1998 DODGE RAM 1500 one

ENGINE 5.9L DIESEL
DESCRIPTION
The cylinder block is constructed of cast iron. The
casting is a skirted design which incorporates longi-
tudal ribs for superior strength and noise reduction.
The block incorporates metric straight thread o-ring
fittings at lubrication oil access points. The engine
(Fig. 1) is manufactured with the cylinders being a
non-sleeved type cylinder. However, one approved
service method is to bore out the cylinders and add
cylinder sleeves to the cylinder block.
The cylinders are numbered front to rear (Fig. 2); 1
to 6. The firing order is 1±5±3±6±2±4.
Fig. 1 CumminsT24-Valve Turbo-Diesel Engine
Fig. 2 Cylinder Numbering
9 - 232 ENGINE 5.9L DIESELDR

CONDITION POSSIBLE CAUSES CORRECTION
2. Engine running too cold. 2. Refer to Coolant Temperature Below
Normal (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
3. Oil viscosity too thick. 3. Make sure the correct oil is being used.
(Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
4. Oil pressure relief valve stuck
closed or binding4. Check and replace valve.
LUBRICATING OIL LOSS 1. External leaks. 1. Visually inspect for oil leaks. Repair as
required.
2. Crankcase being overfilled. 2. Verify that the correct dipstick is being
used.
3. Incorrect oil specification or
viscosity.3. (a) Make sure the correct oil is being
used (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
(b) Look for reduced viscosity from dilution
with fuel.
(c) Review/reduce oil change intervals.
4. Oil cooler leak 4. Check and replace the oil cooler.
5. High blow-by forcing oil out the
breather.5. Check the breather tube area for signs of
oil loss. Perform the required repairs.
6. Turbocharger leaking oil to the air
intake.6. Inspect the air ducts for evidence of oil
transfer. Repair as required.
COMPRESSION KNOCKS 1. Air in the fuel system. 1. Identify location of air leak and repair. Do
not bleed high pressure fuel system.
2. Poor quality fuel or water/gasoline
contaminated fuel.2. Verify by operating from a temporary
tank with good fuel. Clean and flush the
fuel tank. Replace fuel/water separator filter.
3. Engine overloaded. 3. Verify the engine load rating is not being
exceeded.
4. Improperly operating injectors. 5. Check and replace misfiring/inoperative
injectors.
EXCESSIVE VIBRATION 1. Loose or broken engine mounts. 1. Replace engine mounts.
2. Damaged fan or improperly
operating accessories.2. Check and replace the vibrating
components.
3. Improperly operating vibration
damper3. Inspect/replace vibration damper.
4. Improperly operating electronically
controlled viscous fan drive.4. Inspect/replace fan drive.
5. Worn or damaged generator
bearing.5. Check/replace generator.
6. Flywheel housing misaligned. 6. Check/correct flywheel alignment.
9 - 234 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
7. Loose or broken power
component.7. Inspect the crankshaft and rods for
damage that causes an unbalance
condition. Repair/replace as required.
8. Worn or unbalanced driveline
components.8. Check/repair driveline components.
EXCESSIVE ENGINE
NOISES1. Drive belt squeal, insufficient
tension or abnormally high loading.1. Check the automatic tensioner and
inspect the drive belt. Make sure water
pump, tensioner pulley, fan hub, generator
and power steering pump turn freely.
2. Intake air or exhaust leaks. 2. Refer to Excessive Exhaust Smoke
(Refer to 9 - ENGINE - DIAGNOSIS AND
TESTING).
3. Excessive valve lash. 3. Adjust valves. Make sure the push rods
are not bent and rocker arms, adjusting
screws, crossheads, are not severely worn.
Replace bent or severely worn components.
4. Turbocharger noise. 4. Check turbocharger impeller and turbine
wheel for housing contact. Repair/replace
as required.
5. Gear train noise. 5. Visually inspect and measure gear
backlash. Replace gears as required.
6. Power function knock. 6. Check/replace rod and main bearings.
DRENGINE 5.9L DIESEL 9 - 235
ENGINE 5.9L DIESEL (Continued)

DIAGNOSIS AND TESTING - CYLINDER
COMPRESSION/LEAKAGE TESTS
CYLINDER COMPRESSION PRESSURE
The results of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
Ensure batteries are completely charged and the
engine starter motor is in good operating condition.
Otherwise, the indicated compression pressures may
not be valid for diagnostic purposes.
(1) Disconnect the fuel inlet line to the fuel trans-
fer pump. Plug the fuel line from the fuel tank.
(2) Start the engine and idle until the engine stalls
(runs out of fuel).
(3) Disconnect all three injector wire harness con-
nectors at the rocker housing.
(4) Remove the breather cover and cylinder head
cover.
(5) Remove the high pressure fuel line between the
cylinder head and fuel rail for the cylinder to be
tested. Use tool# 9011 to cap this fuel rail on the cyl-
inder being tested.
(6) Remove the exhaust rocker lever.
(7) Use Tool 9010 to remove the injector and cop-
per sealing washer.
(8) Install the exhaust rocker lever and torque to
36 N´m (27 ft. lbs.).
(9) Cover the remaining rocker levers with clean
shop towels to prevent any oil splatter under the
hood.
(10) Place a rag over the compression test tool fit-
ting. Crank the engine for 2±3 seconds to purge any
fuel that may have drained into the cylinder when
the injector was removed.
(11) Connect the compression test gauge.
(12) Crank the engine for 5 seconds and record the
pressure reading. Repeat this step three times and
calculate the average of the three readings.
NOTE: The minimum cylinder pressure is 350 psi.
Cylinder pressure should be within 20% from cylin-
der to cylinder.
(13) Combustion pressure leakage can be checked
if cylinder pressure is below the specification. Per-
form the leakage test procedure on each cylinder
according to the tester manufacturer instructions.
(14) Upon completion of the test check an erase
any engine related fault codes.
CYLINDER COMBUSTION PRESSURE LEAKAGE
The combustion pressure leakage test provides an
accurate means for determining engine condition.
Combustion pressure leakage testing will detect:²Exhaust and intake valve leaks (improper seat-
ing).
²Leaks between adjacent cylinders or into water
jacket.
²Any causes for combustion/compression pressure
loss
(1) Start and operate the engine until it attains
normal operating temperature.
(2) Remove the breather cover and cylinder head
cover.
(3) Disconnect all three injector wire harness con-
nectors at the rocker housing.
(4) Bring the cylinder to be tested to TDC.
(5) Remove the high pressure fuel line between the
cylinder head and the fuel rail for the cylinder to be
tested.
(6) Install capping Tool 9011 onto the rail.
(7) Remove the high pressure connector nut and
high pressure connector with Tool 9015.
(8) Remove the exhaust and intake rocker lever.
(9) Use Tool 9010 to remove the injector and cop-
per sealing washer.
(10) Install compression test Tool 9007 into the
injector bore.
(11) Connect the leakage tester and perform the
leakage test procedure on each cylinder according to
the tester manufacturer's instructions.
(12) Upon completion of the test check and erase
any engine related fault codes.
STANDARD PROCEDURE
STANDARD PROCEDURE - FORM-IN-PLACE
GASKETS AND SEALERS
There are numerous places where form-in-place
gaskets are used on the engine. Care must be taken
when applying form-in-place gaskets to assure
obtaining the desired results.Do not use form-in-
place gasket material unless specified.Bead size,
continuity, and location are of great importance. Too
thin a bead can result in leakage while too much can
result in spill-over which can break off and obstruct
fluid feed lines. A continuous bead of the proper
width is essential to obtain a leak-free gasket.
There are numerous types of form-in-place gasket
materials that are used in the engine area. Mopart
Engine RTV GEN II, MopartATF-RTV, and Mopart
Gasket Maker gasket materials, each have different
properties and can not be used in place of the other.
MOPARtENGINE RTV GEN II
MopartEngine RTV GEN II is used to seal com-
ponents exposed to engine oil. This material is a spe-
cially designed black silicone rubber RTV that
retains adhesion and sealing properties when
exposed to engine oil. Moisture in the air causes the
DRENGINE 5.9L DIESEL 9 - 239
ENGINE 5.9L DIESEL (Continued)

material to cure. This material is available in three
ounce tubes and has a shelf life of one year. After one
year this material will not properly cure. Always
inspect the package for the expiration date before
use.
MOPARtATF RTV
MopartATF RTV is a specifically designed black
silicone rubber RTV that retains adhesion and seal-
ing properties to seal components exposed to auto-
matic transmission fluid, engine coolants, and
moisture. This material is available in three ounce
tubes and has a shelf life of one year. After one year
this material will not properly cure. Always inspect
the package for the expiration date before use.
MOPARtGASKET MAKER
MopartGasket Maker is an anaerobic type gasket
material. The material cures in the absence of air
when squeezed between two metallic surfaces. It will
not cure if left in the uncovered tube. The anaerobic
material is for use between two machined surfaces.
Do not use on flexible metal flanges.
MOPARtGASKET SEALANT
MopartGasket Sealant is a slow drying, perma-
nently soft sealer. This material is recommended for
sealing threaded fittings and gaskets against leakage
of oil and coolant. Can be used on threaded and
machined parts under all temperatures. This mate-
rial is used on engines with multi-layer steel (MLS)
cylinder head gaskets. This material also will pre-
vent corrosion. MopartGasket Sealant is available in
a 13 oz. aerosol can or 4oz./16 oz. can w/applicator.
FORM-IN-PLACE GASKET AND SEALER
APPLICATION
Assembling parts using a form-in-place gasket
requires care but it's easier than using precut gas-
kets.
MopartGasket Maker material should be applied
sparingly 1 mm (0.040 in.) diameter or less of sealant
to one gasket surface. Be certain the material sur-
rounds each mounting hole. Excess material can eas-
ily be wiped off. Components should be torqued in
place within 15 minutes. The use of a locating dowel
is recommended during assembly to prevent smear-
ing material off the location.
MopartEngine RTV GEN II or ATF RTV gasket
material should be applied in a continuous bead
approximately 3 mm (0.120 in.) in diameter. All
mounting holes must be circled. For corner sealing, a
3.17 or 6.35 mm (1/8 or 1/4 in.) drop is placed in the
center of the gasket contact area. Uncured sealant
may be removed with a shop towel. Components
should be torqued in place while the sealant is still
wet to the touch (within 10 minutes). The usage of a
locating dowel is recommended during assembly to
prevent smearing material off the location.MopartGasket Sealant in an aerosol can should be
applied using a thin, even coat sprayed completely
over both surfaces to be joined, and both sides of a
gasket. Then proceed with assembly. Material in a
can w/applicator can be brushed on evenly over the
sealing surfaces. Material in an aerosol can should be
used on engines with multi-layer steel gaskets.
STANDARD PROCEDURE - REPAIR DAMAGED
OR WORN THREADS
CAUTION: Be sure that the tapped holes maintain
the original center line.
Damaged or worn threads can be repaired. Essen-
tially, this repair consists of:
²Drilling out worn or damaged threads.
²Tapping the hole with a special Heli-Coil Tap, or
equivalent.
²Installing an insert into the tapped hole to bring
the hole back to its original thread size.
STANDARD PROCEDUREÐHYDROSTATIC
LOCK
CAUTION: DO NOT use the starter motor to rotate
the crankshaft. Severe damage could occur.
When an engine is suspected of hydrostatic lock
(regardless of what caused the problem), follow the
steps below.
(1) Disconnect the negative cable(s) from the bat-
tery.
(2) Inspect air cleaner, induction system, and
intake manifold to ensure system is dry and clear of
foreign material.
(3) Place a shop towel around the fuel injectors to
catch any fluid that may possibly be under pressure
in the cylinder head. Remove the fuel injectors (Refer
to 14 - FUEL SYSTEM/FUEL INJECTION/FUEL
INJECTOR - REMOVAL).
(4) With all injectors removed, rotate the crank-
shaft using the crankshaft barring tool (PN 7471±B).
(5) Identify the fluid in the cylinders (coolant, fuel,
oil, etc.).
(6) Be sure all fluid has been removed from the
cylinders.
(7) Repair engine or components as necessary to
prevent this problem from occurring again.
(8) Squirt a small amount of engine oil into the
cylinders to lubricate the walls. This will prevent
damage on restart.
(9) Install fuel injectors (Refer to 14 - FUEL SYS-
TEM/FUEL INJECTION/FUEL INJECTOR -
INSTALLATION).
9 - 240 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)

ENGINE DATA PLATE
DESCRIPTION
The engine data plate contains specific information
that is helpful to servicing and obtaining parts for
the engine. The data plate can be found affixed to the
breather cover on the left side of the engine. Informa-
tion that can be found on the data plate includes:
²Date of Engine Manufacture
²Engine Serial Number
²Control Parts List (CPL)
²Engine Rated Horsepower
²Engine Firing Order
²Engine Displacement
²Valve Lash Reset Specifications
If the engine data plate is missing or not legible,
the engine serial number is used for engine identifi-
cation. The engine serial number is stamped on the
right side of the block, on top of the oil cooler cavity
(Fig. 5).
AIR CLEANER ELEMENT
REMOVAL
Testing Air Cleaner Element using Filter MinderŸ
Do not attempt to unnecessarily remove top
of air cleaner housing for air cleaner element
inspection on diesel engines.
The air cleaner (filter) housing is equipped with an
air Filter MinderŸ gauge (Fig. 6). This air flow
restriction gauge will determine when air cleaner ele-
ment is restricted and should be replaced.
The Filter MinderŸ consists of a diaphragm and
calibrated spring sealed inside of a plastic housing
(Fig. 7). A yellow colored disc attached to diaphragm
moves along a graduated scale on side of Filter
Minder. After the engine has been shut off, a ratch-
eting device located within Filter Minder will hold
yellow disc at highest restriction that air cleaner ele-
ment has experienced. A drop in air pressure due toan air cleaner element restriction moves diaphragm
and yellow disc will indicate size of air drop.
CAUTION: Certain engine degreasers or cleaners
may discolor or damage plastic housing of Filter
Minder. Cover and tape Filter Minder if any engine
degreasers or cleaners are to be used.
To test, turn engine off. If yellow disc (Fig. 7) has
reached red colored zone on graduated scale, air
cleaner element should be replaced. Refer to Removal
/ Installation.
Resetting Filter Minder:After air cleaner (filter)
element has been replaced, press rubber button on
top of Filter Minder (Fig. 7). This will allow yellow
colored disc to reset. After button has been pressed,
yellow disc should spring back to UP position.
If Filter Minder gauge has reached red colored
zone, and after an examination of air cleaner (filter)
element, element appears to be clean, high reading
may be due to a temporary condition such as snow
build-up at air intake. Temporary high restrictions
may also occur if air cleaner (filter) element has got-
ten wet such as during a heavy rain or snow. If this
occurs, allow element to dry out during normal
engine operation. Reset rubber button on top of Filter
Minder and retest after element has dried.
Fig. 5 Engine Serial Number Location
Fig. 6 5.9L DIESEL AIR CLEANER - FILTER
MINDERŸ
1 - CLIPS
2 - FILTER COVER
3 - FILTER MINDERŸ
4 - INLET AIR TEMPERATURE/ PRESSURE SENSOR
5 - FILTER HOUSING
9 - 248 ENGINE 5.9L DIESELDR

Filter Removal
(1) The housing cover is equipped with spring clips
(Fig. 6) and is hinged with plastic tabs. Unlatch clips
from top of air cleaner housing and tilt housing cover
up for cover removal.
(2) Remove air cleaner element from air cleaner
housing.
INSTALLATION
(1) Before installing new air cleaner element (fil-
ter), clean inside of air cleaner housing.
(2) Position air cleaner cover to tabs on front of air
cleaner housing. Latch spring clips to seal cover to
housing.
CYLINDER HEAD
DESCRIPTION
The cylinder head is constructed of cast iron and is
a one piece cross flow design with four valves per cyl-
inder. The arrangement of two intake and two
exhaust valves per cylinder allows for a centrally
located injector. The cylinder head also includes an
integral intake manifold, an integral thermostat
housing, and a longitudal fuel return rifle, which
exits at the rear of the head. The 24 valve design
also includes integrally cast valve guides and hard-
ened intake and exhaust valve seat inserts.
REMOVAL
(1) Disconnect battery negative cables.
(2) Raise vehicle on hoist.
(3) Drain engine coolant.
(4) Disconnect exhaust pipe from turbocharger
elbow.
(5) Disconnect turbocharger oil drain tube at rub-
ber hose connection. Cap off open ports to prevent
intrusion of dirt or foreign material.
(6) Lower vehicle.
(7) Disconnect air inlet temperature/pressure sen-
sor.
(8) Remove air cleaner housing and snorkel from
the vehicle. Cap off turbocharger air inlet to prevent
intrusion of dirt or foreign material.
(9) Disconnect cab heater core supply and return
hoses from the cylinder head and heater pipe.
(10) Disconnect turbocharger oil supply line at the
turbocharger end. Cap off open ports to prevent
intrusion of dirt or foreign material.
(11) Remove exhaust manifold-to-cylinder head
bolts, spacers, heat shield, retention straps, and cab
heater plumbing. Remove exhaust manifold and tur-
bocharger from the vehicle as an assembly.
(12) Remove cooling fan assembly.
(13) Remove accessory drive belt (Refer to 7 -
COOLING/ACCESSORY DRIVE/DRIVE BELTS -
REMOVAL).
(14) Remove cooling fan support from cylinder
block.
(15) Remove upper generator bolt, loosen lower
generator bolt, and rotate generator away from cylin-
der head.
(16) Disconnect radiator upper hose from the ther-
mostat housing.
(17) Disconnect the Intake Air Temperature/Mani-
fold Air Pressure, and Coolant Temperature sensor
connectors.
(18) Remove the engine harness to cylinder head
attaching bolts and P-clips at front of head.
(19) Remove the throttle linkage cover (Fig. 8).
(20) For automatic equipped vehicles only, remove
the six (6) accelerator pedal position sensor assem-
bly-to-cylinder head bracket bolts (Fig. 9) and secure
the entire assembly out of the way. Disconnect the
APPS connector (Fig. 10).It is not necessary to
disconnect the cables from the throttle control
assembly.
(21) Remove the intake air grid heater wires from
the grid heater.
(22) Remove engine oil level indicator tube attach-
ing bolt at fuel filter housing bracket and inlet air
connection..
(23) Remove the charge air cooler-to-air inlet hous-
ing pipe.
Fig. 7 FILTER MINDERŸ - 5.9L DIESEL
1 - PRESS BUTTON TO RESET
2 - YELLOW DISC
3 - RED ZONE
4 - TO AIR FILTER HOUSING
5 - FILTER MINDER
DRENGINE 5.9L DIESEL 9 - 249
AIR CLEANER ELEMENT (Continued)

(32) Disconnect fuel heater, water in fuel sensor,
and fuel lift pump connectors.
(33) Remove the fuel filter assembly-to-cylinder
head bolts and remove filter assembly from vehicle.
(34) Remove wire harness P-clip from cylinder
head (located behind filter housing).
(35) Remove the cylinder head cover(Refer to 9 -
ENGINE/CYLINDER HEAD/CYLINDER HEAD
COVER(S) - REMOVAL).
(36) Disconnect rocker housing injector harness
connectors.
(37) Remove injector harness nuts from injectors.
(38) Remove the rocker levers (Fig. 11), cross
heads and push rods (Fig. 12). Mark each component
so they can be installed in their original positions.
NOTE: The #5 cylinder exhaust and the #6 cylinder
intake and exhaust push rods are removed by lift-
ing them up and through the provided cowl panel
access holes. Remove the rubber plugs to expose
these relief holes.
(39) Remove the fuel return line and banjo bolt at
the rear of the cylinder head. Be careful not to drop
the two (2) sealing washers.
(40) Remove the fuel injectors (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
REMOVAL).
(41) Remove rocker housing bolts and rocker hous-
ing and gasket.(42) Reinstall the engine lift bracket at the rear of
cylinder head. Torque to 77 N´m (57 ft. lbs.).
(43) Remove twenty six (26) cylinder head-to-block
bolts.
(44) Attach an engine lift crane to engine lift
brackets and lift cylinder head off engine and out of
vehicle.
(45) Remove the head gasket and inspect for fail-
ure.
CLEANING
CLEANINGÐCYLINDER HEAD
CAUTION: Do not wire brush head surface while
fuel injectors are still installed. Fuel injector dam-
age can result.
Remove fuel injector before cleaning (if not already
removed during cylinder head removal).
Clean the carbon from the injector nozzle seat with
a nylon or brass brush.
Scrape the gasket residue from all gasket surfaces.
Wash the cylinder head in hot soapy water solution
(88ÉC or 140ÉF).
After rinsing, use compressed air to dry the cylin-
der head.
Polish the gasket surface with 400 grit paper. Use
an orbital sander or sanding block to maintain a flat
surface.
CLEANINGÐCROSSHEADS
Clean all crossheads in a suitable solvent. If neces-
sary, use a wire brush or wheel to remove stubborn
deposits. Rinse in hot water and blow dry with com-
pressed air.
Fig. 11 Rocker Arm and Pedestal Removal
1 - ROCKER ARM
2 - PEDESTAL
Fig. 12 Push Rod Removal
DRENGINE 5.9L DIESEL 9 - 251
CYLINDER HEAD (Continued)