2002 DODGE RAM oil pressure

CONDITION POSSIBLE CAUSES CORRECTION
3. Dirt in fuel system 3. Clean fuel system
4. Burned, warped or pitted valves 4. Install new valves
5. Faulty coil 5. Test and replace as necessary
(Refer to 8 - ELECTRICAL/
IGNITION CONTROL/IGNITION
COIL - REMOVAL)
DIAGNOSIS AND TESTINGÐ ENGINE
DIAGNOSIS - MECHANICAL
ENGINE MECHANICAL DIAGNOSIS CHART
CONDITION POSSIBLE CAUSES CORRECTION
NOISY VALVES/LIFTERS 1. High or low oil level in crankcase 1. Check for correct oil level. Adjust
oil level by draining or adding as
needed
2. Thin or diluted oil 2. Change oil. (Refer to 9 -
ENGINE/LUBRICATION/OIL -
STANDARD PROCEDURE)
3. Low oil pressure 3. Check engine oil level. If ok,
Perform oil pressure test. (Refer to
9 - ENGINE/LUBRICATION -
DIAGNOSIS AND TESTING) for
engine oil pressure test/
specifications
4. Dirt in tappets/lash adjusters 4. Clean/replace hydraulic
tappets/lash adjusters
5. Bent push rod(s) 5. Install new push rods
6. Worn rocker arms 6. Inspect oil supply to rocker arms
and replace worn arms as needed
7. Worn tappets/lash adjusters 7. Install new hydraulic tappets/lash
adjusters
8. Worn valve guides 8. Inspect all valve guides and
replace as necessary
9. Excessive runout of valve seats
or valve faces9. Grind valves and seats
CONNECTING ROD 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) engine
oil pressure test/specifications
3. Thin or diluted oil 3. Change oil to correct viscosity.
(Refer to 9 - ENGINE/
LUBRICATION/OIL - STANDARD
PROCEDURE) for correct
procedure/engine oil specifications
BR/BEENGINE 8.0L 9 - 61
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)

CONDITION POSSIBLE CAUSES CORRECTION
OIL PUMPING AT RINGS; SPARK
PLUGS FOULING1. Worn or damaged rings. 1. Hone cylinder bores and replace
rings.
2. Carbon in oil ring slots. 2. Replace rings.
3. Incorrect ring size installed. 3. Replace rings.
4. Worn valve guides. 4. Ream guides and replace valves.
5. Leaking intake gasket. 5. Replace intake gaskets.
6. Leaking valve guide seals. 6. Replace valve guide seals.
DIAGNOSIS AND TESTINGÐCYLINDER
COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise, the indicated compression pressures may
not be valid for diagnosis purposes.
(1) Clean the spark plug recesses with compressed
air.
(2) Remove the spark plugs (Refer to 8 - ELEC-
TRICAL/IGNITION CONTROL/SPARK PLUG -
REMOVAL).
(3) Secure the throttle in the wide-open position.
(4) Disconnect the ignition coil.
(5) Insert a compression pressure gauge and rotate
the engine with the engine starter motor for three
revolutions.
(6) Record the compression pressure on the third
revolution. Continue the test for the remaining cylin-
ders.
(Refer to 9 - ENGINE - SPECIFICATIONS) for the
correct engine compression pressures.
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:
²Exhaust and intake valve leaks (improper seat-
ing)
²Leaks between adjacent cylinders or into water
jacket²Any causes for combustion/compression pressure
loss
WARNING: DO NOT REMOVE THE RADIATOR CAP
WITH THE SYSTEM HOT AND UNDER PRESSURE.
SERIOUS BURNS FROM HOT COOLANT CAN
OCCUR.
Check the coolant level and fill as required. DO
NOT install the radiator cap.
Start and operate the engine until it attains nor-
mal operating temperature, then turn OFF the
engine.
Remove the spark plugs.
Remove the oil filler cap.
Remove the air cleaner.
Calibrate the tester according to the manufactur-
er's instructions. The shop air source for testing
should maintain 483 kPa (70 psi) minimum, 1,379
kPa (200 psi) maximum and 552 kPa (80 psi) recom-
mended.
Perform the test procedure on each cylinder accord-
ing to the tester manufacturer's instructions. While
testing, listen for pressurized air escaping through
the throttle body, tailpipe or oil filler cap opening.
Check for bubbles in the radiator coolant.
All gauge pressure indications should be equal,
with no more than 25% leakage.
FOR EXAMPLE:At 552 kPa (80 psi) input pres-
sure, a minimum of 414 kPa (60 psi) should be main-
tained in the cylinder CYLINDER COMBUSTION
PRESSURE LEAKAGE DIAGNOSIS CHART.
9 - 64 ENGINE 8.0LBR/BE
ENGINE 8.0L (Continued)

CYLINDER COMBUSTION PRESSURE LEAKAGE DIAGNOSIS CHART
CONDITION POSSIBLE CAUSE CORRECTION
AIR ESCAPES THROUGH
THROTTLE BODYIntake valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary
AIR ESCAPES THROUGH
TAILPIPEExhaust valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary
AIR ESCAPES THROUGH
RADIATORHead gasket leaking or cracked
cylinder head or blockRemove cylinder head and inspect.
Replace defective part
MORE THAN 50% LEAKAGE
FROM ADJACENT CYLINDERSHead gasket leaking or crack in
cylinder head or block between
adjacent cylindersRemove cylinder head and inspect.
Replace gasket, head, or block as
necessary
MORE THAN 25% LEAKAGE AND
AIR ESCAPES THROUGH OIL
FILLER CAP OPENING ONLYStuck or broken piston rings;
cracked piston; worn rings and/or
cylinder wallInspect for broken rings or piston.
Measure ring gap and cylinder
diameter, taper and out-of-round.
Replace defective part as necessary
STANDARD PROCEDURE
STANDARD PROCEDUREÐCYLINDER BORE
HONING
Before honing, stuff plenty of clean shop towels
under the bores and over the crankshaft to keep
abrasive materials from entering the crankshaft
area.
(1) Used carefully, the Cylinder Bore Sizing Hone
C-823, equipped with 220 grit stones, is the best tool
for this job. In addition to deglazing, it will reduce
taper and out-of-round, as well as removing light
scuffing, scoring and scratches. Usually, a few strokes
will clean up a bore and maintain the required lim-
its.
CAUTION: DO NOT use rigid type hones to remove
cylinder wall glaze.
(2) Deglazing of the cylinder walls may be done if
the cylinder bore is straight and round. Use a cylin-
der surfacing hone, Honing Tool C-3501, equipped
with 280 grit stones (C-3501-3810). about 20-60
strokes, depending on the bore condition, will be suf-
ficient to provide a satisfactory surface. Using honing
oil C-3501-3880, or a light honing oil, available from
major oil distributors.
CAUTION: DO NOT use engine or transmission oil,
mineral spirits, or kerosene.
(3) Honing should be done by moving the hone up
and down fast enough to get a crosshatch pattern.
The hone marks should INTERSECT at 50É to 60É
for proper seating of rings (Fig. 3).
(4) A controlled hone motor speed between 200 and
300 RPM is necessary to obtain the proper cross-hatch angle. The number of up and down strokes per
minute can be regulated to get the desired 50É to 60É
angle. Faster up and down strokes increase the cross-
hatch angle.
(5) After honing, it is necessary that the block be
cleaned to remove all traces of abrasive. Use a brush
to wash parts with a solution of hot water and deter-
gent. Dry parts thoroughly. Use a clean, white, lint-
free cloth to check that the bore is clean. Oil the
bores after cleaning to prevent rusting.
Fig. 3 Cylinder Bore Crosshatch Pattern
1 - CROSSHATCH PATTERN
2 - INTERSECT ANGLE
BR/BEENGINE 8.0L 9 - 65
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)

DESCRIPTION SPECIFICATION
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 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.)
HYDRAULIC TAPPETS
Body Diameter 22.949 ± 22.962 mm
(0.9035 ± 0.9040 in.)
Clearance (to bore) 0.0203 ± 0.0610 mm
(0.0008 ± 0.0024 in.)
Dry Lash 1.524 ± 5.334 mm
(0.060 ± 0.210 in.)
Push Rod Length 195.52 ± 196.02 mm
(7.698 ± 7.717 in.)
OIL PRESSURE
Curb Idle (Min.*) 83 kPa (12 psi)
@ 3000 rpm 345 ± 414 kPa (50 ± 60
psi)
* If oil pressure is zero at curb idle, DO NOT RUN
ENGINE.
OIL PUMP
Clearance over Rotors
(Max.)0.1906 mm (0.0075 in.)
Cover Out of Flat (Max.) 0.051 mm (0.002 in.)
Inner Rotor Thickness
(Min.)14.925 ± 14.950 mm
(0.5876 ± 0.5886 in.)DESCRIPTION SPECIFICATION
Outer Rotor
Clearance (Max.) 0.1626 mm (0.006 in.)
Diameter (Min.) 82.461 mm (3.246 in.)
Thickness (Min.) 14.925 mm (0.5876 in.)
Tip Clearance between
Rotors
(Max.) 0.584 mm (0.0230 in.)
PISTONS
Clearance at Top of Skirt 0.013 ± 0.038 mm
(0.0005 ± 0.0015 in.)
Piston Length 82.5 mm (3.25 in.)
Piston Ring Groove
Depth
#1&2 91.30 ± 91.55 mm
(3.594 ± 3.604 in.)
#3 92.90 ± 93.15 mm
(3.657 ± 3.667 in.)
Weight 463 ± 473 grams (16.33
± 16.68 oz.)
Piston to Bore Clearance 0.013 ± 0.038 mm
(0.0005 ± 0.0015 in.)
Service Limit 0.0762 mm (0.003 in.)
PISTON PINS
Clearance in Piston 0.010 ± 0.020 mm
(0.0004 ± 0.0008 in.)
Diameter 24.996 ± 25.001 mm
(0.9841 ± 0.9843 in.)
End Play NONE
Length 67.8 ± 68.3 mm
(2.67 ± 2.69 in.)
PISTON RINGS
Ring Gap
Compression Rings 0.254 ± 0.508 mm
(0.010 ± 0.020 in.)
Oil Control (Steel Rails) 0.381 ± 1.397 mm
(0.015 ± 0.055 in.)
9 - 70 ENGINE 8.0LBR/BE
ENGINE 8.0L (Continued)

DESCRIPTION N´m Ft. In.
Drive Plate to CrankshaftÐ
Bolts75 55 Ð
Drive Plate to Torque
ConverterÐ47 35 Ð
Bolts
EGR TubeÐNut 34 25 Ð
EGR ValveÐBolts 20 Ð 174
Engine Support Bracket/
InsulatorÐ68 50 Ð
Through Bolt
Engine Support Bracket/
Insulator to47 35 Ð
BlockÐBolts
Exhaust Manifold to Cylinder
HeadÐ22 16 Ð
Bolt
Generator MountingÐBolt 41 30 Ð
Generator to Intake Manifold
Bracket41 30 Ð
ÐBolts
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 28 21 Ð
Spark Plugs 41 30 Ð
Starter MountingÐBolts 68 50 ÐDESCRIPTION N´m Ft. In.
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
Bolts
SPECIAL TOOLS
8.0L ENGINE
Valve Compressor Adapting Stud Tool 6715
Valve Spring Compressor Adapter Tool 6716A
9 - 72 ENGINE 8.0LBR/BE
ENGINE 8.0L (Continued)