Page 409 of 552
ENGINE COMPARTMENT — 5.9L DIESEL ENGINE
MAINTAINING YOUR VEHICLE 409
7
Page 410 of 552

ONBOARD DIAGNOSTIC SYSTEM (OBD II)
Vehicles equipped with California emissions controls
have a sophisticated onboard diagnostic system called
OBDII. This system monitors the performance of the
emissions, engine, and automatic transmission control
systems. When these systems are operating properly,
your vehicle will provide excellent performance and fuel
economy, as well as engine emissions well within current
government regulations.
If any of these systems require service, the OBD II system
will turn on the “Malfunction Indicator Light.” It will
also store diagnostic codes and other information to
assist your service technician in making repairs. Al-
though your vehicle will usually be driveable and not
need towing, see your dealer for service as soon as
possible.CAUTION!
Prolonged driving with the “Malfunction Indicator
Light” on could cause further damage to the emission
control system. It could also affect fuel economy and
driveability. The vehicle must be serviced before any
emissions tests can be performed.
If the “Malfunction Indicator Light” is flashing,
severe catalytic converter damage and power loss
will soon occur. Immediate service is required.
REPLACEMENT PARTS
Use of genuine Moparparts for normal/scheduled
maintenance and repairs is highly recommended to in-
sure the designed performance. Damage or failures
caused by the use of non-Mopar parts for maintenance
and repairs will not be covered by the manufacturer’s
warranty.
410 MAINTAINING YOUR VEHICLE
Page 411 of 552

ENGINE DATA PLATE
Use the information from the engine data plate when
discussing service or sourcing parts for your engine. The
engine data plate is located on the intake side of the
breather cover.
DEALER SERVICE
Your dealer has the qualified service personnel, special
tools and equipment to perform all service operations in
an expert manner. Service manuals are available which
include detailed service information for your vehicle.
Refer to these manuals before attempting any procedure
yourself.
NOTE:Intentional tampering with emissions control
systems can result in civil penalties being assessed
against you.
WARNING!
You can be badly injured working on or around a
motor vehicle. Do only that service work for which you
have the knowledge and the proper equipment. If you
have any doubt about your ability to perform a service
job, take your vehicle to a competent mechanic.
SERVICE INFORMATION
Mopar Fluids, Lubricants and Parts are available from
your dealer and will help you keep your vehicle operat-
ing at its best. Your dealer also has the qualified service
personnel, special tools and equipment to perform all
service operations in an expert manner. Service manuals
are available which include detailed service information
for your vehicle. Refer to these manuals before attempt-
ing any procedure yourself. See Service Publications
information at the back of this manual.
MAINTAINING YOUR VEHICLE 411
7
Page 412 of 552

CAUTION!
To maintain your vehicle safely follow these
guidelines:
•Watch your vehicle’s mileage and check yourMainte-
nance Schedulesregularly for required servicing. Ex-
cessive wear or damage to certain vehicle components
can result if required services are not performed.
•If you have your vehicle undercoated, inspect for
undercoating material on the propeller shafts. Such
material could cause the shafts to become unbalanced
and result in drivetrain vibrations. Remove any under-
coating with solvent.
•If you have your vehicle undercoated, make sure no
undercoating material is sprayed on the exhaust sys-
tem or components of the seat belt system.NOTE:It is not possible for the manufacturer and
Cummins, Inc. to anticipate every possible circumstance
that can involve a potential hazard.
WARNING!
To maintain your vehicle safely and avoid personal
injury, follow these guidelines:
•Never spray or pour diesel fuel, flammable liquid or
starting fluids (ether) into the air cleaner assembly, air
intake piping or turbocharger inlet in an attempt to
start the vehicle, unintended engine acceleration may
occur.
•Do not use alcohol or gasoline as a fuel blending agent.
They can be unstable under certain conditions and be
hazardous or explosive when mixed with diesel fuel.
412 MAINTAINING YOUR VEHICLE
Page 413 of 552

•If an engine has been operating and the coolant is hot,
allow the engine to cool before you slowly loosen the
filler cap and relieve the pressure from the cooling
system.
•To avoid burns, remember that the engine components
will stay hot after the engine is shut off.
•Do not use gasoline or other flammable materials to
clean parts. Always use approved cleaning solvents.
•Relieve all pressure in the fuel, oil and cooling systems
before any lines, fittings or related items are removed
or disconnected. Be alert for possible pressure when
disconnecting any device from a system that utilizes
pressure. Do not check for pressure leaks with your
hand. High pressure oil or fuel can cause personal
injury.
WARNING!
Do not open the high pressure fuel system with the
engine running. Engine operation causes high fuel
pressure. High pressure fuel spray can cause serious
injury or death.
•Important:All maintenance other than that listed in
this manual, as well as some procedures listed here,
MUSTbe performed by your local Dodge Truck
Dealer. Your authorized Dodge Dealer has been
trained and has the necessary parts to maintain your
engine.
MAINTAINING YOUR VEHICLE 413
7
Page 414 of 552

MAINTENANCE PROCEDURES
The pages that follow contain therequiredmaintenance
services determined by the engineers who designed your
vehicle.
Besides the maintenance items for which there are fixed
maintenance intervals, there are other items that should
operate satisfactorily without periodic maintenance.
However, if a malfunction of these items does occur, it
could adversely affect the engine or vehicle performance.
These items should be inspected if a malfunction is
observed or suspected.
Engine Oil
Checking Oil Level
To assure proper lubrication of your vehicle’s engine, the
engine oil must be maintained at the correct level. Check
the oil level at regular intervals. The best time to check
the oil level is before starting the engine after it has been
parked overnight. When checking oil after operating the
engine, first ensure the engine is at full operating tem-
perature, then wait at least 30 minutes after engine
shutdown to check the oil.
Checking the vehicle while it’s on level ground will also
improve the accuracy of the oil level readings. Add oil
only when the level on the dipstick is below the “ADD”
mark. The total capacity from the low mark to the high
mark is 2 quarts (1.9 liters).
414 MAINTAINING YOUR VEHICLE
Page 415 of 552
CAUTION!
Overfilling or underfilling the crankcase will cause
oil aeration or loss of oil pressure. This could damage
your engine.Never operate the engine with oil level below the “ADD”
mark or above the upper “SAFE” mark.Change Engine Oil (5.9L Diesel Engine)
Road conditions as well as your kind of driving affect the
interval at which your oil should be changed. Check the
following to determine if any apply to you:
•Frequent short trips where the engine does not achieve
full operating temperature (operating temperature de-
fined as 190° F (66° C ) coolant temperature).
•Extensive engine idling (over 10 minutes per hour of
operation) at ambient temperatures less than 32° F (0°
C).
•Driving in dusty conditions.
•Frequent trailer towing.
•Taxi, police, or delivery service (commercial service).
•Off-road or desert operation.
MAINTAINING YOUR VEHICLE 415
7
Page 416 of 552

•Extensive operation at high engine speeds (greater
than 2900 rpm) and loads (greater than 70% throttle).
IfANYof these apply to you, then change your engine oil
at every interval shown in scheduleBof theMainte-
nance Schedulessection of this manual.
If none of these apply to you, then change your engine oil
at every interval shown on scheduleAof theMainte-
nance Schedulessection of this manual.
NOTE:Most vehicles are operated under the conditions
listed for ScheduleB.
Change Engine Oil (6.7L Diesel Engine)
Follow the 6.7L Diesel Maintenance Schedule for recom-
mended engine oil change intervals.
Engine Oil Selection (5.9L Diesel Engine)
1. Engine Oil Quality
Use only oils conforming to API Ser-
vice CI-4. A sulfated ash limit is speci-
fied for lubrication oil used in Cum-
mins engines. Oils with a high ash
content may produce deposits on
valves that can progress to guttering
and valve burning. A maximum sul-
fated ash content of 1.85 mass % is recommended for all
oil used in the engine.
416 MAINTAINING YOUR VEHICLE