524 mm
(0.040 ± 0.060 in.)
Valve Face Angle 45É
Valve Head Diameter
Intake 48.640 ± 48.900 mm
(1.915 ± 1.925 in.)
Exhaust 41.123 ± 41.377 mm
(1.619 ± 1.629 in.)
Overall Length
Intake 145.19 ± 145.82 mm
(5.716 ± 5.741 in.)
Exhaust 145.54 ± 146.18 mm
(5.730 ± 5.755 in.)
Lift (@ zero lash)
Intake 9.91 mm (0.390 in.)
Exhaust 10.34 mm (0.407 in.)
Stem Diameter 7.900 ± 7.920 mm
(0.311 ± 0.312 in.)
Guide Bore 9.500 ± 9.525 mm
(0.374 ± 0.375 on.)
Stem to Guide Clearance 0.025 ± 0.076 mm
(0.001 ± 0..003 in.)
Service Limit ( Runout) 0.4318 (0.017 in.)
Valve Spring Free Length 49.962 mm (1.967 in.)
Spring Tension
Valve Closed 378 N @ 41.66 mm
(85 lbs. @ 1.64 in.)
Valve Open 890 N @ 30.89 mm
(200 lbs. @ 1.212 in.)
Number of Coils 6.8
Installed Height 41.66 mm (1.64 in.)
Wire Diameter 4.50 mm (0.177 in.)
DRENGINE 8.0L 9 - 365
ENGINE 8.0L (Continued)

INTAKE/EXHAUST VALVES &
SEATS
DESCRIPTION
The valves (Fig. 13) are arranged in-line and
inclined 18É. The rocker pivot support and the valve
guides are cast integral with the heads.
STANDARD PROCEDURE
VALVE SERVICE
VALVE GUIDES
Measure valve stem guide clearance as follows:
(1) Install Black Valve Guide Sleeve Tool C-6819
over valve stem for theINTAKEvalve and install
valve (Fig. 14). The special sleeve places the valve at
the correct height for checking with a dial indicator.
(2) Install Silver Valve Guide Sleeve Tool C-6818
over valve stem for theEXHAUSTvalve and install
valve. The special sleeve places the valve at the cor-
rect height for checking with a dial indicator.
(3) Attach Dial Indicator Tool C-3339 to cylinder
head and set it at right angle of valve stem being
measured (Fig. 15).
(4) Move valve to and from the indicator. The total
dial indicator reading should not exceed 0.432 mm
(0.017 inch). Ream the guides for valves with over-
size stems if dial indicator reading is excessive or if
the stems are scuffed or scored.
Service valves with oversize stems are available as
shown below
REAMER SIZE CHART
REAMER O/S VALVE GUIDE SIZE
0.076 mm 8.026 - 8.052 mm
(0.003 in.) (0.316 - 0.317 in.)
0.381 mm 8.331 - 8.357 mm
(0.015 in.) (0.316 - 0.329 in.)
(5) Slowly turn reamer by hand and clean guide
thoroughly before installing new valve.Ream the
valve guides from standard to 0.381 mm (0.015
inch). Use a 2 step procedure so the valve
guides are reamed true in relation to the valve
seat:
²Step 1ÐReam to 0.0763 mm (0.003 inch).
²Step 2ÐReam to 0.381 mm (0.015 inch).
Fig. 13 Intake and Exhaust ValvesÐ8.0L Engine
1 - MARGIN
2 - VALVE SPRING RETAINER LOCK GROOVE
3 - STEM
4-FACE
Fig. 14 Positioning Valve Spacer Tool (Typical)
1 - VALVE
2 - SPACER TOOL
Fig. 15 Measuring Valve Guide Wear
1 - VALVE
2 - SPECIAL TOOL C-3339
DRENGINE 8.0L 9 - 375

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)

(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)

SERVICE SLEEVE ASSEMBLY
NOTE: Two sleeve halves are included with each
kit. Modifications as follow, are necessary to create
the correct sleeve assembly for each application.
(1) On 4X2 models, the9lower9sleeve is made by
cutting off the tab and cutting out a notch in the bot-
tom sleeve portion. Round the corners of the cut out
to keep stress cracks from forming. On 4X4 models
the9lower9sleeve is used as provided. (Fig. 16)
(2) On both 4X2 and 4X4 models cut off the front
tab on the upper sleeve portion. (Fig. 17)(3) The sleeve halves are shipped slightly over-
sized to allow custom fitting to each replacement
frame rail tip. It is necessary to grind the mating
surfaces to achieve the desired snug fit into the
replacement tip (rail tube has increasing height rear-
ward of the cut line). Once the two sleeve halves are
fitted, bevel the edges 25É - 30É.
NOTE: Scribing a line 2 mm from the cut edge and
then grinding back to the mark will simplify the
bevel creation process and accuracy.
(4) Remove any burrs at the beveled edges.
(5) Using the Weld Process Specifications table,
weld the two halves of the repair sleeve together.
(Fig. 18)
(6) Clean the welds of any flux and other impuri-
ties and grind smooth before proceeding with the
installation of the sleeve.
(7) Find the centerline of the sleeve and scribe a
centerline mark. Mark two additional lines 2 mm
(0.08 in.) on either side of the centerline mark to help
ensure the required 4 mm-6mm(0.16 in. - 0.24 in.)
weld root gap. (Fig. 18)
Fig. 16 4X2 LOWER SLEEVE CUT LOCATION
1 - SERVICE SLEEVE LOWER HALF
2 - CUT DIMENSION 27 mm (1.06 in.)
3 - CUT DIMENSION 36.1 mm (1.42 in)
4 - 4X2 CUTOUT
5 - FRONT TAB CUT LINE (4X2 ONLY)
Fig. 17 UPPER SLEEVE CUT LOCATION
1 - SERVICE SLEEVE UPPER HALF
2 - CUT LOCATION
Fig. 18 SERVICE SLEEVE ASSEMBLY
1 - CENTERLINE SCRIBE MARK
2 - WELD SEAM
3 - REAR TAB (4X4 ONLY)
4 - SCRIBE LINE LOCATION 2 mm (0.08 in.)
5 - FRONT TAB (4X4 ONLY)
DRFRAMES & BUMPERS 13 - 11
FRAME (Continued)

CAUTION:
All welds should conform to DaimlerChrysler vehicle engineering process standard ªps 9472º.
WELD PROCESS SPECIFICATIONS
WELDING PROCESS FLUX CORED ARC GAS METAL ARC (MIG)* SHIELDED METAL ARC
(STICK)
Material Thickness3.7 mm to 4.2 mm 3.7 mm to 4.2 mm 3.7 mm to 4.2 mm
Electrode TypeLincoln Electrical Co.
Product #: NR-211 MP
(Do Not Substitute)AWS ER70S-3
(Do Not Substitute)** AWS E 7018
Electrodes Size Inches.045 Tubular .035 Solid 3/329
Electrode Stick Out3/89- 1/291/29- 5/89N/A
PolarityElectrode9-9
Work Piece9+9Electrode9+9
Work Piece9-9Electrode9+9
Work Piece9-9
Shielding GasSelf Shielded 75% Ar
25% CO2Self Shielded
Gas Flow RateN/A 25 - 35 CFM N/A
Wire Feed Speed
(inches per minute)110 - 130 Vertical Down
70 - 90 Flat & Overhead245 - 250 Vertical Down
210 - 225 Flat &
OverheadN/A
Approximate Amperage
Vertical110 - 130 175 85 (3/329Diameter)
Flat & Overhead70 - 90 155 90 (3/329Diameter)
Voltage15-18 19-20 N/A
Direction of Welding
VerticalVertical Down Hill (only) Vertical Down Hill (only) Vertical - Up Hill (only)
Flat & OverheadFlat - Push or Drag Flat - Push or Drag Flat - Drag
*First choice - Gas Metal Arc Welding Process:
Butt joints - apply two layers (passes) of weld metal.
First pass should only fill approximately
1¤2the thick-
ness. Vertical position welds - maintain electrode
wire at leading edge of weld puddle while traveling
down hill to produce maximum penetration into the
sleeve. These techniques work for FCAW as well.
**E7018new electrodes may be exposed to the
atmosphere for up to ten hours with no harmful
effect. Reconditioning schedules should come from
the manufacturer.
SPECIFICATIONS
SPECIFICATIONS - FRAME DIMENSIONS
NOTE: Frame dimensions are listed in metric scale.
All dimensions are from center to center of Princi-
pal Locating Point (PLP), or from center to center of
PLP and fastener location.
VEHICLE PREPARATION
Position the vehicle on a level work surface. Using
screw or bottle jacks, adjust the vehicle PLP heights
to the specified dimension above a level work surface.
Vertical dimensions can be taken from the work sur-
face to the locations indicated were applicable.
INDEX
DESCRIPTION FIGURE
Frame Dimensional Graphics, Side
And Top View24
140.5 In Wheelbase - Heavy Duty -
2 Wheel Drive25
140.5 In Wheelbase - Heavy Duty -
4 Wheel Drive26
160.5 In Wheelbase - Heavy Duty -
2 Wheel Drive27
160.5 In Wheelbase - Heavy Duty -
4 Wheel Drive28
DRFRAMES & BUMPERS 13 - 17
FRAME (Continued)

INSTALLATION
(1) Install fuel injector(s) into fuel rail assembly
and install retaining clip(s).
(2) If same injector(s) is being reinstalled, install
new o-ring(s).
(3) Apply a small amount of clean engine oil to
each injector o-ring. This will aid in installation.
(4) Install fuel rail. Refer to Fuel Rail Installation.
(5) Start engine and check for fuel leaks.
FUEL PUMP RELAY
DESCRIPTION
The 5±pin, 12±volt, fuel pump relay is located in
the Power Distribution Center (PDC). Refer to the
label on the PDC cover for relay location.
OPERATION
The Powertrain Control Module (PCM) energizes
the electric fuel pump through the fuel pump relay.
The fuel pump relay is energized by first applying
battery voltage to it when the ignition key is turned
ON, and then applying a ground signal to the relay
from the PCM.
Whenever the ignition key is turned ON, the elec-
tric fuel pump will operate. But, the PCM will shut-
down the ground circuit to the fuel pump relay in
approximately 1±3 seconds unless the engine is oper-
ating or the starter motor is engaged.
REMOVAL
The fuel pump relay is located in the Power Distri-
bution Center (PDC) (Fig. 19). Refer to label on PDC
cover for relay location.
(1) Remove PDC cover.
(2) Remove relay from PDC.
(3) Check condition of relay terminals and PDC
connector terminals for damage or corrosion. Repair
if necessary before installing relay.
(4) Check for pin height (pin height should be the
same for all terminals within the PDC connector).
Repair if necessary before installing relay.
INSTALLATION
The fuel pump relay is located in the Power Distri-
bution Center (PDC). Refer to label on PDC cover for
relay location.
(1) Install relay to PDC.
(2) Install cover to PDC.
IDLE AIR CONTROL MOTOR
DESCRIPTION
A separate IAC motor is not used with the 5.7L V-8
engine.
The IAC stepper motor is mounted to the throttle
body, and regulates the amount of air bypassing the
control of the throttle plate. As engine loads and
ambient temperatures change, engine rpm changes.
A pintle on the IAC stepper motor protrudes into a
passage in the throttle body, controlling air flow
through the passage. The IAC is controlled by the
Powertrain Control Module (PCM) to maintain the
target engine idle speed.
OPERATION
A separate IAC motor is not used with the 5.7L V-8
engine.
At idle, engine speed can be increased by retract-
ing the IAC motor pintle and allowing more air to
pass through the port, or it can be decreased by
restricting the passage with the pintle and diminish-
ing the amount of air bypassing the throttle plate.
The IAC is called a stepper motor because it is
moved (rotated) in steps, or increments. Opening the
IAC opens an air passage around the throttle blade
which increases RPM.
The PCM uses the IAC motor to control idle speed
(along with timing) and to reach a desired MAP dur-
ing decel (keep engine from stalling).
Fig. 19 PDC LOCATION
1 - BATTERY
2 - PDC (POWER DISTRIBUTION CENTER)
DRFUEL INJECTION - GAS 14 - 33
FUEL INJECTOR (Continued)