Transmission DODGE RAM 2003 Service Repair Manual

DESCRIPTION N´m Ft. In.
Heat ShieldÐNuts 20 Ð 175
Hydraulic Tappet Yoke
Retaining22 16 Ð
SpiderÐBolts
Intake Manifold (Lower)Ð
Bolts54 40 Ð
Intake Manifold (Upper)Ð
Bolts22 16 Ð
Oil Filter 9 Ð 80 +
45É
Oil Filter Connector 46 34 Ð
Oil Pan
Ð1/4 - 20 Bolts 11 Ð 96
Ð5/16 - 18 Bolts 16 Ð 144
ÐStud Bolts 16 Ð 144
ÐDrain Plug 34 25 Ð
Oil Pan Pick Up TubeÐBolts 16 Ð 144
Oil Pump AttachingÐBolts 41 30 Ð
Oil Pump CoverÐBolts 14 Ð 125
Oil Pump Pressure
ReliefÐPlug20 15 Ð
Rocker ArmÐBolts 54 40 Ð
Spark Plugs 41 30 Ð
Starter MountingÐBolts 68 50 Ð
Timing Chain CoverÐBolts 47 35 Ð
Thermostat HousingÐBolts 25 Ð 220
Throttle BodyÐNuts 11 Ð 96
Transfer Case to Insulator
Mounting204 150 Ð
PlateÐNuts
Transmission Support
BracketÐ102 75 Ð
Bolts
Transmission Support
CushionÐ47 35 Ð
Bolts
Transmission Support
Cushion47 35 Ð
StudÐNuts
Water Pump to Chain Case
CoverÐ41 30 Ð
Bolts8.OL ENGINE
DESCRIPTION SPECIFICATION
CAMSHAFT
Bearing Diameter
No. 1 53.16 ± 53.19 mm
(2.093 ± 2.094 in.)
No. 2 52.76 ± 52.78 mm
(2.077 ± 2.078 in.)
No. 3 52.35 ± 52.37 mm
(2.061 ± 2.062 in.)
No. 4 51.94 ± 51.97 mm
(2.045 ± 2.046 in.)
No. 5 51.54 ± 51.56 mm
(2.029 ± 2.030 in.)
No. 6 48.74 ± 48.77 mm
(1.919 ± 1.920 in.)
Bearing Journal Diameter
No. 1 53.11 ± 53.14 mm
(2.091 ± 2.092 in.)
No. 2 52.69 ± 52.72 mm
(2.0745 ± 2.0755 in.)
No. 3 52.30 ± 52.32 mm
(2.059 ± 2.060 in.)
No. 4 51.89 ± 51.92 mm
(2.043 ± 2.044 in.)
No. 5 51.49 ± 51.51 mm
(2.027 ± 2.028 in.)
No. 6 48.69 ± 48.72 mm
(1.917 ± 1.918 in.)
Bearing to Journal
Clearance
No. 1,3,4,5,6 0.0254 ± 0.0762 mm
(0.001 ± 0.003 in.)
No. 2 0.0381 ± 0.0889 mm
(0.0005 ± 0.0035 in.)
Service Limit 0.127 mm (0.005 in.)
End Play 0.127 ± 0.381 mm
(0.005 ± 0.015 in.)
9 - 364 ENGINE 8.0LDR
ENGINE 8.0L (Continued)

fuel line (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY/QUICK CONNECT FITTING - STANDARD
PROCEDURE).
(9) Disconnect accelerator linkage and if so
equipped, the speed control and transmission kick-
down cables.
(10) Remove coil pack and bracket (Fig. 8).
(11) Disconnect the coil wires.
(12) Disconnect heat indicator sending unit wire.
(13) Disconnect heater hoses and bypass hose.
(14) Remove upper intake manifold and throttle
body as an assembly (Refer to 9 - ENGINE/MANI-
FOLDS/INTAKE MANIFOLD - REMOVAL).
(15) Remove cylinder head covers and gaskets
(Refer to 9 - ENGINE/CYLINDER HEAD/CYLIN-
DER HEAD COVER(S) - REMOVAL).
(16) Remove the EGR tube. Discard the gasket, for
right side only.
(17) Remove lower intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL). Discard the flange side gaskets and the
front and rear cross-over gaskets.
(18) Disconnect exhaust pipe from exhaust mani-
fold.
(19) Remove exhaust manifolds and gaskets (Refer
to 9 - ENGINE/MANIFOLDS/EXHAUST MANIFOLD
- REMOVAL).
(20) Remove rocker arm assemblies and push rods
(Refer to 9 - ENGINE/CYLINDER HEAD/ROCKER
ARM / ADJUSTER ASSY - REMOVAL). Identify to
ensure installation in original locations.(21) Remove the head bolts from each cylinder
head and remove cylinder heads. Discard the cylin-
der head gasket.
(22) Remove spark plugs.
CLEANING
Clean all surfaces of cylinder block and cylinder
heads. Be sure material does not fall into the lifters
and surrounding valley.
Clean cylinder block front and rear gasket surfaces
using a suitable solvent.
Clean the exhaust manifold to cylinder head mat-
ing areas.
INSPECTION
Inspect all surfaces with a straightedge if there is
any reason to suspect leakage. The out-of-flatness
specifications are 0.0007 mm/mm (0.0004 inch/inch),
0.127 mm/152 mm (0.005 inch/6 inches) any direction
or 0.254 mm (0.010 inch) overall across head. If
exceeded, either replace head or lightly machine the
head surface.
The cylinder head surface finish should be
1.78-4.57 microns (15-80 microinches).
Inspect push rods. Replace worn or bent rods.
Inspect rocker arms. Replace if worn or scored.
INSTALLATION
(1) Position the new cylinder head gaskets onto
the cylinder block.
(2) Position the cylinder heads onto head gaskets
and cylinder block.
(3) Tighten the cylinder head bolts in two steps
(Fig. 9):
²Step 1ÐTighten all cylinder head bolts, in
sequence, to 58 N´m (43 ft. lbs.) torque.
²Step 2ÐTighten all cylinder head bolts, in
sequence, to 143 N´m (105 ft. lbs.) torque.
²
CAUTION: When tightening the rocker arm bolts,
make sure the piston in that cylinder is NOT at
TDC. Contact between the valves and piston could
occur.
Fig. 8 Coil Pack and Bracket
1 - COIL PACKS AND BRACKET
2 - MOUNTING BOLTS (4)
Fig. 9 Cylinder Head Bolt Tightening Sequence
9 - 372 ENGINE 8.0LDR
CYLINDER HEAD (Continued)

(4) Install push rods and rocker arm assemblies in
their original position (Refer to 9 - ENGINE/CYLIN-
DER HEAD/ROCKER ARM / ADJUSTER ASSY -
INSTALLATION).
(5) Install lower intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(6) Install the upper intake manifold onto the
lower intake manifold (Refer to 9 - ENGINE/MANI-
FOLDS/INTAKE MANIFOLD - INSTALLATION).
(7) Install the exhaust manifolds and new gaskets
(Refer to 9 - ENGINE/MANIFOLDS/EXHAUST
MANIFOLD - INSTALLATION).
(8) Install exhaust pipe to the exhaust manifold.
Tighten the bolts to 34 n´m (25 ft. lbs.) torque.
(9) Using a new gasket, position the EGR tube to
the intake manifold and the exhaust manifold.
Tighten the EGR tube nut to 34 N´m (25 ft. lbs.)
torque. Tighten the bolts to 20 N´m (174 in. lbs.)
torque.
(10) Install the heat shields and the washers.
Make sure that heat shields tabs hook over the
exhaust gasket.Tighten the nuts to 15 N´m (132 in.
lbs.) torque.
(11) Adjust and Install the spark plugs (Refer to 8
- ELECTRICAL/IGNITION CONTROL/SPARK
PLUG - INSTALLATION).
(12) Install coil packs and bracket. Tighten the
bracket bolts to 21 N´m (190 in. lbs.) torque. Connect
the coil wires.
(13) Connect heat indicator sending unit wire.
(14) Connect the heater hoses and bypass hose.
(15) Connect the accelerator linkage and if so
equipped, the speed control and transmission kick-
down cables.
(16) Install the fuel line (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE).
(17) Install the generator (Refer to 8 - ELECTRI-
CAL/CHARGING/GENERATOR - INSTALLATION)
and drive belt (Refer to 7 - COOLING/ACCESSORY
DRIVE/DRIVE BELTS - INSTALLATION).
(18) Install the intake manifold-to-generator
bracket support rod. Tighten the bolts to 41 N´m (30
ft. lbs.) torque.
(19) 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.(20) Install cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(21) Install closed crankcase ventilation system.
(22) Connect the evaporation control system.
(23) Install the air cleaner.
(24) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(25) Connect the negative cable to the battery.
(26) Check for leaks (fuel, oil, antifreeze, etc.).
CYLINDER HEAD COVER(S)
DESCRIPTION
Die-cast magnesium cylinder head covers (Fig. 10)
reduce noise and provide a good sealing surface. A
steel backed silicon gasket is used with the cylinder
head cover. This gasket can be used again.
REMOVAL
Die-cast magnesium cylinder head covers (Fig. 12)
reduce noise and provide a good sealing surface. A
steel backed silicon gasket is used with the cylinder
head cover (Fig. 11).
(1) Disconnect the negative cable from the battery.
(2) Disconnect closed ventilation system and evap-
oration control system from cylinder head cover.
Identify each system for installation.
(3) Remove the upper intake manifold to remove
the right side head cover (Refer to 9 - ENGINE/
MANIFOLDS/INTAKE MANIFOLD - REMOVAL).
Fig. 10 Cylinder Head Cover
1 - CYLINDER HEAD COVER
DRENGINE 8.0L 9 - 373
CYLINDER HEAD (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)

(2) Use tool 6761 to support timing chain cover
when installing oil seal with tool 6806 (Fig. 33),
install seal (Fig. 34).(3) Install engine front cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
CRANKSHAFT OIL SEAL -
REAR
REMOVAL
NOTE: This procedure does not require the removal
of the seal retainer from the engine block.
(1) Remove the transmission.
(2) Carefully, remove the rear seal from the
retainer. Discard the oil seal.
INSTALLATION
(1) Wash all parts in a suitable solvent and inspect
carefully for damage or wear.
(2) Position Special Tool 6687 Seal Guide, onto the
crankshaft.
(3) Position the oil seal onto the Seal guide, then
using Special Tool 8359 Seal Installer and C±4171
Driver Handle, Install the oil seal.
(4) The seal face surface must be countersunk into
the retainer .762±1.27mm (0.030±0.050 in.).
(5) Install the transmission.
(6) Check and verify engine oil is at correct level.
(7) Start engine and check for leaks.
Fig. 32 Timing Chain Cover and Oil Seal
1 - SPECIAL TOOL C-3688
2 - SPECIAL TOOL 6806
Fig. 33 Oil Seal, ToolsÐ6806 and 6761
1 - FRONT COVER
2 - SPECIAL TOOL 6761
3 - FRONT OIL SEAL
4 - SPECIAL TOOL 6806
Fig. 34 Oil Seal Installed
1 - SPECIAL TOOL 6806
2 - SPECIAL TOOL 6761
DRENGINE 8.0L 9 - 385
CRANKSHAFT OIL SEAL - FRONT (Continued)

CRANKSHAFT REAR OIL SEAL
RETAINER
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove the transmission.
(3) Remove the drive plate / flywheel.
(4) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(5) Remove the rear oil seal retainer mounting
bolts.
(6) Carefully remove the retainer from the engine
block.
INSTALLATION
(1) Throughly clean all gasket resdue from the
engine block.
(2) Use extream care and clean all gasket resdue
from the retainer.
(3) Apply a small amount of MopartSilicone Rub-
ber Adhesive Sealant to the retainer gasket. Position
the gasket onto the retainer.
(4) Position Special Tool 6687 Seal Guide onto the
crankshaft.
(5) Position the retainer and seal over the guide
and onto the engine block.
(6) Install the retainer mounting bolts. Tighten the
bolts to 22 N´m (16 ft. lbs.).
(7) Install the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - INSTALLATION).
(8) Install the drive plate / flywheel.
(9) Install the transmission.
(10) Check and verify engine oil level.
(11) Start engine and check for leaks.
HYDRAULIC LIFTERS
DIAGNOSIS AND TESTINGÐHYDRAULIC
TAPPETS
Before disassembling any part of the engine to cor-
rect tappet noise, check the oil pressure. If vehicle
has no oil pressure gauge, install a reliable gauge at
the pressure sending-unit. The pressure should be
between 207-552 kPa (30-80 psi) at 3,000 RPM.
Check the oil level after the engine reaches normal
operating temperature. Allow 5 minutes to stabilize
oil level, check dipstick. The oil level in the pan
should never be above the FULL mark or below the
ADD OIL mark on dipstick. Either of these two con-
ditions could be responsible for noisy tappets.
OIL LEVEL
HIGH
If oil level is above the FULL mark, it is possible
for the connecting rods to dip into the oil. With the
engine running, this condition could create foam in
the oil pan. Foam in oil pan would be fed to the
hydraulic tappets by the oil pump causing them to
lose length and allow valves to seat noisily.
LOW
Low oil level may allow oil pump to take in air.
When air is fed to the tappets, they lose length,
which allows valves to seat noisily. Any leaks on
intake side of oil pump through which air can be
drawn will create the same tappet action. Check the
lubrication system from the intake strainer to the
pump cover, including the relief valve retainer cap.
When tappet noise is due to aeration, it may be
intermittent or constant, and usually more than one
tappet will be noisy. When oil level and leaks have
been corrected, operate the engine at fast idle. Run
engine for a sufficient time to allow all of the air
inside the tappets to be bled out.
TAPPET NOISE DIAGNOSIS
(1) To determine source of tappet noise, operate
engine at idle with cylinder head covers removed.
(2) Feel each valve spring or rocker arm to detect
noisy tappet. The noisy tappet will cause the affected
spring and/or rocker arm to vibrate or feel rough in
operation.
NOTE: Worn valve guides or cocked springs are
sometimes mistaken for noisy tappets. If such is
the case, noise may be dampened by applying side
thrust on the valve spring. If noise is not apprecia-
bly reduced, it can be assumed the noise is in the
tappet. Inspect the rocker arm push rod sockets
and push rod ends for wear.
(3) Valve tappet noise ranges from light noise to a
heavy click. A light noise is usually caused by exces-
sive leak-down around the unit plunger, or by the
plunger partially sticking in the tappet body cylinder.
The tappet should be replaced. A heavy click is
caused by a tappet check valve not seating, or by for-
eign particles wedged between the plunger and the
tappet body. This will cause the plunger to stick in
the down position. This heavy click will be accompa-
nied by excessive clearance between the valve stem
and rocker arm as valve closes. In either case, tappet
assembly should be removed for inspection and clean-
ing.
9 - 386 ENGINE 8.0LDR

(3) Lower engine with support/lifting fixture while
guiding the engine bracket/cushion and thru-bolt into
support cushion brackets.
(4) Install thru-bolt nuts and tighten the nuts to
68 N´m (50 ft. lbs.) torque.
(5) Lower the vehicle.
(6) Remove lifting fixture.
REAR MOUNT
REMOVAL
(1) Raise the vehicle on a hoist.
(2) Position a transmission jack in place.
(3) Remove support cushion stud nuts (Fig. 47).
(4) Raise rear of transmission and engine
SLIGHTLY.
(5) Remove the bolts holding the support cushion
to the transmission support bracket. Remove the sup-
port cushion.
(6) If necessary, remove the bolts holding the
transmission support bracket to the transmission.
INSTALLATION
(1) If removed, position the transmission support
bracket to the transmission. Install new attaching
bolts and tighten to 102 N´m (75 ft. lbs.) torque.(2) Position support cushion to transmission sup-
port bracket. Install stud nuts and tighten to 47 N´m
(35 ft. lbs.) torque.
(3) Using the transmission jack, lower the trans-
mission and support cushion onto the crossmember
(Fig. 110).
(4) Install the support cushion bolts and tighten to
47 N´m (35 ft. lbs.) torque.
(5) Remove the transmission jack.
(6) Lower the vehicle.
LUBRICATION
DESCRIPTION
A pressure feed type (gerotor) oil pump is located
in the engine front cover. The pump uses a pick-up
tube and screen assembly to gather engine oil from
the oil pan (Fig. 48).
OPERATION
The pump draws oil through the screen and inlet
tube from the sump at the rear of the oil pan. The oil
is driven between the inner and outer gears of the oil
pump, then forced through the outlet in the engine
front cover. An oil gallery in the front cover channels
the oil to the inlet side of the full flow oil filter. After
passing through the filter element, the oil passes
Fig. 47 Engine Rear Support Cushion Asse
DRENGINE 8.0L 9 - 393
FRONT MOUNT (Continued)

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 (Fig. 51).
(4) When filter separates from adapter nipple, tip
gasket end upward to minimize oil spill. Remove fil-
ter from vehicle.
(5) With a wiping cloth, clean the gasket sealing
surface (Fig. 52) of oil and grime.
(6) Install new filter (Refer to 9 - ENGINE/LUBRI-
CATION/OIL FILTER - INSTALLATION).
INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil or chassis grease.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 52) hand
tighten filter one full turn, do not over tighten.
(3) Add oil (Refer to 9 - ENGINE/LUBRICATION/
OIL - STANDARD PROCEDURE).
OIL PAN
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Raise vehicle.
(3) Drain engine oil.
(4) Remove left engine to transmission strut.
(5) Remove oil pan mounting bolts, pan and one-
piece gasket. The engine may have to be raised
slightly on 2WD vehicles.(6) Remove the oil pick-up tube assembly (Fig. 53).
Discard the gasket.
CLEANING
Clean the block and pan gasket surfaces.
If present, trim excess sealant from inside the
engine.
Clean oil pan in solvent and wipe dry with a clean
cloth.
Clean oil screen and pipe thoroughly in clean sol-
vent. Inspect condition of screen.
INSPECTION
Inspect oil drain plug and plug hole for stripped or
damaged threads. Repair as necessary.
Inspect oil pan mounting flange for bends or distor-
tion. Straighten flange, if necessary.
Fig. 51 Oil Filter RemovalÐTypical
1 - ENGINE OIL FILTER
2 - OIL FILTER WRENCH
Fig. 52 Oil Filter Sealing SurfaceÐTypical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTER
Fig. 53 Oil Pick-Up Tube
1 - PICKÐUP TUBE
2 - SEALANT AT SPLIT-LINES
3 - SEALANT AT SPLIT-LINE
DRENGINE 8.0L 9 - 397

INSTALLATION
(1) Fabricate 4 alignment dowels from 5/16x11/2
inch bolts. Cut the head off the bolts and cut a slot
into the top of the dowel. This will allow easier
installation and removal with a screwdriver (Fig. 54).
(2) Install the dowels in the cylinder block at the
four corners.
(3) Apply small amount of MopartSilicone Rubber
Adhesive Sealant, or equivalent at the split lines.
The split lines are between the cylinder block, the
timing chain cover and the rear crankshaft seal
assembly (Fig. 53).After the sealant is applied
you have 3 minutes to install the gasket and oil
pan.
(4) Slide the one-piece gasket over the dowels and
onto the block.
(5) Position the oil pan over the dowels and onto
the gasket. The engine may have to be slightly raised
on 2WD vehicles.
(6) Install the oil pan bolts (Fig. 55). Tighten the
bolts to as shown in Oil Pan Bolts Torque Chart.(7) Remove the dowels. Install the remaining 5/16
inch oil pan bolts. Torque these bolts as shown in Oil
Pan Bolts Torque Chart.
(8) Install the drain plug. Tighten drain plug to 34
N´m (25 ft. lbs.) torque.
(9) Install the engine to transmission strut.
(10) Lower vehicle.
(11) Connect the negative cable to the battery.
(12) Fill crankcase with oil to proper level.
(13) Start engine and check for leaks.
OIL PUMP
REMOVAL
(1) Remove the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(2) Remove the relief valve plug, gasket, spring
and valve (Fig. 56). Discard the gasket.
(3) Remove mounting screws and oil pump cover
(Fig. 57).
(4) Remove oil pump inner and outer rotors (Fig.
57).
(5) Inspect oil pump for wear (Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP - INSPEC-
TION).
CLEANING
Wash all parts in a suitable solvent and inspect
carefully for damage or wear.
Fig. 54 Fabrication of Alignment Dowels
1 - 5/16º X 11¤2º BOLT
2 - DOWEL
3 - SLOT
Fig. 55 Oil Pan Bolt Location
1 - OIL PAN
2 - OIL FILTER
3 - STUD BOLTS
4 - DRAIN PLUG
Fig. 56 Oil Pressure Relief Valve
1 - TIMING CHAIN COVER
2 - OIL PUMP RELIEF VALVE
3 - SPRING
4 - GASKET
5 - PLUG
9 - 398 ENGINE 8.0LDR
OIL PAN (Continued)

(7) Using a new pressure relief valve gasket,
install the relief valve plug. Tighten the plug to 20
N´m (15 ft. lbs.) torque.
(8) Install oil filter that has been filled with oil.
INTAKE MANIFOLD
DESCRIPTION
The aluminum intake manifold (Fig. 65) has two
plenum chambers an upper and lower which supply
air to five runners each. Passages across the longitu-
dinal center of the manifold feed air from the throttle
body to the plenum chambers.
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 RPMs occur, the area of the sus-
pected leak has been found.
(4) Repair as required.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Drain the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(3) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(4) Remove the generator brace and generator
(Fig. 66).
(5) Remove the A/C compressor brace (Fig. 66).
Remove the compressor and set aside.
(6) Remove the air cleaner cover and filter.
Remove the air cleaner housing (Fig. 67). Discard the
gasket.
(7) Perform the Fuel System Pressure release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE). Disconnect the
fuel lines (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/QUICK CONNECT FITTING - STAN-
DARD PROCEDURE).
(8) Disconnect the accelerator linkage and if so
equipped, the speed control and transmission kick-
down cables.
(9) Remove the coil assemblies with the ignition
wires.
(10) Disconnect the vacuum lines.
(11) Disconnect the heater hoses and bypass hose.
(12) Remove the closed crankcase ventilation and
evaporation control systems.
Fig. 65 Upper and Lower Intake ManifoldÐ8.0L
Engine
1 - UPPER INTAKE MANIFOLD
2 - THROTTLE BODY (MPI)
3 - LOWER INTAKE MANIFOLD
Fig. 66 Generator and A/C Compressor Braces
1 - GENERATOR
2 - INTAKE MANIFOLD TO GENERATOR BRACE
3 - A/C COMPRESSOR
4 - INTAKE MANIFOLD TO A/C COMPRESSOR BRACE
DRENGINE 8.0L 9 - 401
OIL PUMP (Continued)