(5) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
(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. 83)
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.
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. 84) hand
tighten filter one full turn, do not over tighten.
(3) Add oil, verify crankcase oil level and start
engine. Inspect for oil leaks.
Fig. 82 Oil Pump And Primary Timing Chain
Tensioner Tightening SequenceFig. 83 OIL FILTER
1 - ENGINE OIL FILTER
Fig. 84 Oil Filter Sealing Surface-Typical
1 - SEALING SURFACE
2 - RUBBER GASKET
3 - OIL FILTER
9 - 70 ENGINE - 3.7LDR
OIL PUMP (Continued)
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. 88) 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.
Fig. 88 Intake Manifold
1 - THROTTLE BODY
2 - INTAKE MANIFOLD
3 - INTAKE PORT GASKETS
9 - 72 ENGINE - 3.7LDR
OIL (Continued)
(1) Start the engine.
(2) Spray a small stream of water (spray bottle) at
the suspected leak area.
(3) If engine RPM'S change, the area of the sus-
pected leak has been found.
(4) Repair as required.
REMOVAL
(1) Disconnect negative cable from battery.
(2) Remove resonator assembly and air inlet hose.
(3) Disconnect throttle and speed control cables.
(4) Disconnect electrical connectors for the follow-
ing components: Refer to FUEL SYSTEM for compo-
nent locations.
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
(5) Disconnect vapor purge hose, brake booster
hose, speed control servo hose, positive crankcase
ventilation (PCV) hose.
(6) Disconnect generator electrical connections.
(7) Disconnect air conditioning compressor electri-
cal connections.
(8) Disconnect left and right radio suppressor
straps.
(9) Disconnect and remove ignition coil towers.
(10) Remove top oil dipstick tube retaining bolt
and ground strap.
(11) Bleed fuel system (Refer to 14 - FUEL SYS-
TEM/FUEL DELIVERY - STANDARD PROCE-
DURE).
(12) Remove fuel rail.
(13) Remove throttle body assembly and mounting
bracket.
(14) Drain cooling system below coolant tempera-
ture level (Refer to 7 - COOLING - STANDARD
PROCEDURE).
(15) Remove the heater hoses from the engine
front cover and the heater core.
(16) Unclip and remove heater hoses and tubes
from intake manifold.
(17) Remove coolant temperature sensor (Refer to
7 - COOLING/ENGINE/ENGINE COOLANT TEMP
SENSOR - REMOVAL).
(18) Remove intake manifold retaining fasteners in
reverse order of tightening sequence.
(19) Remove intake manifold.
INSTALLATION
(1) Install intake manifold gaskets.
(2) Install intake manifold.
(3) Install intake manifold retaining bolts and
tighten in sequence shown in to 12 N´m (105 in. lbs.)
(Fig. 89).(4) Install left and right radio suppressor straps.
(5) Install throttle body assembly.
(6) Connect throttle cable and speed control cable
to throttle body.
(7) Install fuel rail.
(8) Install ignition coil towers.
(9) Position and install heater hoses and tubes
onto intake manifold.
(10) Install the heater hoses to the heater core and
engine front cover.
(11) Connect electrical connectors for the following
components:
²Manifold Absolute Pressure (MAP) Sensor
²Intake Air Temperature (IAT) Sensor
²Throttle Position (TPS) Sensor
²Coolant Temperature (CTS) Sensor
²Idle Air Control (IAC) Motor
²Ignition coil towers
²Fuel injectors
(12) Install top oil dipstick tube retaining bolt and
ground strap.
(13) Connect generator electrical connections.
(14) Connect Vapor purge hose, Brake booster
hose, Speed control servo hose, Positive crankcase
ventilation (PCV) hose.
(15) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(16) Install resonator assembly and air inlet hose.
(17) Connect negative cable to battery.
Fig. 89 Intake Manifold Tightening Sequence
DRENGINE - 3.7L 9 - 73
INTAKE MANIFOLD (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. 94) and a counterbalance
shaft drive.
OPERATION
The primary timing chain is a single inverted tooth
chain type. The primary chain drives the large 50
tooth 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.
The idler shaft is a light press-fit into the cylinder
Fig. 94 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
9 - 76 ENGINE - 3.7LDR
block. A large washer on the idler shaft bolt and the
rear flange of the idler shaft are used to control
sprocket thrust movement. Pressurized oil is routed
through the center of the idler shaft to provide lubri-
cation for the two bushings used in the idler sprocket
assembly.
There are two secondary drive chains, both are
roller type, one to drive the camshaft in each SOHC
cylinder head. There are no shaft speed changes in
the secondary chain drive system. Each secondary
chain drives a 26 tooth cam sprocket directly from
the 26 tooth sprocket on the idler sprocket assembly.
A fixed chain guide and a hydraulic oil damped ten-
sioner are used to maintain tension in each second-
ary chain system. The hydraulic tensioners for the
secondary chain systems are fed pressurized oil from
oil reservoir pockets in the block. Each tensioner
incorporates a controlled leak path through a device
known as a vent disc located in the nose of the piston
to manage chain loads. Each tensioner also has a
mechanical ratchet system that limits chain slack if
the tensioner piston bleeds down after engine shut
down. The tensioner arms and guides also utilize
nylon wear faces for low friction and long wear. The
secondary timing chains receive lubrication from a
small orifice in the tensioners. This orifice is pro-
tected from clogging by a fine mesh screen which is
located on the back of the hydraulic tensioners.
STANDARD PROCEDURE
MEASURING TIMING CHAIN WEAR
NOTE: This procedure must be performed with the
timing chain cover removed.
(1) Remove the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT/CHAIN
AND SPROCKETS - REMOVAL).
(2) To determine if the secondary timing chains
are worn, rotate the engine clockwise until maximum
tensioner piston extension is obtained. Measure the
distance between the secondary timing chain ten-
sioner housing and the step ledge on the piston. The
measurement at point (A) must be less than 15mm
(.5906 inches) (Fig. 95).
(3) If the measurement exceeds the specification
the secondary timing chains are worn and require
replacement (Refer to 9 - ENGINE/VALVE TIMING/
TIMING BELT/CHAIN AND SPROCKETS -
REMOVAL).
SERVICE PROCEDURE - TIMING VERIFICATION
CAUTION: The 3.7L is a non free-wheeling design
engine. Therefore, correct engine timing is critical.
NOTE: Components referred to as left hand or right
hand are as viewed from the drivers position inside
the vehicle.
NOTE: The blue link plates on the chains and the
dots on the camshaft drive sprockets may not line
up during the timing verification procedure. The
blue link plates are lined up with the sprocket dots
only when re-timing the complete timing drive.
Once the timing drive is rotated blue link-to-dot
alignment is no longer valid.
Engine base timing can be verified by the following
procedure:
(1) Remove the cylinder head covers. Refer to the
procedure in this section.
Fig. 95 Measuring Secondary Timing Chains For
Wear
1 - SECONDARY TENSIONER ARM
2 - SECONDARY CHAIN TENSIONER PISTON
DRENGINE - 3.7L 9 - 77
VALVE TIMING (Continued)
must be within 0.10 -0.25 mm (0.004 - 0.010 in.). If
not within specification, the idler gear must be
replaced (Fig. 116).
(21) Install timing chain cover and crankshaft
damper. Refer to procedures.
(22) Install cylinder head covers(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
NOTE: Before installing threaded plug in right cylin-
der head, the plug must be coated with sealant to
prevent leaks.(23) Coat the large threaded access plug with
MopartThread Sealant with Teflon, then install
into the right cylinder head and tighten to 81 N´m
(60 ft. lbs.).
(24) Install the oil fill housing.
(25) Install access plug in left cylinder head.
(26) Install power steering pump(Refer to 19 -
STEERING/PUMP - INSTALLATION).
(27) Fill cooling system(Refer to 7 - COOLING -
STANDARD PROCEDURE).
(28) Connect negative cable to battery.
Fig. 115 TIGHTENING RIGHT SIDE CAMSHAFT
SPROCKET BOLT
1 - TORQUE WRENCH
2 - SPECIAL TOOL 6958 WITH ADAPTER PINS 8346
3 - LEFT CAMSHAFT SPROCKET
4 - RIGHT CAMSHAFT SPROCKETFig. 116 MEASURING IDLER GEAR END PLAY
1 - IDLER SPROCKET ASSEMBLY
2 - DIAL INDICATOR
DRENGINE - 3.7L 9 - 87
TIMING BELT/CHAIN AND SPROCKETS (Continued)
ENGINE - 4.7L
TABLE OF CONTENTS
page page
ENGINE - 4.7L
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - PERFORMANCE...........90
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - MECHANICAL.............92
DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION PRESSURE.............93
DIAGNOSIS AND TESTING - CYLINDER
COMBUSTION PRESSURE LEAKAGE......93
DIAGNOSIS AND TESTING - ENGINE
DIAGNOSIS - INTRODUCTION...........94
STANDARD PROCEDURE
STANDARD PROCEDURE - REPAIR
DAMAGED OR WORN THREADS.........94
STANDARD PROCEDURE - FORM-IN-
PLACE GASKETS AND SEALERS.........94
REMOVAL.............................95
INSTALLATION.........................97
SPECIFICATIONS
SPECIFICATIONS - 4.7L ENGINE.........99
TORQUE...........................102
SPECIAL TOOLS
4.7L ENGINE........................103
AIR CLEANER ELEMENT
REMOVAL............................107
INSTALLATION........................107
CYLINDER HEAD
DESCRIPTION
DESCRIPTION - CYLINDER HEAD.......107
DESCRIPTION - VALVE GUIDES.........107
REMOVAL
REMOVAL - LEFT CYLINDER HEAD......108
REMOVAL - RIGHT CYLINDER HEAD.....110
CLEANING...........................111
INSPECTION..........................111
INSTALLATION
INSTALLATION - LEFT CYLINDER HEAD . . . 112
INSTALLATION - RIGHT CYLINDER HEAD . 113
CAMSHAFT(S) - LEFT
DESCRIPTION........................114
REMOVAL............................115
INSTALLATION........................116
CAMSHAFT(S) - RIGHT
DESCRIPTION........................119
REMOVAL............................119
INSTALLATION........................120
CYLINDER HEAD COVER(S)
DESCRIPTION........................122REMOVAL
REMOVAL - RIGHT SIDE...............122
REMOVAL - LEFT SIDE................122
CLEANING...........................123
INSTALLATION
INSTALLATION - RIGHT SIDE...........123
INSTALLATIONÐLEFT SIDE............123
INTAKE/EXHAUST VALVES & SEATS
DESCRIPTION........................123
REMOVAL............................124
INSTALLATION........................124
ROCKER ARM / ADJUSTER ASSEMBLY
DESCRIPTION........................125
DIAGNOSIS AND TESTING - HYDRAULIC
LASH ADJUSTER.....................125
REMOVAL............................126
INSTALLATION........................126
VALVE SPRINGS
DESCRIPTION........................126
REMOVAL............................126
INSTALLATION........................127
VALVE STEM SEALS
DESCRIPTION........................127
ENGINE BLOCK
DESCRIPTION........................128
STANDARD PROCEDURE - CYLINDER BORE
HONING...........................128
CLEANING...........................128
INSPECTION.........................128
CONNECTING ROD BEARINGS
STANDARD PROCEDURE - CONNECTING
ROD BEARING FITTING...............129
CORE PLUGS
REMOVAL............................131
INSTALLATION........................131
CRANKSHAFT
DESCRIPTION........................131
REMOVAL............................131
INSPECTION.........................132
INSTALLATION........................132
CRANKSHAFT MAIN BEARINGS
STANDARD PROCEDUREÐCRANKSHAFT
MAIN BEARING - FITTING..............134
INSPECTION.........................135
CRANKSHAFT OIL SEAL - FRONT
REMOVAL............................135
INSTALLATION........................136
9 - 88 ENGINE - 4.7LDR
CRANKSHAFT OIL SEAL - REAR
DIAGNOSIS AND TESTING - REAR SEAL
AREA LEAKS........................137
REMOVAL............................137
INSTALLATION........................138
FLEX PLATE
REMOVAL............................138
INSTALLATION........................138
PISTON & CONNECTING ROD
DESCRIPTION........................139
STANDARD PROCEDURE - PISTON FITTING . 139
REMOVAL............................139
CLEANING...........................140
INSPECTION.........................140
INSTALLATION........................140
PISTON RINGS
STANDARD PROCEDURE - PISTON RING
FITTING............................142
VIBRATION DAMPER
REMOVAL............................144
INSTALLATION........................144
STRUCTURAL COVER
DESCRIPTION........................145
OPERATION..........................145
REMOVAL............................145
INSTALLATION........................145
FRONT MOUNT
REMOVAL............................146
INSTALLATION........................147
REAR MOUNT
REMOVAL............................149
INSTALLATION........................149
LUBRICATION
DESCRIPTION........................150
OPERATION..........................150
DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTING - CHECKING
ENGINE OIL PRESSURE...............152
DIAGNOSIS AND TESTING - ENGINE OIL
LEAK..............................152
OIL
STANDARD PROCEDURE - ENGINE OIL
SERVICE...........................153
OIL FILTER
REMOVAL............................154
INSTALLATION........................155
OIL PAN
REMOVAL............................155
INSTALLATION........................155OIL PRESSURE SENSOR/SWITCH
DESCRIPTION
DESCRIPTION.......................156
DESCRIPTION.......................156
OPERATION
OPERATION........................156
OPERATION........................156
REMOVAL............................156
INSTALLATION........................156
OIL PUMP
REMOVAL............................156
DISASSEMBLY........................157
CLEANING...........................157
INSPECTION.........................157
ASSEMBLY...........................158
INSTALLATION........................159
INTAKE MANIFOLD
DESCRIPTION........................159
DIAGNOSIS AND TESTINGÐINTAKE
MANIFOLD LEAKAGE.................159
REMOVAL............................159
CLEANING...........................160
INSPECTION.........................160
INSTALLATION........................160
EXHAUST MANIFOLD
DESCRIPTION........................161
REMOVAL............................161
CLEANING...........................163
INSPECTION.........................163
INSTALLATION........................164
VALVE TIMING
DESCRIPTIONÐTIMING DRIVE SYSTEM....166
OPERATION - TIMING DRIVE SYSTEM.....166
STANDARD PROCEDURE
STANDARD PROCEDUREÐMEASURING
TIMING CHAIN WEAR.................167
STANDARD PROCEDURE - ENGINE TIMING
- VERIFICATION.....................167
TIMING BELT / CHAIN COVER(S)
REMOVAL............................170
INSTALLATION........................171
TIMING BELT/CHAIN AND SPROCKETS
REMOVAL............................172
INSPECTION.........................174
INSTALLATION........................176
IDLER SHAFT
REMOVAL............................179
INSTALLATION........................179
DRENGINE - 4.7L 9 - 89