oil type DODGE RAM 2003 Service Owner's Guide

DIAGNOSIS & TESTING - RELAY CIRCUIT TEST
(1) The relay common feed terminal cavity (30) of
the integrated power module is connected to battery
voltage and should be hot at all times. Check for bat-
tery voltage at the fused B(+) circuit cavity in the
integrated power module receptacle for the relay. If
OK, go to Step 2. If not OK, repair the fused B(+) cir-
cuit to the integrated power module fuse as required.
(2) The relay normally closed terminal (87A) is
connected to terminal 30 in the de-energized position,
but is not used for this application. Go to Step 3.
(3) The relay normally open terminal (87) is con-
nected to the common feed terminal (30) in the ener-
gized position. This terminal supplies battery voltage
to the fused B(+) fuse in the integrated power module
that feeds the accessory when the relay is energized
by the ignition switch. There should be continuity
between the integrated power module cavity for relay
terminal 87 and the fused B(+) fuse in the integrated
power module at all times. If OK, go to Step 4. If not
OK, repair the open fused B(+) circuit to the inte-
grated power module fuse as required.
(4) The coil ground terminal (85) is connected to
the electromagnet in the relay. It receives battery
feed to energize the relay when the ignition switch is
in the Accessory or Run positions. Turn the ignition
switch to the On position. Check for battery voltage
at the fused ignition switch output (acc/run) circuit
cavity for relay terminal 85 in the integrated power
module receptacle for the relay. If OK, go to Step 5. If
not OK, repair the open fused ignition switch output
(acc/run) circuit to the ignition switch as required.
(5) The coil battery terminal (86) is connected to
the electromagnet in the relay. The integrated power
module cavity for this terminal should have continu-
ity to ground at all times. If not OK, repair the open
ground circuit to ground as required.
REMOVAL
(1) Disconnect and isolate the negative battery
cable.
(2) Remove the relay by grasping it firmly and
pulling it straight out from its receptacle. A slight
back and fourth rocking motion may help the
removal process.
INSTALLATION
(1) Position the relay to the proper receptacle.
(2) Align the relay terminals with the terminal
cavities in the receptacle.
(3) Push firmly and evenly on the top of the relay
until the terminals are fully seated in the terminal
cavities in the receptacle.
(4) Connect the negative battery cable.
MICRO RELAY
DESCRIPTION
A micro-relay is a conventional International Stan-
dards Organization (ISO) micro relay (Fig. 9). Relays
conforming to the ISO specifications have common
physical dimensions, current capacities, terminal pat-
terns, and terminal functions. The relay is contained
within a small, rectangular, molded plastic housing
and is connected to all of the required inputs and
outputs by five integral male spade-type terminals
that extend from the bottom of the relay base.
Relays cannot be adjusted or repaired and, if faulty
or damaged, the unit must be replaced.
OPERATION
A micro-relay is an electromechanical switch that
uses a low current input from one source to control a
high current output to another device. The movable
common feed contact point is held against the fixed
normally closed contact point by spring pressure.
When the relay coil is energized, an electromagnetic
field is produced by the coil windings. This electro-
magnetic field draws the movable relay contact point
away from the fixed normally closed contact point,
and holds it against the fixed normally open contact
point. When the relay coil is de-energized, spring
pressure returns the movable contact point back
against the fixed normally closed contact point. A
resistor is connected in parallel with the relay coil in
the relay, and helps to dissipate voltage spikes and
electromagnetic interference that can be generated as
the electromagnetic field of the relay coil collapses.
DIAGNOSIS AND TESTING - MICRO-RELAY
(1) Remove the relay from its mounting location.
(2) A relay in the de-energized position should
have continuity between terminals 87A and 30, and
Fig. 9 DR ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
DR8W-97 POWER DISTRIBUTION 8W - 97 - 9
RELAY (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.
Inspect valve springs. Replace as
necessary.
AIR ESCAPES THROUGH
TAILPIPEExhaust valve bent, burnt, or not
seated properlyInspect valve and valve seat.
Reface or replace, as necessary.
Inspect valve springs. 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 PROCEDURE - REPAIR DAMAGED
OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain
the original center line.
Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
STANDARD PROCEDURE - FORM-IN-PLACE
GASKETS AND SEALERS
There are numerous places where form-in-place
gaskets are used on the engine. Care must be taken
when applying form-in-place gaskets to assure
obtaining the desired results.Do not use form-in-
place gasket material unless specified.Bead size,
continuity, and location are of great importance. Too
thin a bead can result in leakage while too much can
result in spill-over which can break off and obstruct
fluid feed lines. A continuous bead of the proper
width is essential to obtain a leak-free gasket.
There are numerous types of form-in-place gasket
materials that are used in the engine area. Mopart
Engine RTV GEN II, MopartATF-RTV, and MopartGasket Maker gasket materials, each have different
properties and can not be used in place of the other.
MOPARtENGINE RTV GEN II
MopartEngine RTV GEN II is used to seal com-
ponents exposed to engine oil. This material is a spe-
cially designed black silicone rubber RTV that
retains adhesion and sealing properties when
exposed to engine oil. Moisture in the air causes the
material to cure. This material is available in three
ounce tubes and has a shelf life of one year. After one
year this material will not properly cure. Always
inspect the package for the expiration date before
use.
MOPARtATF RTV
MopartATF RTV is a specifically designed black
silicone rubber RTV that retains adhesion and seal-
ing properties to seal components exposed to auto-
matic transmission fluid, engine coolants, and
moisture. This material is available in three ounce
tubes and has a shelf life of one year. After one year
this material will not properly cure. Always inspect
the package for the expiration date before use.
MOPARtGASKET MAKER
MopartGasket Maker is an anaerobic type gasket
material. The material cures in the absence of air
when squeezed between two metallic surfaces. It will
not cure if left in the uncovered tube. The anaerobic
material is for use between two machined surfaces.
Do not use on flexible metal flanges.
MOPARtGASKET SEALANT
MopartGasket Sealant is a slow drying, perma-
nently soft sealer. This material is recommended for
sealing threaded fittings and gaskets against leakage
DRENGINE - 3.7L 9 - 9
ENGINE - 3.7L (Continued)

(17) Connect the engine to body ground straps at
the left side of the cowl.
(18) Install the intake manifold.
(19) Install the engine oil dipstick tube.
(20) Install the power brake booster vacuum hose.
(21) Install the breather hoses.
(22) Install the PCV hose.
(23) Install the fuel rail.
(24) Install the coil over plugs.
(25) Connect the engine wiring harness at the fol-
lowing points:
²Intake air temperature (IAT) sensor
²Fuel Injectors
²Throttle Position (TPS) Switch
²Idle Air Control (IAC) Motor
²Engine Oil Pressure Switch
²Engine Coolant Temperature (ECT) Sensor
²Manifold Absolute Pressure MAP) Sensor
²Camshaft Position (CMP) Sensor
²Coil Over Plugs
²Crankshaft Position Sensor
(26) Reinstall the radiator/cooling module assem-
bly.
(27) Connect lower radiator hose.
(28) Connect upper radiator hose.
(29) Connect throttle and speed control cables.
(30) Install the heater hose assembly.
(31) Install coolant recovery bottle.
(32) Install the power steering pump.
(33) Install the generator.
(34) Install the A/C compressor.
(35) Install the drive belt.
(36) Install the fan shroud with the viscous fan
assembly.
(37) Install the radiator core support bracket.
(38) Install the air cleaner assembly.
(39) Refill the engine cooling system.
(40) Recharge the air conditioning.
(41) Install the hood.
(42) Check and fill engine oil.
(43) Connect the battery negative cable.
(44) Start the engine and check for leaks.SPECIFICATIONS
SPECIFICATIONS ± 3.7L ENGINE
DESCRIPTION SPECIFICATION
Engine Type 90É SOHC V-6 12-Valve
Displacement 3.7 Liters / 3700 cc
226 ( Cubic Inches)
Bore 93.0 mm (3.66 in.)
Stroke 90.8 mm (3.40 in.)
Compression Ratio 9.1:1
Horsepower 210 BHP @ 5200 RPM
Torque 225 LB-FT @ 4200 RPM
Lead Cylinder #1 Left Bank
Firing Order 1-6-5-4-3-2
CYLINDER BLOCK
Cylinder Block Cast Iron
Bore Diameter 93.0   .0075 mm
(3.6619   0.0003 in.)
Out of Round (MAX) 0.076 mm (0.003 in.)
Taper (MAX) 0.051 mm (0.002 in.)
PISTONS
Material Aluminum Alloy
Diameter 92.975 mm (3.6605 in.)
Weight 367.5 grams (12.96 oz)
Ring Groove Diameter
No. 1 83.73 - 83.13 mm
(3.296 - 3.273 in.)
No. 2 82.833 - 83.033 mm
(3.261 - 3.310 in.)
No. 3 83.88 - 84.08 mm
(3.302 - 3.310 in.)
PISTON PINS
Type Floating
Clearance In Piston 0.006 - 0.015 mm
(0.0002 - 0.0005 in.)
Diameter 24.017 - 24.020 mm
(0.9455 - 0.9456 in.)
PISTON RINGS
Ring Gap
Top Compression Ring 0.20 - 0.36 mm
(0.0079 - 0.0142 in.)
9 - 12 ENGINE - 3.7LDR
ENGINE - 3.7L (Continued)

VALVE GUIDE SEALS
DESCRIPTION
The valve guide seals are made of rubber and
incorporate an integral steel valve spring seat. The
integral garter spring maintains consistent lubrica-
tion control to the valve stems.
VALVE SPRINGS
DESCRIPTION
The valve springs are made from high strength
chrome silicon steel. The springs are NOT common
for intake and exhaust applications. The valve spring
seat is integral with the valve stem seal, which is a
positive type seal to control lubrication.
REMOVAL
(1) Remove the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(2) Using Special Tool 8516 Valve Spring Compres-
sor, remove the rocker arms and the hydraulic lash
adjusters.
(3) Remove the spark plug for the cylinder the
valve spring and seal are to be removed from.
(4) Apply shop air to the cylinder to hold the
valves in place when the spring is removed.
NOTE: All six valve springs and seals are removed
in the same manner; this procedure only covers
one valve seal and valve spring.
(5) Using Special Tool 8387 Valve Spring Compres-
sor, compress the valve spring.
NOTE: It may be necessary to tap the top of the
valve spring to loosen the spring retainers locks
enough to be removed.
(6) Remove the two spring retainer lock halves.
NOTE: the valve spring is under tension use care
when releasing the valve spring compressor.
(7) Remove the valve spring compressor.
NOTE: The valve springs are NOT common between
intake and exhaust.
(8) Remove the spring retainer, and the spring.
(9) Remove the valve stem seal.
NOTE: The valve stem seals are common between
intake and exhaust.
INSTALLATION
NOTE: All six valve springs and seals are removed
in the same manner; this procedure only covers
one valve seal and valve spring.
(1) Apply shop air to the cylinder to hold the
valves in place while the spring is installed.
NOTE: The valve stem seals are common between
intake and exhaust.
(2) Install the valve stem seal.
NOTE: The valve springs are NOT common between
intake and exhaust.
(3) Install the spring retainer, and the spring.
(4) Using Special Tool 8387 Valve Spring Compres-
sor, compress the valve spring.
(5) Install the two spring retainer lock halves.
NOTE: the valve spring is under tension use care
when releasing the valve spring compressor.
(6) Remove the valve spring compressor.
(7) Disconnect the shop air to the cylinder.
(8) Install the spark plug for the cylinder the valve
spring and seal was installed on.
(9) Using Special Tool 8516 Valve Spring Compres-
sor, install the rocker arms and the hydraulic lash
adjusters.
(10) Install the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
CYLINDER HEAD - RIGHT
DIAGNOSIS AND TESTING - HYDRAULIC LASH
ADJUSTER
A tappet-like noise may be produced from several
items. Check the following items.
(1) Engine oil level too high or too low. This may
cause aerated oil to enter the adjusters and cause
them to be spongy.
(2) Insufficient running time after rebuilding cylin-
der head. Low speed running up to 1 hour may be
required.
(3) Turn engine off and let set for a few minutes
before restarting. Repeat this several times after
engine has reached normal operating temperature.
(4) Low oil pressure.
(5) The oil restrictor in cylinder head gasket or the
oil passage to the cylinder head is plugged with
debris.
DRENGINE - 3.7L 9 - 31

(12) Remove cylinder head cover retaining bolts.
(13) Remove cylinder head cover.
INSTALLATION
CAUTION: Do not use harsh cleaners to clean the
cylinder head covers. Severe damage to covers
may occur.
NOTE: The gasket may be used again, provided no
cuts, tears, or deformation has occurred.
(1) Clean cylinder head cover and both sealing sur-
faces. Inspect and replace gasket as necessary.
(2) Tighten cylinder head cover bolts and double
ended studs to 12 N´m (105 in. lbs).
(3) Install right rear breather tube and filter
assembly.
(4) Connect injector, ignition coil electrical connec-
tors and harness retaining clips.
(5) Install the oil fill tube.
(6) Install PCV hose.
(7) Install heater hoses.
(8) Install air conditioning compressor retaining
bolts.
(9) Install accessory drive belt(Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).
(10) Fill Cooling system(Refer to 7 - COOLING -
STANDARD PROCEDURE).
(11) Install air cleaner assembly, resonator assem-
bly and air inlet hose.
(12) Connect battery negative cable.
ROCKER ARM
DESCRIPTION
The rocker arms are steel stampings with an inte-
gral roller bearing. The rocker arms incorporate a 2.8
mm (0.11 inch) oil hole in the lash adjuster socket for
roller and camshaft lubrication.
REMOVAL
NOTE: Disconnect the battery negative cable to pre-
vent accidental starter engagement.
(1) Remove the cylinder head cover (Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(2) For rocker arm removal on cylinder #4, Rotate
the crankshaft until cylinder #1 is at BDC intake
stroke.(3) For rocker arm removal on cylinder #1, Rotate
the crankshaft until cylinder #1 is at BDC combus-
tion stroke.
(4) For rocker arm removal on cylinders #3 and #5,
Rotate the crankshaft until cylinder #1 is at TDC
exhaust stroke.
(5) For rocker arm removal on cylinders #2 and #6,
Rotate the crankshaft until cylinder #1 is at TDC
ignition stroke.
(6) Using special tool 8516 Rocker Arm Remover,
press downward on the valve spring, remove rocker
arm (Fig. 28).
VALVE GUIDE SEALS
DESCRIPTION
The valve guide seals are made of rubber and
incorporate an integral steel valve spring seat. The
integral garter spring maintains consistent lubrica-
tion control to the valve stems.
VALVE SPRINGS
DESCRIPTION
The valve springs are made from high strength
chrome silicon steel. There are different springs for
intake and exhaust applications. The valve spring
seat is integral with the valve stem seal, which is a
positive type seal to control lubrication.
Fig. 28 Rocker Arm - Removal
1 - CAMSHAFT
2 - SPECIAL TOOL 8516
9 - 36 ENGINE - 3.7LDR
CYLINDER HEAD COVER(S) (Continued)

REAR MOUNT
REMOVAL
(1) Raise the vehicle on a hoist.
(2) Using a suitable jack, support transmission.
(3) Remove the nuts from the transmission mount
(Fig. 70).
(4) Remove the two bolts that attach the transmis-
sion mount to the engine bracket.
(5) Raise the transmission enough to remove the
mount from the crossmember.
(6) Remove the mount.
INSTALLATION
NOTE: Threadlocking compound must be applied to
the bolts before installation.(1) Install the two bolts that attach the transmis-
sion mount to the transmission bracket.
(2) Torque the bolts to 61N´m (45 ft.lbs.) torque.
(3) Lower the transmission so the transmission
mount rests on the crossmember, and the studs of
the transmission mount are aligned in the slots in
the crossmember.
(4) Install the nuts onto the transmission mount
studs through the crossmember access slot.
(5) Torque the nuts to 54N´m (40 ft. lbs.).
LUBRICATION
DESCRIPTION
The lubrication system is a full flow filtration pres-
sure feed type.
OPERATION
Oil from the oil pan is pumped by a gerotor type oil
pump directly mounted to the crankshaft nose. Oil
pressure is controlled by a relief valve mounted
inside the oil pump housing. For lubrication flow
refer to (Fig. 71)
The camshaft exhaust valve lobes and rocker arms
are lubricated through a small hole in the rocker
arm; oil flows through the lash adjuster then through
the rocker arm and onto the camshaft lobe. Due to
the orientation of the rocker arm, the camshaft
intake lobes are not lubed in the same manner as the
exhaust lobes. The intake lobes are lubed through
internal passages in the camshaft. Oil flows through
a bore in the number 3 camshaft bearing bore, and
as the camshaft turns, a hole in the camshaft aligns
with the hole in the camshaft bore allowing engine
oil to enter the camshaft tube. The oil then exits
through 1.6mm (0.063 in.) holes drilled into the
intake lobes, lubricating the lobes and the rocker
arms.
Fig. 70 TRANSMISSION MOUNT
1 - MOUNT
2 - CROSSMEMBER
3 - NUT
4 - BOLT
9 - 60 ENGINE - 3.7LDR

(6) Install the pick-up tube and oil pan (Refer to 9
- ENGINE/LUBRICATION/OIL PAN - INSTALLA-
TION).
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 (Fig. 84)
to remove it from the cylinder block oil filter boss.
(4) When filter separates from cylinder block oil
filter boss, tip gasket end upward to minimize oil
spill. Remove filter from vehicle.
Fig. 81 Measuring Clearance Between Rotors
1 - OUTER ROTOR
2 - FEELER GAUGE
3 - INNER ROTOR
Fig. 82 Measuring Clearance Over Rotors
1 - STRAIGHT EDGE
2 - FEELER GAUGE
Fig. 83 Oil Pump And Primary Timing Chain
Tensioner Tightening Sequence
Fig. 84 OIL FILTER
1 - ENGINE OIL FILTER
DRENGINE - 3.7L 9 - 69
OIL PUMP (Continued)

NOTE: Make sure filter gasket was removed with fil-
ter.
(5) With a wiping cloth, clean the gasket sealing
surface of oil and grime.
INSTALLATION
(1) Lightly lubricate oil filter gasket with engine
oil.
(2) Thread filter onto adapter nipple. When gasket
makes contact with sealing surface, (Fig. 85) hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
OIL
STANDARD PROCEDURE - ENGINE OIL
SERVICE
WARNING: NEW OR USED ENGINE OIL CAN BE
IRRITATING TO THE SKIN. AVOID PROLONGED OR
REPEATED SKIN CONTACT WITH ENGINE OIL.
CONTAMINANTS IN USED ENGINE OIL, CAUSED BY
INTERNAL COMBUSTION, CAN BE HAZARDOUS TO
YOUR HEALTH. THOROUGHLY WASH EXPOSED
SKIN WITH SOAP AND WATER. DO NOT WASH
SKIN WITH GASOLINE, DIESEL FUEL, THINNER, OR
SOLVENTS, HEALTH PROBLEMS CAN RESULT. DO
NOT POLLUTE, DISPOSE OF USED ENGINE OIL
PROPERLY.
ENGINE OIL SPECIFICATION
CAUTION: Do not use non-detergent or straight
mineral oil when adding or changing crankcase
lubricant. Engine failure can result.
API SERVICE GRADE CERTIFIED
Use an engine oil that is API Service Grade Certi-
fied. MOPARtprovides engine oils that conform to
this service grade.
SAE VISCOSITY
An SAE viscosity grade is used to specify the vis-
cosity of engine oil. Use only engine oils with multi-
ple viscosities such as 5W-30 or 10W-30 in the 4.7L
engines. These are specified with a dual SAE viscos-
ity grade which indicates the cold-to-hot temperature
viscosity range. Select an engine oil that is best
suited to your particular temperature range and vari-
ation (Fig. 86).
ENERGY CONSERVING OIL
An Energy Conserving type oil is recommended for
gasoline engines. The designation of ENERGY CON-
SERVING is located on the label of an engine oil con-
tainer.
CONTAINER IDENTIFICATION
Standard engine oil identification notations have
been adopted to aid in the proper selection of engine
oil. The identifying notations are located on the label
of engine oil plastic bottles and the top of engine oil
cans (Fig. 87).
Fig. 85 Oil Filter Sealing Surface-Typical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTERFig. 86 TEMPERATURE/ENGINE OIL VISCOSITY -
4.7L ENGINE
Fig. 87 Engine oil Container Standard Notations
9 - 70 ENGINE - 3.7LDR
OIL FILTER (Continued)

OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the right
rear of the engine on the 4.7L engines. (Fig. 88).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
pressure loss or oil foaming can result.
Inspect engine oil level approximately every 800
kilometers (500 miles). Unless the engine has exhib-
ited loss of oil pressure, run the engine for about five
minutes before checking oil level. Checking engine oil
level on a cold engine is not accurate.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
(2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
(6) Add oil only if level is below the ADD mark on
dipstick.
ENGINE OIL CHANGE
Change engine oil at mileage and time intervals
described in Maintenance Schedules.
Run engine until achieving normal operating tem-
perature.
(1) Position the vehicle on a level surface and turn
engine off.
(2) Hoist and support vehicle on safety stands.
(3) Remove oil fill cap.
(4) Place a suitable drain pan under crankcase
drain.
(5) Remove drain plug from crankcase and allow
oil to drain into pan. Inspect drain plug threads for
stretching or other damage. Replace drain plug if
damaged.
(6) Install drain plug in crankcase.
(7) Lower vehicle and fill crankcase with specified
type and amount of engine oil described in this sec-
tion.
(8) Install oil fill cap.
(9) Start engine and inspect for leaks.
(10) Stop engine and inspect oil level.
USED ENGINE OIL DISPOSAL
Care should be exercised when disposing used
engine oil after it has been drained from a vehicle
engine. Refer to the WARNING at beginning of this
section.
INTAKE MANIFOLD
DESCRIPTION
The intake manifold (Fig. 89) is made of a compos-
ite material and features 300 mm (11.811 in.) long
runners which maximizes low end torque. The intake
manifold uses single plane sealing which consist of
six individual press in place port gaskets to prevent
leaks. The throttle body attaches directly to the
intake manifold. Eight studs and two bolts are used
to fasten the intake to the head.
DIAGNOSIS AND TESTING - INTAKE
MANIFOLD LEAKS
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.
Fig. 88 ENGINE OIL DIPSTICK 4.7L ENGINE
1 - TRANSMISSION DIPSTICK
2 - ENGINE OIL DIPSTICK
3 - ENGINE OIL FILL CAP
DRENGINE - 3.7L 9 - 71
OIL (Continued)

VALVE TIMING
DESCRIPTION
The timing drive system has been designed to pro-
vide quiet performance and reliability to support a
non-free wheelingengine. Specifically the intake
valves are non-free wheeling and can be easily dam-
aged with forceful engine rotation if camshaft-to-
crankshaft timing is incorrect. The timing drive
system consists of a primary chain, two secondary
timing chain drives (Fig. 95) and a counterbalance
shaft drive.
OPERATION
The primary timing chain is a single inverted tooth
chain type. The primary chain drives the large 50tooth idler sprocket directly from a 25 tooth crank-
shaft sprocket. Primary chain motion is controlled by
a pivoting leaf spring tensioner arm and a fixed
guide. The arm and the guide both use nylon plastic
wear faces for low friction and long wear. The pri-
mary chain receives oil splash lubrication from the
secondary chain drive and designed oil pump leak-
age. The idler sprocket assembly connects the pri-
mary chain drive, secondary chain drives, and the
counterbalance shaft. The idler sprocket assembly
consists of two integral 26 tooth sprockets a 50 tooth
sprocket and a helical gear that is press-fit to the
assembly. The spline joint for the 50 tooth sprocket is
a non ± serviceable press fit anti rattle type. A spiral
ring is installed on the outboard side of the 50 tooth
sprocket to prevent spline disengagement. The idler
sprocket assembly spins on a stationary idler shaft.
Fig. 95 Timing Drive System
1 - RIGHT CAMSHAFT SPROCKET AND SECONDARY CHAIN
2 - SECONDARY TIMING CHAIN TENSIONER (LEFT AND RIGHT
SIDE NOT INTERCHANGEABLE)
3 - SECONDARY TENSIONER ARM
4 - LEFT CAMSHAFT SPROCKET AND SECONDARY CHAIN
5 - CHAIN GUIDE (LEFT AND RIGHT SIDE ARE NOT
INTERCHANGEABLE)6 - PRIMARY CHAIN
7 - IDLER SPROCKET
8 - CRANKSHAFT SPROCKET
9 - PRIMARY CHAIN TENSIONER
DRENGINE - 3.7L 9 - 75