
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - PERFORMANCE
PERFORMANCE DIAGNOSIS CHARTÐGASOLINE ENGINES
CONDITION POSSIBLE CAUSES CORRECTION
ENGINE WILL NOT CRANK 1. Weak or dead battery 1. Charge/Replace Battery. (Refer to
8 - ELECTRICAL/BATTERY
SYSTEM/BATTERY - STANDARD
PROCEDURE). Check charging
system. (Refer to 8 - ELECTRICAL/
CHARGING - DIAGNOSIS AND
TESTING).
2. Corroded or loose battery
connections2. Clean/tighten suspect battery/
starter connections
3. Faulty starter or related circuit(s) 3. Check starting system. (Refer to
8 - ELECTRICAL/STARTING -
DIAGNOSIS AND TESTING)
4. Seized accessory drive
component4. Remove accessory drive belt and
attempt to start engine. If engine
starts, repair/replace seized
component.
5. Engine internal mechanical
failure or hydro-static lock5. Refer to (Refer to 9 - ENGINE -
DIAGNOSIS AND TESTING)
ENGINE CRANKS BUT WILL NOT
START1. No spark 1. Check for spark. (Refer to 8 -
ELECTRICAL/IGNITION CONTROL
- DESCRIPTION)
2. No fuel 2. Perform fuel pressure test, and if
necessary, inspect fuel injector(s)
and driver circuits. (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY/
FUEL PUMP - DIAGNOSIS AND
TESTING).
3. Low or no engine compression 3. Perform cylinder compression
pressure test. (Refer to 9 - ENGINE
- DIAGNOSIS AND TESTING).
ENGINE LOSS OF POWER 1. Worn or burned distributor rotor 1. Install new distributor rotor
2. Worn distributor shaft 2. Remove and repair distributor
(Refer to 8 - ELECTRICAL/
IGNITION CONTROL/
DISTRIBUTOR - REMOVAL).
3. Worn or incorrect gapped spark
plugs3. Clean plugs and set gap. (Refer
to 8 - ELECTRICAL/IGNITION
CONTROL/SPARK PLUG -
CLEANING).
4. Dirt or water in fuel system 4. Clean system and replace fuel
filter
5. Faulty fuel pump 5. Install new fuel pump
6. Incorrect valve timing 6. Correct valve timing
BR/BEENGINE 8.0L 9 - 59
ENGINE 8.0L (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
4. Excessive connecting rod
bearing clearanceMeasure 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
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 pump suction tube loose,
broken, bent or clogged8. Inspect suction tube 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
9 - 62 ENGINE 8.0LBR/BE
ENGINE 8.0L (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
DIAGNOSIS AND TESTINGÐENGINE
DIAGNOSIS - LUBRICATION
CONDITION POSSIBLE CAUSES CORRECTION
OIL LEAKS 1. Gaskets and O-Rings. 1.
(a) Misaligned or damaged. (a) Replace as necessary.
(b) Loose fasteners, broken or
porous metal parts.(b) Tighten fasteners, Repair or
replace metal parts.
2. Crankshaft rear seal 2. Replace as necessary.
3. Crankshaft seal flange.
Scratched, nicked or grooved.3. Polish or replace crankshaft.
4. Oil pan flange cracked. 4. Replace oil pan.
5. Timing chain cover seal,
damaged or misaligned.5. Replace seal.
6. Scratched or damaged vibration
damper hub.6. Polish or replace damper.
OIL PRESSURE DROP 1. Low oil level. 1. Check and correct oil level.
2. Faulty oil pressure sending unit. 2. Replace sending unit.
3. Low oil pressure. 3. Check pump and bearing
clearance.
4. Clogged oil filter. 4. Replace oil filter.
5. Worn oil pump. 5. Replace as necessary.
6. Thin or diluted oil. 6. Change oil and filter.
7. Excessive bearing clearance. 7. Replace as necessary.
8. Oil pump relief valve stuck. 8. Clean or replace relief valve.
9. Oil pump suction tube loose or
damaged.9. Replace as necessary.
BR/BEENGINE 8.0L 9 - 63
ENGINE 8.0L (Continued)

(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) Remove the battery.
(2) Drain cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(3) Discharge the air conditioning system, if
equipped (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - STANDARD PROCEDURE).
(4) Remove the upper crossmember.
(5) Remove the transmission oil cooler (Refer to 7 -
COOLING/TRANSMISSION/TRANS COOLER -
REMOVAL).
(6) Remove the serpentine belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - REMOV-
AL).
(7) Remove the A/C compressor with the lines
attached (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/A/C COMPRESSOR -
REMOVAL). Set aside.
(8) If equipped, remove the condenser (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING/
A/C CONDENSER - REMOVAL).(9) Remove the washer fluid reservoir bottle (Refer
to 8 - ELECTRICAL/WIPERS/WASHERS -
REMOVAL AND INSTALLATION).
(10) Disconnect the top radiator hose.
(11) Remove the fan (Refer to 7 - COOLING/EN-
GINE/RADIATOR FAN - REMOVAL).
(12) Remove the fan shroud.
(13) Disconnect the lower radiator hose.
(14) Disconnect the transmission cooler lines.
(15) Remove radiator (Refer to 7 - COOLING/EN-
GINE/RADIATOR - REMOVAL).
(16) Remove the generator with the wire connec-
tions (Refer to 8 - ELECTRICAL/CHARGING/GEN-
ERATOR - REMOVAL).
(17) Remove the air cleaner.
(18) Disconnect the throttle linkage.
(19) Remove throttle body (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/THROTTLE BODY -
REMOVAL).
(20) Remove the upper intake manifold (Refer to 9
- ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL).
(21) Remove the coil assemblies with the ignition
cables.
(22) Disconnect the heater hoses.
(23) Disconnect the power steering hoses, if
equipped.
(24) Perform the Fuel System Pressure release
procedure (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY - STANDARD PROCEDURE). Disconnect
the fuel line (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/QUICK CONNECT FITTING - STAN-
DARD PROCEDURE).
(25) On Manual Transmission vehicles, remove the
shift lever.
(26) Raise and support the vehicle on a hoist.
(27) Remove the drain plug and drain the engine
oil.
(28) Loosen front engine mount thru-bolt nuts.
(29) Remove the transmission cooler line brackets
from oil pan.
(30) Disconnect exhaust pipe at manifold.
(31) Disconnect the starter wires. Remove starter
motor (Refer to 8 - ELECTRICAL/STARTING/
STARTER MOTOR - REMOVAL).
(32) Remove transmission.
(33) Lower vehicle.
CAUTION: DO NOT lift the engine by the intake
manifold.
(34) Install an engine lifting fixture.
(35) Remove engine from vehicle and install
engine assembly on a repair stand.
BR/BEENGINE 8.0L 9 - 67
ENGINE 8.0L (Continued)

INSTALLATION
(1) Remove engine from the repair stand and posi-
tion in the engine compartment. Position the thru-
bolt into the support cushion brackets.
(2) Install an engine support fixture.
(3) Raise and support the vehicle on a hoist.
(4) Install Transmission.
(5) Install the starter and connect the starter
wires (Refer to 8 - ELECTRICAL/STARTING/
STARTER MOTOR - INSTALLATION).
(6) Install exhaust pipe to manifold.
(7) Install the transmission cooler line brackets
from oil pan.
(8) Tighten the Front mount thru-bolts and nuts to
102N´m (75 ft. lbs.).
(9) Install the drain plug and tighten to 34 N´m
(25 ft. lbs.) torque.
(10) Prime oil pump by squirting oil in the oil fil-
ter mounting hole and filling the J-trap of the front
timing cover. When oil is running out, install oil filter
that has been filled with oil.
(11) Lower the vehicle.
(12) Remove engine lifting fixture.
(13) On Manual Transmission vehicles, install the
shift lever.
(14) Connect the fuel lines (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/QUICK CONNECT FIT-
TING - STANDARD PROCEDURE).
(15) Connect the heater hoses.
(16) Install the upper intake manifold (Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(17) Install the coil assemblies with the ignition
cables.
(18) Using a new gasket, install throttle body
(Refer to 14 - FUEL SYSTEM/FUEL INJECTION/
THROTTLE BODY - INSTALLATION).
(19) Connect the throttle linkage.
(20) Install the air cleaner box.
(21) Install the generator and wire connections
(Refer to 8 - ELECTRICAL/CHARGING/GENERA-
TOR - INSTALLATION).
(22) Install the upper crossmember.
(23) Install radiator (Refer to 7 - COOLING/EN-
GINE/RADIATOR - INSTALLATION).
(24) Connect the lower radiator hose.
(25) Install the transmission oil cooler (Refer to 7 -
COOLING/TRANSMISSION/TRANS COOLER -
INSTALLATION).
(26) Connect the transmission cooler lines.
(27) Connect the power steering hoses, if equipped.
(28) Install the fan shroud.
(29) Install the fan (Refer to 7 - COOLING/EN-
GINE/RADIATOR FAN - INSTALLATION).
(30) Connect the top radiator hose.(31) Install the washer fluid reservoir bottle (Refer
to 8 - ELECTRICAL/WIPERS/WASHERS - INSTAL-
LATION).
(32) If equipped, install the condenser (Refer to 24
- HEATING & AIR CONDITIONING/PLUMBING/
A/C CONDENSER - INSTALLATION).
(33) Install the A/C compressor with the lines
attached (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING/A/C COMPRESSOR -
INSTALLATION).
(34) Install the serpentine belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).
(35) Evacuate (Refer to 24 - HEATING & AIR
CONDITIONING/PLUMBING - STANDARD PRO-
CEDURE) and charge the air conditioning system, if
equipped (Refer to 24 - HEATING & AIR CONDI-
TIONING/PLUMBING - STANDARD PROCEDURE).
(36) Add coolant to the cooling system (Refer to 7 -
COOLING - STANDARD PROCEDURE).
(37) Install the battery.
(38) Warm engine and adjust as required.
(39) Road test vehicle.
SPECIFICATIONS
8.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
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
9 - 68 ENGINE 8.0LBR/BE
ENGINE 8.0L (Continued)

AIR CLEANER ELEMENT
REMOVAL - 8.0L
For air cleaner element required maintenance
schedules (listed in time or mileage intervals), refer
to 0, Lubrication and Maintenance.
A small amount of engine oil wetting the inside of
the air cleaner housing is normal. When servicing,
wipe out oil from air cleaner housing.
(1) Loosen clamp (Fig. 4) and remove air inlet tube
(Fig. 5) at front of air cleaner housing cover.
(2) The air cleaner housing and air cleaner ele-
ment cover are equipped with spring clips to seal
cover to housing (Fig. 5). Unlatch clips from air
cleaner cover and remove cover from air cleaner
housing.
(3) Remove air cleaner element from air cleaner
cover.
(4) Before installing a new air cleaner element,
clean inside of air cleaner housing.
(5) If housing removal is necessary, disconnect
crankcase vent hose and remove 4 housing-to-throttle
body nuts.
INSTALLATION - 8.0L
For air cleaner element required maintenance
schedules (listed in time or mileage intervals), refer
to Group 0, Lubrication and Maintenance.
(1) After installing housing, tighten 4 nuts to 11
N´m (96 in. lbs.) torque and connect crankcase vent
hose.
(2) Position air cleaner element (filter) into air
cleaner cover. Latch spring clips to seal cover to
housing.(3) Install air inlet tube at air cleaner housing
inlet.
(4) Install and tighten clamp at air inlet tube (Fig.
6).
Fig. 4 Clamp RemovalÐ8.0L Engine
1 - CLAMP
2 - ADJUSTABLE PLIERS
3 - REMOVAL
Fig. 5 Air Cleaner HousingÐ8.0L V-10 Engine
1 - HOUSING
2 - HOUSING COVER
3 - AIR INLET TUBE
4 - CLAMP
5 - SPRING CLIPS
Fig. 6 Clamp InstallationÐ8.0L Engine
1 - CLAMP
2 - ADJUSTABLE PLIERS
BR/BEENGINE 8.0L 9 - 75

(5) If the oil leak source is not positively identified
at this time, proceed with the air leak detection test
method as follows:
(6) Disconnect the breather cap to air cleaner hose
at the breather cap end. Cap or plug breather cap
nipple.
(7) Remove the PCV valve from the cylinder head
cover. Cap or plug the PCV valve grommet.
(8) Attach an air hose with pressure gauge and
regulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
(9) Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provide the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
(10) If the leakage occurs at the rear oil seal area,
refer to the section, Inspection for Rear Seal Area
Leak.
(11) If no leaks are detected, turn off the air sup-
ply and remove the air hose and all plugs and caps.
Install the PCV valve and breather cap hose. Proceed
to next step.
(12) Clean the oil off the suspect oil leak area
using a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
DIAGNOSIS AND TESTINGÐENGINE OIL
PRESSURE
(1) Remove oil pressure sending unit.
(2) Install Oil Pressure Line and Gauge Tool
C-3292. Start engine and record pressure. (Refer to 9
- ENGINE - SPECIFICATIONS).
OIL
STANDARD PROCEDURE - ENGINE OIL
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the right
front of the engine, left of the generator (Fig. 53).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
1 - OIL TO MAIN OIL GALLERIES
2 - RELIEF VALVE
3 - OIL GALLERY FOR TAPPETS
4 - MAIN OIL GALLERY
5 - TAPPET OIL GALLERY
6 - HOLLOW PUSH ROD
7 - ROCKER ARM
8 - PLUG
9 - GASKET
10 - SPRING
11 - TIMING CHAIN COVER
12 - CAM BEARINGS
13 - HYDRAULIC TAPPET GALLERIES
14 - CAMSHAFT
15 - CRANKSHAFT
16 - OIL PASSAGE TO CONNECTING ROD JOURNALS17 - OIL PICKUP
18 - CONNECTING ROD JOURNALS
19 - CRANKSHAFT BEARINGS
20 - MAIN OIL GALLERY
21 - CRANKSHAFT
22 - OIL PICKUP TUBE
23 - CONNECT ROD JOURNALS
24 - CAMSHAFT BEARINGS
25 - TAPPET OIL GALLERY
26 - OIL FROM PICKUP TUBE
27 - CAMSHAFT
28 - TAPPET
29 - VALVE
30 - OIL PUMP RELIEF VALVE
Fig. 53 Oil Level Indicator Location
1 - CYLINDER HEAD COVER
2 - ENGINE OIL FILL CAP
3 - DIPSTICK
4 - ENGINE OIL FILTER
5 - FILTER BOSS
BR/BEENGINE 8.0L 9 - 101
LUBRICATION (Continued)

(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. 56)
. 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.
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. 57)
.
(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. 56) .After the sealant is appliedyou 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. 58) . 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.
Fig. 56 Oil Pick-Up Tube
1 - PICKÐUP TUBE
2 - SEALANT AT SPLIT-LINES
3 - SEALANT AT SPLIT-LINE
Fig. 57 Fabrication of Alignment Dowels
1 - 5/16º X 1óº BOLT
2 - DOWEL
3 - SLOT
Fig. 58 Oil Pan Bolt Location
1 - OIL PAN
2 - OIL FILTER
3 - STUD BOLTS
4 - DRAIN PLUG
BR/BEENGINE 8.0L 9 - 103
OIL PAN (Continued)