wheel DODGE RAM 2003 Service Repair Manual

CONNECTOR NAME/NUMBER COLOR LOCATION FIG.
Powertrain Control Module C2 WT Right Rear Engine Compartment 21, 22, 23, 24
Powertrain Control Module C3 GY Right Rear Engine Compartment 21, 22, 23, 24
Powertrain Control Module C4 GN Right Rear Engine Compartment 21
PTO Sense Near G107 21, 22, 24
Radio (Base) GY Rear of Radio 37, 38
Radio (Premium) BK Rear of Radio 37, 38
Recirculation Door Actuator BK Right Side of HVAC N/S
Red Brake Warning Indicator
SwitchBK Near Master Cylinder 26, 28, 31
Remote Radio Switch-Left BK At Steering Wheel N/S
Remote Radio Switch-Right BK At Steering Wheel N/S
Seat Belt Pretensioner-Left YL Left B-Pillar 44, 45
Seat Belt Pretensioner-Right YL Right B-Pillar N/S
Seat Belt Switch-Driver DK GY Left B-Pillar N/S
Seat Belt Tension Reducer
(Standard Cab)YL Left B-Pillar 44
Seat Heater Interface Module GN Under Driver Seat N/S
Sentry Key Immobilizer Module BK On Steering Column 32
Side Marker - Left Front (Dual
Wheels)BK Front of Left Rear Fender 50
Side Marker - Left Rear (Dual
Wheels)BK Rear of Left Rear Fender 50
Side Marker - Right Front (Dual
Wheels)BK Front of Right Rear Fender 50
Side Marker - Right Rear (Dual
Wheels)BK Rear of Right Rear Fender 50
Speaker-Center Instrument Panel WT Center of Instrument Panel 37, 38
Speaker-Left Front Door WT In Left Front Door 42
Speaker-Left Instrument Panel BK Left Side of Instrument Panel 37, 39
Speaker-Left Rear (Standard Cab) WT In Lower Left B-Pillar 44
Speaker-Left Rear Door (Quad
Cab)WT In Left Rear Door 43
Speaker-Right Front Door WT In Right Front Door N/S
Speaker-Right Instrument Panel BK Right Side of Instrument Panel 37, 40
Speaker-Right Rear (Standard
Cab)BK In Lower Right B-Pillar N/S
Speaker-Right Rear Door (Quad
Cab)BK In Right Rear Door 43
Speed Control Servo BK Left Front Side of Engine
Compartment26, 28
Speed Control Switch - Left
(Except ETC)GN Steering Wheel N/S
Speed Control Switch - Right
(Except ETC)GN Steering Wheel N/S
Speed Control Switch-Left (ETC) WT At Steering Wheel N/S
DR8W-91 CONNECTOR/GROUND/SPLICE LOCATION 8W - 91 - 7
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

CONNECTOR NAME/NUMBER COLOR LOCATION FIG.
Speed Control Switch-Right (ETC) WT At Steering Wheel N/S
Tail/Stop/Turn Signal Lamp-Left BK At Lamp N/S
Tail/Stop/Turn Signal Lamp-Right BK At Lamp N/S
Throttle Position Sensor NAT Throttle Body 4, 8
Trailer Tow Connector BK At Trailer Hitch 49
Trailer Tow Connector-Add On BK At Trailer Hitch 49, 51
Transfer Case Control Module C1 BK Left Side of Instrument Panel 37, 39
Transfer Case Control Module C2 GY Left Side of Instrument Panel 37, 39
Transfer Case Control Module C3 BK Left Side of Instrument Panel 37, 39
Transfer Case Mode Sensor BK Left Front Side of Transfer Case 20
Transfer Case Position Sensor BK Front Middle of Transfer Case 14, 15, 16, 20
Transfer Case Selector Switch BK Center of Instrument Panel 35, 37, 38
Transfer Case Shift Motor BK Left Rear of Transmission 20
Transmission Control Module BK Left Rear of Engine Compartment 21
Transmission Range Sensor BK Left side of Transmission 11, 12
Transmission Solenoid Assembly BK Left Side of Transmission 11, 12
Transmission Solenoid/TRS
Assembly (3.7L/4.7L)BK Left Side of Transmission 14, 15
Underhood Lamp BK Underside of Hood 31
Vistronic Fan Drive Front Engine Compartment 30
Washer Fluid Level Switch BK At Reservoir 25, 29, 30
Washer Pump Motor-Front BK At Washer Fluid Reservoir 25, 29, 30
Water In Fuel Sensor (Diesel) BK Right Side Engine 10
Wheel Speed Sensor-Left Front BK Left Rear Lower Side of Engine
Compartment26, 31
Wheel Speed Sensor-Rear BK Right Rear of Body 49
Wheel Speed Sensor-Right Front GY Right Rear Lower Side of Engine
Compartment25
Wiper Motor-Front BK Left Side of Cowl 26, 28
8W - 91 - 8 8W-91 CONNECTOR/GROUND/SPLICE LOCATIONDR
CONNECTOR/GROUND/SPLICE LOCATION (Continued)

DIAGNOSIS AND TESTING - ENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTIONS
NOISY VALVES 1. High or low oil level in
crankcase.1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Thin or diluted oil. 2. Change oil and filter.
3. Low oil pressure. 3. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
4. Dirt in lash adjusters. 4. Replace as necessary.
5. Worn rocker arms. 5. Replace as necessary.
6. Worn lash adjusters 6. Replace as necessary.
7. Worn valve guides. 7. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
8. Excessive runout of valve seats
on valve faces.8. (Refer to 9 - ENGINE/CYLINDER
HEAD/INTAKE/EXHAUST VALVES
& SEATS - STANDARD
PROCEDURE)
CONNECTING ROD NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Connecting rod journal
out-of-round.5. Service or replace crankshaft.
6. Misaligned connecting rods. 6. Replace bent connecting rods.
MAIN BEARING NOISE 1. Insufficient oil supply. 1. (Refer to LUBRICATION &
MAINTENANCE -
SPECIFICATIONS)
2. Low oil pressure. 2. Check oil pump, if Ok, check rod
and main bearings for excessive
wear.
3. Thin or diluted oil. 3. Change oil and filter.
4. Excessive bearing clearance. 4. Replace as necessary.
5. Excessive end play. 5. Check thrust washers for wear.
6. Crankshaft journal out-of round. 6. Service or replace crankshaft.
7. Loose flywheel or torque
converter.7. Tighten to correct torque
9 - 6 ENGINE - 3.7LDR
ENGINE - 3.7L (Continued)

(3) Mark one link on the secondary timing chain
on both sides of the V6 mark on the camshaft
sprocket to aid in installation.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel (Located on the right side camshaft
sprocket) for any reason, Severe damage will occur
to the target wheel resulting in a vehicle no start
condition.
(4) Loosen butDO NOTremove the camshaft
sprocket retaining bolt. Leave the bolt snug against
the sprocket.
NOTE: The timing chain tensioners must be
secured prior to removing the camshaft sprockets.
Failure to secure tensioners will allow the tension-
ers to extend, requiring timing chain cover removal
in order to reset tensioners.
CAUTION: Do not force wedge past the narrowest
point between the chain strands. Damage to the
tensioners may occur.
(5) Position Special Tool 8379 timing chain wedge
between the timing chain strands, tap the tool to
securely wedge the timing chain against the ten-
sioner arm and guide (Fig. 12).
(6) Hold the camshaft with Special Tool 8428 Cam-
shaft Wrench, while removing the camshaft sprocket
bolt and sprocket (Fig. 13).(7) Using Special Tool 8428 Camshaft Wrench,
gently allow the camshaft to rotate 5É clockwise until
the camshaft is in the neutral position (no valve
load).
(8) Starting at the outside working inward, loosen
the camshaft bearing cap retaining bolts 1/2 turn at
a time. Repeat until all load is off the bearing caps.
CAUTION: DO NOT STAMP OR STRIKE THE CAM-
SHAFT BEARING CAPS. SEVERE DAMAGE WILL
OCCUR TO THE BEARING CAPS.
NOTE: When the camshaft is removed the rocker
arms may slide downward, mark the rocker arms
before removing camshaft.
(9) Remove the camshaft bearing caps and the
camshaft.
INSTALLATION
(1) Lubricate camshaft journals with clean engine
oil.
NOTE: Position the left side camshaft so that the
camshaft sprocket dowel is near the 1 o'clock posi-
tion, This will place the camshaft at the neutral
position easing the installation of the camshaft
bearing caps.
(2) Position the camshaft into the cylinder head.
Fig. 12 SECURING TIMING CHAIN TENSIONERS
USING TIMING CHAIN WEDGE Ð Typical
1 - SPECIAL TOOL 8379
2 - CAMSHAFT SPROCKET
3 - CAMSHAFT SPROCKET BOLT
4 - CYLINDER HEAD
Fig. 13 Special Tool 8428
1 - Camshaft hole
2 - Special Tool 8428
DRENGINE - 3.7L 9 - 25
CAMSHAFT(S) (Continued)

(6) Air ingested into oil due to broken or cracked
oil pump pick up.
(7) Worn valve guides.
(8) Rocker arm ears contacting valve spring
retainer.
(9) Rocker arm loose, adjuster stuck or at maxi-
mum extension and still leaves lash in the system.
(10) Oil leak or excessive cam bore wear in cylin-
der head.
(11) Faulty lash adjuster.
a. Check lash adjusters for sponginess while
installed in cylinder head and cam on camshaft at
base circle. Depress part of rocker arm over adjuster.
Normal adjusters should feel very firm. Spongy
adjusters can be bottomed out easily.
b. Remove suspected lash adjusters, and replace.
c. Before installation, make sure adjusters are at
least partially full of oil. This can be verified by little
or no plunger travel when lash adjuster is depressed.
REMOVAL
(1) Disconnect battery negative cable.
(2) Raise the vehicle on a hoist.
(3) Disconnect the exhaust pipe at the right side
exhaust manifold.
(4) Drain the engine coolant(Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(5) Lower the vehicle.
(6) Remove the intake manifold(Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
REMOVAL).
(7) Remove the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD - REMOVAL).
(8) Remove the fan shroud(Refer to 7 - COOLING/
ENGINE/RADIATOR FAN - REMOVAL).
(9) Remove oil fill housing from cylinder head.
(10) Remove accessory drive belt(Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(11) Rotate the crankshaft until the damper timing
mark is aligned with TDC indicator mark.
(12) Verify the V6 mark on the camshaft sprocket
is at the 12 o'clock position. Rotate the crankshaft
one turn if necessary.
(13) Remove the crankshaft damper(Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(14) Remove the timing chain cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(15) Lock the secondary timing chains to the idler
sprocket using Special Tool 8429 Timing Chain Hold-
ing Fixture.
NOTE: Mark the secondary timing chain prior to
removal to aid in installation.(16) Mark the secondary timing chain, one link on
each side of the V6 mark on the camshaft drive gear.
(17) Remove the right side secondary chain ten-
sioner(Refer to 9 - ENGINE/VALVE TIMING/TIM-
ING BELT/CHAIN AND SPROCKETS - REMOVAL).
(18) Remove the cylinder head access plug.
(19) Remove the right side secondary chain
guide(Refer to 9 - ENGINE/VALVE TIMING/TIMING
BELT/CHAIN AND SPROCKETS - REMOVAL).
CAUTION: The nut on the right side camshaft
sprocket should not be removed for any reason, as
the sprocket and camshaft sensor target wheel is
serviced as an assembly. If the nut was removed
retorque nut to 5 N´m (44 in. lbs.).
(20) Remove the retaining bolt and the camshaft
drive gear.
CAUTION: Do not allow the engine to rotate. severe
damage to the valve train can occur.
CAUTION: Do not overlook the four smaller bolts at
the front of the cylinder head. Do not attempt to
remove the cylinder head without removing these
four bolts.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel for any reason. A damaged target wheel
can result in a vehicle no start condition.
NOTE: The cylinder head is attached to the cylinder
block with twelve bolts.
(21) Remove the cylinder head retaining bolts.
(22) Remove the cylinder head and gasket. Discard
the gasket.
CAUTION: Do not lay the cylinder head on its gas-
ket sealing surface, do to the design of the cylinder
head gasket any distortion to the cylinder head
sealing surface may prevent the gasket from prop-
erly sealing resulting in leaks.
INSTALLATION
NOTE: The cylinder head bolts are tightened using
a torque plus angle procedure. The bolts must be
examined BEFORE reuse. If the threads are necked
down the bolts should be replaced.
Necking can be checked by holding a straight edge
against the threads (Fig. 24). If all the threads do not
contact the scale, the bolt should be replaced.
9 - 32 ENGINE - 3.7LDR
CYLINDER HEAD - RIGHT (Continued)

CAUTION: When cleaning cylinder head and cylin-
der block surfaces, DO NOT use a metal scraper
because the surfaces could be cut or ground. Use
only a wooden or plastic scraper.
(1) Clean the cylinder head and cylinder block
mating surfaces (Fig. 25).
(2) Position the new cylinder head gasket on the
locating dowels.
CAUTION: When installing cylinder head, use care
not damage the tensioner arm or the guide arm.(3) Position the cylinder head onto the cylinder
block. Make sure the cylinder head seats fully over
the locating dowels.
NOTE: The four M8 cylinder head mounting bolts
require sealant to be added to them before install-
ing. Failure to do so may cause leaks.
(4) Lubricate the cylinder head bolt threads with
clean engine oil and install the eight M10 bolts.
(5) Coat the four M8 cylinder head bolts with
Mopar Lock and Seal Adhesivethen install the
bolts.
NOTE: The cylinder head bolts are tightened using
an angle torque procedure, however, the bolts are
not a torque-to-yield design.
(6) Tighten the bolts in sequence using the follow-
ing steps and torque values:
²Step 1: Tighten bolts 1±8, 27 N´m (20 ft. lbs.).
²Step 2: Verify that bolts 1±8, all reached 27 N´m
(20 ft. lbs.), by repeating step-1 without loosening the
bolts. Tighten bolts 9 thru 12 to 14 N´m (10 ft. lbs.).
²Step 3: Tighten bolts 1±8, 90 degrees (Fig. 26).
²Step 4: Tighten bolts 1±8, 90 degrees, again.
Tighten bolts 9±12, 26 N´m (19 ft. lbs.)
CAUTION: The nut on the right side camshaft
sprocket should not be removed for any reason, as
the sprocket and camshaft sensor target wheel is
serviced as an assembly. If the nut was removed
retorque nut to 5 ft. lbs.( 60 in. lbs.).
Fig. 24 Checking Cylinder Head Bolts for Stretching
(Necking)
1 - STRETCHED BOLT
2 - THREADS ARE NOT STRAIGHT ON LINE
3 - THREADS ARE STRAIGHT ON LINE
4 - UNSTRETCHED BOLT
Fig. 25 Proper Tool Usage For Surface Preparation
1 - PLASTIC/WOOD SCRAPER
Fig. 26 Cylinder Head Tightening Sequence
* - INDICATES SEALANT ON THREADS
DRENGINE - 3.7L 9 - 33
CYLINDER HEAD - RIGHT (Continued)

(7) Position the secondary chain onto the camshaft
drive gear, making sure one marked chain link is on
either side of the V6 mark on the gear then using
Special Tool 8428 Camshaft Wrench, position the
gear onto the camshaft.
CAUTION: Remove excess oil from camshaft
sprocket retaining bolt before reinstalling bolt. Fail-
ure to do so may cause over-torquing of bolt result-
ing in bolt failure.
(8) Install the camshaft drive gear retaining bolt.
(9) Install the right side secondary chain guide(Re-
fer to 9 - ENGINE/VALVE TIMING/TIMING BELT/
CHAIN AND SPROCKETS - INSTALLATION).
(10) Install the cylinder head access plug.
(11) Re-set and install the right side secondary
chain tensioner(Refer to 9 - ENGINE/VALVE TIM-
ING/TIMING BELT/CHAIN AND SPROCKETS -
INSTALLATION).
(12) Remove Special Tool 8429.
(13) Install the timing chain cover(Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(14) Install the crankshaft damper(Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
INSTALLATION). Tighten damper bolt 175 N´m (130
Ft. Lbs.).
(15) Install accessory drive belt(Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).
(16) Install the fan shroud(Refer to 7 - COOLING/
ENGINE/RADIATOR FAN - INSTALLATION).
(17) Install the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - INSTALLATION).
(18) Install the intake manifold(Refer to 9 -
ENGINE/MANIFOLDS/INTAKE MANIFOLD -
INSTALLATION).
(19) Install oil fill housing onto cylinder head.
(20) Refill the cooling system(Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(21) Raise the vehicle.
(22) Install the exhaust pipe onto the right
exhaust manifold.
(23) Lower the vehicle.
(24) Reconnect battery negative cable.
(25) Start the engine and check for leaks.
CAMSHAFT(S)
DESCRIPTION
The camshafts consist of powdered metal steel
lobes which are sinter-bonded to a steel tube. Four
bearing journals are machined into the camshaft.
Camshaft end play is controlled by two thrust wallsthat border the nose piece journal. Engine oil enters
the hollow camshafts at the third journal and lubri-
cates every intake lobe rocker through a drilled pas-
sage in the intake lobe.
REMOVAL
CAUTION: When the timing chain is removed and
the cylinder heads are still installed, DO NOT force-
fully rotate the camshafts or crankshaft indepen-
dently of each other. Severe valve and/or piston
damage can occur.
CAUTION: When removing the cam sprocket, timing
chains or camshaft, Failure to use special tool 8379
will result in hydraulic tensioner ratchet over exten-
sion, Requiring timing chain cover removal to re-set
the tensioner ratchet.
(1) Remove the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(2) Set engine to TDC cylinder #1, camshaft
sprocket V6 marks at the 12 o'clock position.
(3) Mark one link on the secondary timing chain
on both sides of the V6 mark on the camshaft
sprocket to aid in installation.
CAUTION: Do not hold or pry on the camshaft tar-
get wheel for any reason, Severe damage will occur
to the target wheel. A damaged target wheel could
cause a vehicle no start condition.
(4) Loosen butDO NOTremove the camshaft
sprocket retaining bolt. Leave bolt snug against
sprocket.
NOTE: The timing chain tensioners must be
secured prior to removing the camshaft sprockets.
Failure to secure tensioners will allow the tension-
ers to extend, requiring timing chain cover removal
in order to reset tensioners.
CAUTION: Do not force wedge past the narrowest
point between the chain strands. Damage to the
tensioners may occur.
(5) Position Special Tool 8379 timing chain wedge
between the timing chain strands. Tap the tool to
securely wedge the timing chain against the ten-
sioner arm and guide.
(6) Remove the camshaft position sensor.
(7) Hold the camshaft with Special Tool 8428 Cam-
shaft Wrench, while removing the camshaft sprocket
bolt and sprocket.
9 - 34 ENGINE - 3.7LDR
CYLINDER HEAD - RIGHT (Continued)

(4) Determine taper by subtracting the smaller
diameter from the larger diameter.
(5) Rotate measuring device 90É and repeat steps
above.
(6) Determine out-of-roundness by comparing the
difference between each measurement.
(7) If cylinder bore taper does not exceed 0.025
mm (0.001 inch) and out-of-roundness does not
exceed 0.025 mm (0.001 inch), the cylinder bore can
be honed. If the cylinder bore taper or out- of-round
condition exceeds these maximum limits, the cylinder
block must be replaced. A slight amount of taper
always exists in the cylinder bore after the engine
has been in use for a period of time.
CRANKSHAFT
DESCRIPTION
The crankshaft is constructed of nodular cast iron.
The crankshaft is a three throw split pin design with
six counterweights for balancing purposes. The
crankshaft is supported by four select fit main bear-
ings with the number two serving as the thrust
washer location. The main journals of the crankshaft
are cross drilled to improve rod bearing lubrication.
The number six counterweight has provisions for
crankshaft position sensor target wheel mounting.
The select fit main bearing markings are located on
the rear side of the target wheel (Fig. 31). The crank-
shaft oil seals are one piece design. The front oil seal
is retained in the timing chain cover, and the rear
seal is pressed in to a bore formed by the cylinder
block and the bedplate assembly.
REMOVAL
NOTE: To remove the crankshaft from the engine,
the engine must be removed from the vehicle.
(1) Remove the engine(Refer to 9 - ENGINE -
REMOVAL).
(2) Remove the engine oil pump(Refer to 9 -
ENGINE/LUBRICATION/OIL PUMP - REMOVAL).
CAUTION: DO NOT pry on the oil pan gasket when
removing the oil pan, The oil pan gasket is mounted
to the cylinder block in three locations and will
remain attached to block when removing oil pan.
Gasket can not be removed with oil pan.
(3) Remove the bedplate mounting bolts. Note the
location of the two stud bolts for installation.
(4) Remove the connecting rods from the crank-
shaft.CAUTION: The bedplate to cylinder block mating
surface is a critical sealing surface. Do not pry on
or damage this surface in anyway.
NOTE: The bedplate contains the lower main bear-
ing halves. Use care when handling bedplate as not
to drop or damage bearing halves. Installing main
bearing halves in the wrong position will cause
severe damage to the crankshaft.
NOTE: The bedplate has pry points cast into it. Use
these points only. The pry points are shown below.
(5) Carefully pry on the pry points (Fig. 32) to
loosen the bedplate then remove the bedplate.
CAUTION: When removing the crankshaft, use care
not to damage bearing surfaces on the crankshaft.
(6) Remove the crankshaft.
(7) Remove the crankshaft tone wheel.
Fig. 31 CRANKSHAFT AND TARGET RING
1 - CRANKSHAFT
2 - CRANKSHAFT POSITION SENSOR TARGET RING
DRENGINE - 3.7L 9 - 39
ENGINE BLOCK (Continued)

INSTALLATION
CAUTION: Main bearings are select fit. Refer to
Crankshaft Main Bearings in this section for proper
bearing selections.
CAUTION: When installing crankshaft, use care not
to damage bearing surfaces on the crankshaft.
NOTE: Apply sealant to the tone wheel retaining
screws prior to installation.
(1) Lubricate upper main bearing halves with
clean engine oil.
(2) Install the crankshaft tone wheel. Torque the
mounting screws to 15 N´m (11 ft. lbs.).
(3) Position crankshaft in cylinder block.
(4) Install the thrust washers (Fig. 33).
CAUTION: The bedplate to cylinder block mating
surface must be coated with MoparTEngine RTV
sealant prior to installation. Failure to do so will
cause severe oil leaks.NOTE: Make sure that the bedplate and cylinder
block sealing surfaces are clean and free of oil or
other contaminants. Contaminants on the sealing
surfaces may cause main bearing distortion and/or
oil leaks.
(5) Apply a 2.5mm (0.100 inch) bead of Mopart
Engine RTV sealant to the cylinder block-to-bedplate
mating surface as shown (Fig. 34).
(6) Coat the crankshaft main bearing journals
with clean engine oil and position the bedplate onto
the cylinder block.
NOTE: Lubricate the bedplate retaining bolts with
clean engine oil prior to installation.
Fig. 33 Crankshaft Thrust Washer Installation
1 - CRANKSHAFT THRUST WASHER
Fig. 34 BEDPLATE SEALANT
1 - CYLINDER BLOCK
2 - SEALENT
3 - SEALANT
DRENGINE - 3.7L 9 - 41
CRANKSHAFT (Continued)

CRANKSHAFT MAIN
BEARINGS
STANDARD PROCEDURE
MAIN BEARING FITTING
SELECT FIT IDENTIFICATION
The main bearings are ªselect fitº to achieve proper
oil clearances. For main bearing selection, the crank-
shaft position sensor target wheel has grade identifi-
cation marks stamped into it (Fig. 36). These marks
are read from left to right, corresponding with jour-
nal number 1, 2, 3, 4. The crankshaft position sensor
target wheel is mounted to the number 6 counter
weight on the crankshaft.
INSPECTION
Wipe the inserts clean and inspect for abnormal
wear patterns and for metal or other foreign material
imbedded in the lining. Normal main bearing insert
wear patterns are illustrated.
Inspect the back of the inserts for fractures, scrap-
ings or irregular wear patterns.
Inspect the upper insert locking tabs for damage.
Replace all damaged or worn bearing inserts.
MAIN BEARING JOURNAL DIAMETER
(CRANKSHAFT REMOVED)
Remove the crankshaft from the cylinder block(Re-
fer to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT
- REMOVAL).
Clean the oil off the main bearing journal.
Determine the maximum diameter of the journal
with a micrometer. Measure at two locations 90É
apart at each end of the journal.
The maximum allowable taper is 0.008mm (0.0004
inch.) and maximum out of round is 0.005mm (0.002
inch). Compare the measured diameter with the jour-
nal diameter specification (Main Bearing Fitting
Chart). Select inserts required to obtain the specified
bearing-to-journal clearance.
Install the crankshaft into the cylinder block(Refer
to 9 - ENGINE/ENGINE BLOCK/CRANKSHAFT -
INSPECTION).
Check crankshaft end play.
CRANKSHAFT MAIN BEARING SELECTION
(1) Service main bearings are available in four
grades. The chart below identifies the four service
grades available.
Crankshaft JOURNAL SIZE
SIZE mm (in.)
MARKING
9R9Size 63.488 - 63.496 mm
(2.4995 - 2.4998 in.)
9S9Size 63.496 - 63.500 mm (2.4998 - 2.4999
in.)
9T9Size 63.500 - 63.504 mm (2.4999 - 2.501
in.)
9U9Size 63.504 - 63.512 mm (2.5001 - 2.5004
in.)
Bearing size
Bearing
CodeSize Application
Upper Bearing
A.2.443 - 2.447
mmUse with crankshaft
size9R9
(.0961 - .0963
in.)
B2.439 - 2.443
mmUse with crankshaft
9S, T9
(0.960 -.o961
in.)
C2.435 - 2.439
mmUse with crankshaft
9U9
Fig. 36 MARKINGS ON TARGET WHEEL
1 - REARMOST CRANKSHAFT COUNTER WEIGHT
2 - TARGET WHEEL
3 - MAIN BEARING SELECT FIT MARKINGS
DRENGINE - 3.7L 9 - 43