control arm DODGE RAM 1500 1998 2.G Repair Manual
[x] Cancel search | Manufacturer: DODGE, Model Year: 1998, Model line: RAM 1500, Model: DODGE RAM 1500 1998 2.GPages: 2627
Page 710 of 2627

(7) Reinstall both wiper arms onto the wiper piv-
ots. (Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ARM - INSTALLATION).
WASHER PUMP/MOTOR
DESCRIPTION
The washer pump/motor unit (Fig. 12) is located on
the rearward facing surface of the washer reservoir,
in the right (except diesel engine) or left (diesel
engine only) front corner of the engine compartment.
A small permanently lubricated and sealed electric
motor is coupled to the rotor-type washer pump. A
seal flange with a barbed inlet nipple on the pump
housing passes through a rubber grommet seal
installed in a dedicated mounting hole of the washer
reservoir. When the pump is installed in the reser-
voir a barbed outlet nipple on the pump housing con-
nects the unit to the washer system through a short
washer reservoir hose.
The washer pump/motor unit is retained on the
reservoir by the interference fit between the barbed
pump inlet nipple and the grommet seal, which is a
light press fit. The top of the washer pump is also
secured to the washer reservoir by the use of a snappost on the motor housing and a snap post receptacle
molded into the reservoir that allows for mounting of
the washer pump without the use of fasteners. An
integral connector receptacle on the top of the motor
housing connects the unit to the vehicle electrical
system. The washer pump/motor unit cannot be
repaired. If faulty or damaged, the entire washer
pump/motor unit must be replaced.
OPERATION
The washer pump/motor unit features a small
Direct Current (DC) electric motor. The motor is con-
nected to the vehicle electrical system through a sin-
gle take out and two-cavity connector of the right
(except diesel engine) or left (diesel engine only)
headlamp and dash wire harness. The motor is
grounded at all times through another take out of
the right (except diesel engine) or left (diesel engine
only) headlamp and dash wire harness. On models
without the diesel engine, a single eyelet terminal
connector is secured by a nut to a ground stud
located on the right front fender inner shield in the
engine compartment. On models with a diesel engine,
an eyelet terminal connector is secured by a ground
screw to the left front fender inner shield in the
engine compartment. The motor receives battery cur-
rent on a washer pump/motor control circuit.
The washer pump/motor control circuit is energized
through a high side driver within the Front Control
Module (FCM) whenever the FCM receives an elec-
tronic message requesting washer system operation
from the instrument cluster over the Programmable
Communications Interface (PCI) data bus. The
instrument cluster monitors a resistor multiplexed
hard wired input from the momentary washer switch
contacts within the multi-function switch on the
steering column to determine when it should issue
the electronic message requesting washer system
operation.
Washer fluid is gravity-fed from the washer reser-
voir to the inlet side of the washer pump. When the
pump motor is energized, the motor spins the rotor
within the washer pump. The spinning pump rotor
pressurizes the washer fluid and forces it through
the pump outlet nipple, the washer plumbing, and
the washer nozzles onto the windshield glass.
The washer pump/motor unit may be diagnosed
using conventional diagnostic tools and methods.
However, conventional diagnostic methods may not
prove conclusive in the diagnosis of the instrument
cluster, the FCM, or the electronic message inputs to
or outputs from the instrument cluster and the FCM
that control the operation of the washer pump/motor
unit. The most reliable, efficient, and accurate means
to diagnose the washer pump/motor unit, the instru-
ment cluster, the FCM, or the electronic message
Fig. 12 Washer Pump/Motor
1 - MOTOR
2 - SNAP POST
3 - CONNECTOR RECEPTACLE
4 - PUMP
5 - OUTLET NIPPLE
6 - INLET NIPPLE
7 - FILTER SCREEN
DRWIPERS/WASHERS 8R - 13
WASHER NOZZLE (Continued)
Page 715 of 2627

plenum cover/grille panel near the base of the wind-
shield and the wiper blades on the windshield glass
(Fig. 18). These wiper arms feature an over-center
hinge that allows easy access to the windshield glass
for cleaning. The wiper arm has a die cast metal
pivot end with a large internally serrated socket for-
mation at one end. A key within the socket formation
indexes the wiper arm to a keyway in the pivot shaft
of the wiper module to provide wiper alignment, and
a spring-loaded latch on the underside of the wiper
arm pivot end locks the unit to the pivot shaft when
it is fully installed. The right and left wiper arms for
this model are not interchangeable, as the right
wiper arm is slightly longer than the left one.
The wide end of a tapered, stamped steel channel
hinges on and is secured with a hinge pin to the
blade end of the wiper arm pivot end. One end of a
long, rigid, stamped steel strap, with a small hole
near its pivot end, is riveted and crimped within the
narrow end of the stamped steel channel. The tip of
the wiper blade end of this strap is bent back under
itself to form a small hook. Concealed within the
stamped steel channel, one end of a long spring is
engaged with a wire hook on the underside of the die
cast pivot end, while the other end of the spring is
hooked through the small hole in the steel strap. The
entire wiper arm has a satin black finish applied to
all of its visible surfaces.
A wiper arm cannot be adjusted or repaired. If
damaged or faulty, the entire wiper arm unit must be
replaced.
OPERATION
The wiper arms are designed to mechanically
transmit the motion from the wiper pivots to the
wiper blades. The wiper arm must be properly
indexed to the wiper pivot in order to maintain the
proper wiper blade travel on the glass. The serrated
and keyed socket formation in the wiper arm pivot
end interlocks with the serrations and keyway on the
outer circumference of the wiper pivot shaft, provid-
ing positive engagement and alignment of this con-
nection. The latch positively locks the wiper arm to
the wiper pivot shaft when the arm is fully installed.
The spring-loaded wiper arm hinge controls the
down-force applied through the tip of the wiper arm
to the wiper blade on the glass. The hook formation
on the tip of the wiper arm provides a cradle for
securing and latching the wiper blade pivot block to
the wiper arm.
REMOVAL
(1) Lift the wiper arm to its over-center position to
hold the wiper blade off of the glass and relieve the
spring tension on the wiper arm to wiper pivot shaft
connection.(2) Pull the latch on the pivot end of the wiper
arm outward (Fig. 19).
(3) Remove the wiper arm pivot end from the
wiper pivot shaft.
INSTALLATION
The right and left wiper arms are not interchange-
able. The right wiper arm is slightly longer than the
left. Be certain that each wiper arm is installed on
the proper wiper pivot.
(1) Place the wiper arm hinge in its over-center
position prior to attempting installation.
(2) The wiper arms are indexed to the wiper pivot
shafts with integral keys in the wiper arm pivot ends
and keyways in the wiper pivot shafts. Align the key
of the wiper arm to the keyway on the wiper pivot
shaft.
(3) Once the wiper blade is aligned, push the pivot
of the wiper arm down firmly and evenly over the
wiper pivot shaft until it is fully engaged. When the
wiper arm is fully engaged on the wiper pivot, the
spring-loaded latch (Fig. 19) will snap back into place
against the wiper arm pivot end.
(4) Gently lower the wiper arm until the wiper
blade is in position on the windshield glass.
WIPER BLADE
DESCRIPTION
Each wiper blade is secured by an integral latching
pivot block to the hook formation on the tip of each
wiper arm, and rests on the glass near the base of
the windshield when the wipers are not in operation
(Fig. 20). The wiper blade consists of the following
components:
Fig. 19 Wiper Arm Remove/Install
1 - WIPER ARM PIVOT END
2-LATCH
8R - 18 WIPERS/WASHERSDR
WIPER ARM (Continued)
Page 717 of 2627

INSTALLATION
NOTE: The notched end of the wiper element flexor
should always be oriented towards the end of the
wiper blade that is nearest to the wiper pivot.
(1) Lift the wiper arm off of the windshield glass,
until the wiper arm hinge is in its over-center posi-
tion.
(2) Position the wiper blade near the hook forma-
tion on the tip of the arm with the notched end of the
wiper element flexor oriented towards the end of the
wiper arm that is nearest to the wiper pivot.
(3) Insert the hook formation on the tip of the
wiper arm through the opening in the wiper blade
superstructure ahead of the wiper blade pivot block/
latch unit far enough to engage the pivot block into
the hook (Fig. 21).
(4) Slide the wiper blade pivot block/latch up into
the hook formation on the tip of the wiper arm until
the latch release tab snaps into its locked position.
Latch engagement will be accompanied by an audible
click.
(5) Gently lower the wiper blade onto the glass.
WIPER HIGH/LOW RELAY
DESCRIPTION
The wiper high/low relay is located in the Inte-
grated Power Module (IPM) in the engine compart-
ment near the battery. The wiper high/low relay is a
conventional International Standards Organization
(ISO) micro relay (Fig. 22). Relays conforming to the
ISO specifications have common physical dimensions,
current capacities, terminal patterns, and terminal
functions. The relay is contained within a small, rect-
angular, molded plastic housing and is connected to
all of the required inputs and outputs by five integralmale spade-type terminals that extend from the bot-
tom of the relay base.
The wiper high/low relay cannot be adjusted or
repaired and, if faulty or damaged, the unit must be
replaced.
OPERATION
The wiper high/low relay is an electromechanical
switch that uses a low current input from the Front
Control Module (FCM) to control a high current out-
put to the wiper motor. 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 electromagnetic
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.
The wiper high/low relay terminals are connected
to the vehicle electrical system through a connector
receptacle in the Integrated Power Module (IPM).
The inputs and outputs of the wiper high/low relay
include:
²Common Feed Terminal- The common feed
terminal (30) is connected to the output of the wiper
on/off relay at all times through the wiper on/off
relay output circuit.
²Coil Ground Terminal- The coil ground termi-
nal (85) is connected to a control output of the Front
Control Module (FCM) through a wiper high/low
relay control circuit. The FCM controls wiper motor
operation by controlling a ground path through this
circuit.
²Coil Battery Terminal- The coil battery ter-
minal (86) receives battery current when the ignition
switch is in the On or Accessory positions from a fuse
in the Integrated Power Module (IPM) through a
fused ignition switch output (run-acc) circuit.
²Normally Open Terminal- The normally open
terminal (87) is connected to the high speed brush of
the wiper motor through a wiper high/low relay high
speed output circuit, and is connected to the high
speed brush whenever the relay is energized.
²Normally Closed Terminal- The normally
closed terminal (87A) is connected to the low speed
brush of the wiper motor through a wiper high/low
relay low speed output circuit, and is connected to
the low speed brush whenever the relay is de-ener-
gized.
Fig. 22 ISO Micro Relay
30 - COMMON FEED
85 - COIL GROUND
86 - COIL BATTERY
87 - NORMALLY OPEN
87A - NORMALLY CLOSED
8R - 20 WIPERS/WASHERSDR
WIPER BLADE (Continued)
Page 720 of 2627

OPERATION
The wiper module operation is controlled by the
battery current inputs received by the wiper motor
through the wiper on/off and wiper high/low relays.
The wiper motor speed is controlled by current flow
to either the low speed or the high speed set of
brushes. The park switch is a single pole, single
throw, momentary switch within the wiper motor
that is mechanically actuated by the wiper motor
transmission components. The park switch alter-
nately opens and closes the wiper park switch sense
circuit to ground, depending upon the position of the
wipers on the glass. This feature allows the motor to
complete its current wipe cycle after the wiper sys-
tem has been turned Off, and to park the wiper
blades in the lowest portion of the wipe pattern. The
automatic resetting circuit breaker protects the
motor from overloads. The wiper motor crank arm,
the two wiper linkage members, and the two wiper
pivots mechanically convert the rotary output of the
wiper motor to the back and forth wiping motion of
the wiper arms and blades on the glass.
REMOVAL
(1) Remove both wiper arms from the wiper pivots.
(Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ARM - REMOVAL).
(2) Unlatch and open the hood.
(3) Disconnect and isolate the battery negative
cable.
(4) Remove the cowl plenum cover/grille panel
from over the cowl plenum. (Refer to 23 - BODY/EX-
TERIOR/COWL GRILLE - REMOVAL).
(5) Disconnect the left headlamp and dash wire
harness connector for the wiper motor from the
motor pigtail wire connector (Fig. 26).(6) Remove the two screws that secure the wiper
module to the top of the cowl plenum panel at the
pivot brackets.
(7) Remove the two screws that secure the wiper
module to the bottom of the cowl plenum panel.
(8) Remove the wiper module from the cowl ple-
num panel as a unit.
INSTALLATION
(1) Position the wiper module into the cowl ple-
num as a unit (Fig. 26).
(2) Install the two screws that secure the wiper
module to the top of the cowl plenum panel at the
pivot brackets. Tighten the screw on the driver side,
followed by the screw on the passenger side. Tighten
the screws to 7 N´m (60 in. lbs.).
(3) Install and tighten the screws that secure the
wiper module to the bottom of the cowl plenum
panel. Tighten the screw on the passenger side, fol-
lowed by the screw on the driver side. Tighten the
screws to 7 N´m (60 in. lbs.).
(4) Reconnect the left headlamp and dash wire
harness connector for the wiper motor to the motor
pigtail wire connector.
(5) Reinstall the cowl plenum cover/grille panel
over the cowl plenum. (Refer to 23 - BODY/EXTERI-
OR/COWL GRILLE - INSTALLATION).
(6) Reconnect the battery negative cable.
(7) Close and latch the hood.
(8) Reinstall both wiper arms onto the wiper piv-
ots. (Refer to 8 - ELECTRICAL/WIPERS/WASHERS/
WIPER ARMS - INSTALLATION).
DRWIPERS/WASHERS 8R - 23
WIPER MODULE (Continued)
Page 1219 of 2627

(4) Remove the integrated power module retaining
bolt and screw (Fig. 2).
(5) Grasp the integrated power module with two
hands and slide the assembly in the direction shown
(Fig. 3) to free the module from its mounting bracket.
Position the assembly upside down to access the elec-
trical connectors located on the bottom of the unit.
(6) Disconnect the electrical connectors by depress-
ing the locking tab and rotating the connector arm
outboard, until the connector is free from the module
assembly. Be certain to pull the connectors straight
off.
(7) Position the integrated power module on a
bench and remove the four front control module
retaining screws.
(8) Disconnect the front control module by pulling
it straight off the integrated power module.LLATION
INSTALLATION
(1) Connect the front control module by pushing it
straight on the integrated power module electrical
receptacle.
(2) Install the four front control module retaining
screws. Torque to 30 in. lbs. +/-5.
NOTE: Integrated power module electrical connec-
tors are color coded to ease location reference (Fig.
4).
Fig. 3 REMOVING INTEGRATED POWER MODULE
Fig. 4 INTEGRATED POWER MODULE ELECTRICAL
CONNECTIONS
1 - RETAINING LATCH
2 - GRAY CONNECTOR
3 - GREEN CONNECTOR
4 - GREEN CONNECTOR
5 - BLUE CONNECTOR
6 - WHITE CONNECTOR
7 - BLACK CONNECTOR
8 - BLACK CONNECTOR
8W - 97 - 4 8W-97 POWER DISTRIBUTIONDR
INTEGRATED POWER MODULE (Continued)
Page 1220 of 2627

(3) Connect the electrical connectors by pushing
straight on and rotating the connector arm inboard,
until the connector is firmly locked in place on the
module assembly.
(4) Grasp the integrated power module with two
hands and install the assembly on the battery tray
(Fig. 5).
(5) Install the integrated power module retaining
bolt and screw.
(6) Connect the gray connector on the integrated
power module housing.
(7) Install the B+ terminal cable and nut on the
integrated power module B+ terminal. Snap the
cover in place.
(8) Connect the negative and positive battery
cables.
FRONT CONTROL MODULE
DESCRIPTION
The Front Control Module (FCM) is a micro con-
troller based module located in the left front corner
of the engine compartment. On this model the inte-
grated power module must be positioned aside in
order to access the front control module. The front
control module mates to the power distribution cen-
ter to form the Integrated Power Module (IPM). Theintegrated power module connects directly to the bat-
tery and provides the primary means of circuit pro-
tection and power distribution for all vehicle
electrical systems. The front control module controls
power to some of these vehicle systems electrical and
electromechanical loads based on inputs received
from hard wired switch inputs and data received on
the PCI bus circuit (J1850).
For information on theIntegrated Power Mod-
ule Refer to the Power Distribution Sectionof
the service manual.
OPERATION
As messages are sent over the PCI bus circuit, the
front control module reads these messages and con-
trols power to some of the vehicles electrical systems
by completing the circuit to ground (low side driver)
or completing the circuit to 12 volt power (high side
driver). The following functions areControlledby
the Front Control Module:
²Headlamp Power with Voltage Regulation
²Windshield Wiper ªON/OFFº Relay Actuation
²Windshield Wiper ªHI/LOº Relay Actuation
²Windshield Washer Pump Motor
²Fog Lamp Relay Actuation
²Park Lamp Relay Actuation
²Horn Relay Actuation
The following inputs areReceived/Monitoredby
the Front Control Module:
²B+ Connection Detection
²Power Ground
²Ambient Temperature Sensing
²Ignition Switch Run
²Washer Fluid Level Switch
²Windshield Wiper Park Switch
²PCI Bus Circuit
DIAGNOSIS AND TESTING - FRONT CONTROL
MODULE
The front control module is a printed circuit board
based module with a on-board micro-processor. The
front control module interfaces with other electronic
modules in the vehicle via the Programmable Com-
munications Interface (PCI) data bus (J1850). In
order to obtain conclusive testing the Programmable
Communications Interface (PCI) data bus network
and all of the electronic modules that provide inputs
to, or receive outputs from the front control module
must be checked. All PCI (J1850) communication
faults must be resolved prior to further diagnosing
any front control module related issues.
The front control module was designed to be diag-
nosed with an appropriate diagnostic scan tool, such
as the DRB IIIt. The most reliable, efficient, and
accurate means to diagnose the front control module
Fig. 5 INTEGRATED POWER MODULE MOUNTING
TABS
1 - INTEGRATED POWER MODULE MOUNTING HOLES
2 - BATTERY TRAY ASSEMBLY
3 - FRONT CONTROL MODULE
DR8W-97 POWER DISTRIBUTION 8W - 97 - 5
INTEGRATED POWER MODULE (Continued)
Page 1255 of 2627

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 exhaust
spring has an external damper. The valve spring seat
is integral with the valve stem seal, which is a posi-
tive 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.
9 - 32 ENGINE - 3.7LDR
Page 1261 of 2627

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 exhaust spring
has an external damper. 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).
ENGINE BLOCK
DESCRIPTION
The cylinder block is made of cast iron. The block
is a closed deck design with the left bank forward. To
provide high rigidity and improved NVH an
enhanced compacted graphite bedplate is bolted to
the block. The block design allows coolant flow
between the cylinders bores, and an internal coolant
bypass to a single poppet inlet thermostat is included
in the cast aluminum front cover.
STANDARD PROCEDURE - CYLINDER 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
9 - 38 ENGINE - 3.7LDR
Page 1284 of 2627

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 No. 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
DRENGINE - 3.7L 9 - 61
Page 1285 of 2627

ENGINE LUBRICATION FLOW CHART - BLOCK: TABLE 1
FROM TO
Oil Pickup Tube Oil Pump
Oil Pump Oil Filter
Oil Filter Block Main Oil Gallery
Block Main Oil Gallery 1. Crankshaft Main Journal
2. Left Cylinder Head*
3. Right Cylinder Head*
4. Counterbalance Shaft Rear Journal
Crankshaft Main Journals Crankshaft Rod Journals
Crankshaft Number One Main Journal 1. Front Timing Chain Idler Shaft
2. Counterbalance Shaft - Front Journal
3. Both Secondary Chain Tensioners
Left Cylinder Head Refer to Engine Lubrication Flow Chart - Cylinder
Heads: Table 2
Right Cylinder Head Refer to Engine Lubrication Flow Chart - Cylinder
Heads: Table 2
* The cylinder head gaskets have an oil restricter to control oil flow to the cylinder heads
ENGINE LUBRICATION FLOW CHART - CYLINDER HEADS: TABLE 2
FROM TO
Cylinder Head Oil Port (in bolt hole) Diagonal Cross Drilling to Main Oil Gallery
Main Oil Gallery (drilled through head from rear to
front)1. Base of Camshaft Towers
2. Lash Adjuster Towers
Base of Camshaft Towers Vertical Drilling Through Tower to Camshaft Bearings**
Lash Adjuster Towers Diagonal Drillings to Hydraulic Lash Adjuster Pockets
** The number three camshaft bearing journal feeds oil into the hollow camshaft tubes. Oil is routed to the intake
lobes, which have oil passages drilled into them to lubricate the rocker arms.
9 - 62 ENGINE - 3.7LDR
LUBRICATION (Continued)