
LUBRICATION
DESCRIPTION
NOTE: Refer to (Fig. 148) and (Fig. 149) for circuit
illustrations.
A gear driven gerotor type oil pump is mounted
behind the front gear cover in the lower right portion
on the engine.
OPERATION
A gerotor style oil pump draws oil from the crank-
case through the suction tube and delivers it through
the block where it enters the oil cooler cover and
pressure regulator valve. When oil pressure exceeds
449 kPa (65 PSI), the valve opens exposing the dump
port, which routes excess oil back to the oil sump.
At the same time, oil is directed to a cast in pas-
sage in the oil cooler cover, leading to the oil cooler
element. As the oil travels through the element
plates, it is cooled by engine coolant traveling past
the outside of the plates. It is then routed to the oil
filter head and through a full flow oil filter. If a
plugged filter is encountered, the filter by-pass valve
opens, allowing unfiltered oil to lubricate the engine.
This condition can be avoided by frequent oil and fil-
ter changes, per the maintenance schedules found in
the owners manual. The by-pass valve is calibrated
to open when it sees a pressure drop of more than
344 kPa (50 psi) across the oil filter.The oil filter head then divides the oil between the
engine and the turbocharger. The turbocharger
receives filtered, cooled and pressurized oil through a
supply line from the filter head. The oil lubricates
the turbocharger and returns to the pan by way of a
drain tube connecting the bottom of the turbocharger
to a pressed in tube in the cylinder block.
Oil is then carried across the block to an angle
drilling which intersects the main oil rifle. The main
oil rifle runs the length of the block and delivers oil
to the crankshaft main journals and valve train. Oil
travels to the crankshaft through a series of transfer
drillings (one for each main bearing) and lubricates a
groove in the main bearing upper shell. From there
another drilling feeds the camshaft main journals.
The piston cooling nozzles are also supplied by the
main bearing upper shell. Crankshaft internal cross-
drillings supply oil to the connecting rod journals.
Another series of transfer drillings intersecting the
main oil rifle supply the valve train components. Oil
travels up the drilling, through a hole in the head
gasket, and through a drilling in the cylinder head
(one per cylinder), where it enters the rocker arm
pedestal and is divided between the intake and
exhaust rocker arm. Oil travels up and around the
rocker arm mounting bolt, and lubricates the rocker
shaft by cross drillings that intersect the mounting
bolt hole. Grooves at both ends of the rocker shaft
supply oil through the rocker arm where the oil trav-
els to the push rod and socket balls (Fig. 148) and
(Fig. 149).
9 - 292 ENGINE 5.9L DIESELBR/BE

²Milky discoloration indicates coolant dilution.
(4) Clean the area around the oil filter head.
Remove the filter (Refer to 9 - ENGINE/LUBRICA-
TION/OIL FILTER - REMOVAL).
(5) Install new oil filter (Refer to 9 - ENGINE/LU-
BRICATION/OIL FILTER - INSTALLATION).
(6) Clean the drain plug and the sealing surface of
the pan. Check the condition of the threads and seal-
ing surface on the oil pan and drain plug.
(7) Install the drain plug. Tighten the plug to 60
N´m (44 ft. lbs.) torque.
(8) Use only High-Quality Multi-Viscosity lubricat-
ing oil in the Cummins Turbo Diesel engine. Choose
the correct oil for the operating conditions (Refer to
LUBRICATION & MAINTENANCE/FLUID TYPES -
DESCRIPTION).
(9) Fill the engine with the correct grade of new oil
(Refer to LUBRICATION & MAINTENANCE/FLUID
CAPACITIES - SPECIFICATIONS).
(10) Start the engine and operate it at idle for sev-
eral minutes. Check for leaks at the filter and drain
plug.
(11) Stop engine. Wait several minutes to allow the
oil to drain back to the pan and check the level
again.
USED ENGINE OIL DISPOSAL Care should be
exercised when disposing of used engine oil after
it has been drained from a vehicle's engine.
OIL COOLER & LINES
CLEANING AND INSPECTION
Clean the sealing surfaces.
Apply 483 kPa (70 psi) air pressure to the element
to check for leaks. If the element leaks, replace the
element.
OIL FILTER
REMOVAL
(1) Clean the area around the oil filter head.
Remove the filter using a 90-95 mm filter wrench.
(2) Clean the gasket surface of the filter head. The
filter canister O-Ring seal can stick on the filter
head. Make sure it is removed.
INSTALLATION
(1) Fill the oil filter element with clean oil before
installation. Use the same type oil that will be used
in the engine.
(2) Apply a light film of lubricating oil to the seal-
ing surface before installing the filter.CAUTION: Mechanical over-tightening may distort
the threads or damage the filter element seal.
(3) Install the filter until it contacts the sealing
surface of the oil filter adapter. Tighten filter an
additional ó turn.
OIL PAN
REMOVAL
(1) Disconnect the battery negative cables.
(2) Raise vehicle on hoist.
(3) Remove transmission and transfer case (if
equipped).
(4) Remove flywheel.
(5) Disconnect starter cables from starter motor.
(6) Remove starter motor (Refer to 8 - ELECTRI-
CAL/STARTING/STARTER MOTOR - REMOVAL)
and transmission adapter plate assembly.
WARNING: HOT OIL CAN CAUSE PERSONAL
INJURY.
(7) Drain the engine oil (Refer to 9 - ENGINE/LU-
BRICATION/OIL - STANDARD PROCEDURE).
(8) Install the oil pan drain plug with a new seal-
ing washer and tighten to 60 N´m (44 ft. lbs.) torque.
(9) Remove oil pan bolts, break the pan to block
seal, and lower pan slightly and remove oil suction
tube fasteners.
(10) Remove oil pan and suction tube (Fig. 151).
Fig. 151 Oil Pan, Suction Tube and Gasket
1 - GASKET
2 - SUCTION TUBE
3 - OIL PAN
9 - 296 ENGINE 5.9L DIESELBR/BE
OIL (Continued)

(10) Remove the exhaust manifold-to-cylinder head
bolts and spacers (Fig. 173).
(11) Remove the exhaust manifold and gaskets
(Fig. 173).
CLEANING
Clean the cylinder head and exhaust manifold seal-
ing surfaces with a suitable scraper. Use a Scotch-
BriteŸ pad or equivalent.
INSPECTION
Inspect the exhaust manifold for cracks. Measure
the exhaust manifold for flatness. Place a ruler over
all of the exhaust ports and insert a feeler gauge
between the port flange and the ruler.
INSTALLATION
(1) Using new gaskets, install the exhaust mani-
fold and gaskets. Install the bolts and spacers and
tighten the bolts in the sequence shown in (Fig. 173)
to 43 N´m (32 ft. lbs.) torque.
(2) Install the cab heater return hose to the man-
ifold bolt stud. Tighten the nut to 24 N´m (18 ft. lbs.)
torque.
(3) Install the turbocharger. Apply anti-seize to the
studs and then tighten the turbocharger mounting
nuts to 32 N´m (24 ft. lbs.) torque.(4) Install the oil drain tube and oil supply line to
the turbocharger. Tighten the drain tube bolts to 24
N´m (18 ft. lbs.) torque.
(5)Pre-lube the turbocharger.Pour 50 to 60 cc
(2 to 3 oz.) clean engine oil in the oil supply line fit-
ting. Rotate the turbocharger impeller by hand to
distrubute the oil thoroughly.
(6) Install and tighten the oil supply line fitting
nut to 20 N´m (133 in. lbs.) torque.
(7) Position the charge air cooler inlet pipe to the
turbocharger. With the clamp in position, tighten the
clamp nut to 8 N´m (72 in. lbs.) torque.
(8) Position the air inlet hose to the turbocharger
(Fig. 171). Tighten the clamp to 8 N´m (72 in. lbs.)
torque.
(9) Raise vehicle on hoist.
(10) Connect the exhaust pipe to the turbocharger
(Fig. 170) and tighten the bolts to 34 N´m (25 ft. lbs.)
torque.
(11) Lower the vehicle.
(12) Connect the battery negative cables.
(13) Start the engine to check for leaks.
GEAR HOUSING
REMOVAL
(1) Disconnect the battery negative cables.
(2) Raise vehicle on hoist.
(3) Remove the oil pan and suction tube (Refer to 9
- ENGINE/LUBRICATION/OIL PAN - REMOVAL).
(4) Partially drain engine coolant into container
suitable for re-use (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(5) Lower vehicle.
(6) Remove radiator upper hose.
(7) Disconnect coolant recovery bottle hose from
radiator filler neck and lift bottle off of fan shroud.
(8) Disconnect windshield washer pump supply
hose and electrical connections and lift washer bottle
off of fan shroud.
(9) Remove the fan shroud-to-radiator mounting
bolts.
(10) Remove viscous fan/drive assembly (Refer to 7
- COOLING/ENGINE/RADIATOR FAN - REMOVAL).
(11) Remove the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(12) Remove the cooling fan support/hub from the
front of the engine (Fig. 174).
(13) Raise the vehicle on hoist.
(14) Remove the crankshaft damper (Fig. 175)
(Refer to 9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - REMOVAL).
(15) Lower the vehicle.
Fig. 173 Exhaust Manifold and Gaskets
9 - 304 ENGINE 5.9L DIESELBR/BE
EXHAUST MANIFOLD (Continued)

(3) Install the injection pump (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL INJECTION
PUMP - INSTALLATION).
(4) Install the camshaft (Refer to 9 - ENGINE/EN-
GINE BLOCK/CAMSHAFT & BEARINGS (IN
BLOCK) - INSTALLATION). Align the crankshaft,
camshaft, and injection pump gear marks as shown
in (Fig. 178).
(5) If a new housing is installed, the camshaft
position sensor must be transferred to the new hous-
ing.
(6) Obtain a seal pilot/installation tool from a
crankshaft front seal service kit and install the pilot
into the crankshaft front oil seal.
(7) Apply a bead of MopartSilicone Rubber Adhe-
sive Sealant or equivalent to the gear housing cover.
Be sure to surround all through holes.
(8) Using the seal pilot to align the cover (Fig.
179), install the cover to the housing and install the
bolts. Tighten the bolts to 24 N´m (18 ft. lbs.) torque.
(9) Remove the seal pilot.
(10) Raise the vehicle.
(11) Trim any excess gear housing gasket to make
it flush with the oil pan rail.
(12) Using a new gasket, install the oil pan and
suction tube (Refer to 9 - ENGINE/LUBRICATION/
OIL PAN - INSTALLATION).
(13) Install the crankshaft damper (Fig. 175)
(Refer to 9 - ENGINE/ENGINE BLOCK/VIBRATION
DAMPER - INSTALLATION).
(14) Lower vehicle.
(15) Install the fan support/hub assembly (Fig.
174) and tighten bolts to 24 N´m (18 ft. lbs.) torque.(16) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(17) Install the cooling fan and shroud together
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
(18) Install the windshield washer reservoir to the
fan shroud and connect the washer pump supply
hose and electrical connection.
(19) Install the coolant recovery bottle to the fan
shroud and connect the hose to the radiator filler
neck.
(20) Install the radiator upper hose and clamps.
(21) Add engine oil.
(22) Add coolant (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(23) Connect the battery cables.
(24) Start engine and inspect for leaks.
GEAR HOUSING COVER
REMOVAL
(1) Disconnect both battery negative cables.
(2) Raise vehicle on hoist.
(3) Partially drain engine coolant into container
suitable for re-use (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(4) Lower vehicle.
(5) Remove radiator upper hose.
(6) Disconnect coolant recovery bottle hose from
radiator filler neck and lift bottle off of fan shroud.
(7) Disconnect windshield washer pump supply
hose and electrical connections and lift washer bottle
off of fan shroud.
(8) Remove viscous fan/drive assembly (Refer to 7 -
COOLING/ENGINE/RADIATOR FAN - REMOVAL).
Fig. 178 Camshaft/Crankshaft Gear Alignment
Fig. 179 Installing Cover with Seal Pilot
1 - SEAL PILOT
9 - 306 ENGINE 5.9L DIESELBR/BE
GEAR HOUSING (Continued)

(8) Install the fan support/hub assy. (Fig. 180) and
tighten bolts to 24 N´m (18 ft. lbs.) torque.
(9) Install the accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
INSTALLATION).
(10) Install the cooling fan and shroud together
(Refer to 7 - COOLING/ENGINE/RADIATOR FAN -
INSTALLATION).
(11) Install the windshield washer reservoir to the
fan shroud and connect the washer pump supply
hose and electrical connection.(12) Install the coolant recovery bottle to the fan
shroud and connect the hose to the radiator filler
neck.
(13) Install the radiator upper hose and clamps.
(14) Add coolant (Refer to 7 - COOLING - STAN-
DARD PROCEDURE).
(15) Connect the battery cables.
(16) Start engine and inspect for leaks.
9 - 308 ENGINE 5.9L DIESELBR/BE
GEAR HOUSING COVER (Continued)

(11) Inspect accelerator cable, transmission throt-
tle cable (if equipped) and cruise control cable con-
nections (if equipped). Check their connections to the
throttle arm of throttle body for any binding or
restrictions.
(12) If equipped with vacuum brake booster, verify
that vacuum booster hose is firmly connected to fit-
ting on intake manifold. Also check connection to
brake vacuum booster.
(13) Inspect the air cleaner inlet and air cleaner
element for dirt or restrictions.
(14) Inspect radiator grille area, radiator fins and
air conditioning condenser for restrictions.
(15) Verify that the intake manifold air tempera-
ture sensor wire connector is firmly connected to har-
ness connector (Fig. 5).
(16) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 6). Also verify
that rubber L-shaped fitting from MAP sensor to the
throttle body is firmly connected (Fig. 7).
(17) Verify that fuel injector wire harness connec-
tors are firmly connected to injectors in the correct
order. Each harness connector is numerically tagged
with the injector number (INJ 1, INJ 2 etc.) of its
corresponding fuel injector and cylinder number.
(18) Verify harness connectors are firmly con-
nected to idle air control (IAC) motor, throttle posi-
tion sensor (TPS) and manifold absolute pressure
(MAP) sensor (Fig. 6).
(19) Verify that wire harness connector is firmly
connected to the engine coolant temperature sensor
(Fig. 8).
(20) Raise and support the vehicle.(21) Verify oxygen sensor wire connectors are
firmly connected to the sensors. Inspect sensors and
connectors for damage (Fig. 9), (Fig. 10) or (Fig. 11).
(22) Inspect for pinched or leaking fuel tubes.
Inspect for pinched, cracked or leaking fuel hoses.
Fig. 5 Air Temperature
1 - INTAKE MANIFOLD AIR TEMPERATURE SENSOR
2 - ELECTRICAL CONNECTOR
Fig. 6 Sensor and IAC Motor LocationÐTypical (V-8
Shown)
1 - MAP SENSOR
2 - IDLE AIR CONTROL MOTOR
3 - THROTTLE POSITION SENSOR
Fig. 7 Rubber L-Shaped FittingÐMAP Sensor-to-
Throttle BodyÐ3.9L/5.2L/5.9L Engines
1 - MAP SENSOR
2 - RUBBER FITTING
3 - IDLE AIR PASSAGE
14 - 30 FUEL INJECTION - GASOLINEBR/BE
FUEL INJECTION - GASOLINE (Continued)

(23) Inspect for exhaust system restrictions such
as pinched exhaust pipes, collapsed muffler or
plugged catalytic convertor.
(24) If equipped with automatic transmission, ver-
ify that electrical harness is firmly connected to park/
neutral switch. Refer to 21, Automatic Transmission.
(25) Verify electrical harness is firmly connected to
rear wheel speed sensor. Verify rear wheel speed sen-sor is firmly attached to rear axle with proper air
gap. Refer to 5, Brakes for information.
(26) If equipped with 4±wheel antilock brake sys-
tem, verify electrical harness is firmly connected to
each front wheel speed sensor. Verify both front
wheel speed sensors are firmly attached. Refer to 5,
Brakes for information.
(27) Verify that fuel pump/gauge sender unit wire
connector is firmly connected to harness connector.
(28) Inspect fuel hoses at fuel pump/gauge sender
unit for cracks or leaks.
(29) Inspect transmission torque convertor housing
(automatic transmission) or clutch housing (manual
transmission) for damage to timing ring on drive
plate/flywheel.
(30) Verify that battery cable and solenoid feed
wire connections to the starter solenoid are tight and
clean. Inspect for chaffed wires or wires rubbing up
against other components.
Fig. 8 Engine Coolant Temperature
1 - GENERATOR
2 - A/C COMPRESSOR
3 - ENGINE COOLANT TEMPERATURE SENSOR
4 - ELEC. CONN.
Fig. 9 Left/Right Oxygen SensorsÐHDC Engines
1 - DUAL OXYGEN SENSORS
2 - TOP OF TRANSMISSION
Fig. 10 Pre-Catalyst/Post-Catalyst Sensors
1 - POST CATALYST OXYGEN SENSOR (1/3)
2 - PRE-CATALYST OXYGEN SENSOR (1/2)
Fig. 11 Oxygen Sensors
BR/BEFUEL INJECTION - GASOLINE 14 - 31
FUEL INJECTION - GASOLINE (Continued)

(12) If equipped with vacuum brake booster, verify
that vacuum booster hose is firmly connected to fit-
ting on intake manifold. Also check connection to
brake vacuum booster.
(13) Inspect the air cleaner inlet and air cleaner
element for dirt or restrictions.
(14) Inspect radiator grille area, radiator fins and
air conditioning condenser for restrictions.
(15) Verify that the intake manifold air tempera-
ture sensor wire connector is firmly connected to har-
ness connector (Fig. 15).
(16) Verify that MAP sensor electrical connector is
firmly connected to MAP sensor (Fig. 16).(17) Verify that fuel injector wire harness connec-
tors are firmly connected to injectors in the correct
order. Each harness connector is numerically tagged
with the injector number (INJ 1, INJ 2 etc.) of its
corresponding fuel injector and cylinder number.
(18) Verify harness connectors are firmly con-
nected to idle air control (IAC) motor and throttle
position sensor (TPS).
(19) Verify that wire harness connector is firmly
connected to the engine coolant temperature sensor
(Fig. 17).
(20) Raise and support the vehicle.
(21) Verify that all oxygen sensor wire connectors
are firmly connected to the sensors. Inspect sensors
and connectors for damage (Fig. 18), (Fig. 19) or (Fig.
20).
(22) Inspect for pinched or leaking fuel tubes.
Inspect for pinched, cracked or leaking fuel hoses.
(23) Inspect for exhaust system restrictions such
as pinched exhaust pipes, collapsed muffler or
plugged catalytic convertor.
(24) If equipped with automatic transmission, ver-
ify that electrical harness is firmly connected to park/
neutral switch. Refer to 21, Automatic Transmission.
Fig. 15 Air Temperature SensorÐ8.0L Engine
1 - INTAKE MANIFOLD AIR TEMP. SENSOR
2 - INTAKE MANIFOLD
Fig. 16 Map Sensor Ð8.0L Engine
1 - MAP SENSOR
2 - MOUNTING BOLTS
3 - THROTTLE BODY
Fig. 17 Engine Coolant Temperature SensorÐ8.0L
Engine
1 - ENGINE COOLANT TEMP. SENSOR
2 - THERMOSTAT HOUSING
3 - GENERATOR
BR/BEFUEL INJECTION - GASOLINE 14 - 33
FUEL INJECTION - GASOLINE (Continued)