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Engine Oil Viscosity (SAE Grade)
Use SAE 15W-40 Engine Oil that meets
DaimlerChrysler Materials Standard MS-10902 and the
API CJ-4 engine oil category.
Engine oil not designated by the DaimlerChrysler or
CumminstMaterial Standards and API CJ-4 should not
be used, engine and exhaust system durability may be
compromised. For lower temperature operation SAE
5W-40 engine oils may be used. These oils must meet the
same requirements as stated previously. The engine oil
filler cap also shows the recommended engine oil viscos-
ity for your engine. For information on engine oil filler
cap location, refer to the ªEngine Compartmentº illustra-
tion in this section.
Synthetic Engine Oils
You may use synthetic engine oils provided the recom-
mended oil quality requirements are met, and the recom-
mended maintenance intervals for oil and filter changes
are followed.
Materials Added to Engine Oil
The manufacturer strongly recommends against the ad-
dition of any additives (other than leak detection dyes or
lube odorants) to the engine oil. Engine oil is an engi-
neered product and it's performance may be impaired by
supplemental additives.
NOTE:The manufacturer offers a lube odorant (Mopart
Diesel Fresh) for diesel engines crankcases. The lube
odorant is recommended by the manufacturer to reduce
the sulfur smell that may occur during engine idling.
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Engine Oil Filter
Refer to Fluids, Lubricants and Genuine Parts for the
correct part number. The engine oil filter should be
changed ateveryengine oil change.
Engine Oil And Filter Ð Change
Operate the engine until the coolant temperature reaches
140ÉF (60ÉC). Shut the engine OFF. Remove the oil drain
plug.
Use a container that can hold at least 12 quarts (11.3
Liters) to hold the used oil.
Always check the condition of the used oil. This can give
you an indication of some engine problems that might
exist.
²Thin, black oil indicates fuel dilution.
²Milky discoloration indicates coolant dilution.Clean the area around the oil filter base. Remove the filter
from the underside of the vehicle using a cap style oil
filter wrench.
Clean the gasket surface of the filter mount. The filter
gasket can stick on the filter mount. Make sure it is
removed.
Change the engine oil filter with every engine oil change.
Only a high quality Mopartfilter should be used to
assure most efficient service.
CAUTION!
The filtering medium of other aftermarket filters
may disintegrate. Debris from failed filters may plug
the piston oil cooling nozzles, resulting in scuffed
pistons and engine failure.
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CAUTION!
Fill the oil filter element with clean oil before instal-
lation. Use the same type oil that will be used in the
engine. When filling the oil filter, prevent foreign
material from falling into the filter. Severe engine
damage may occur.
Apply a light film of lubricating oil to the sealing surface
of the filter gasket before installing the filter.
CAUTION!
Overtightening may distort the threads or damage
the filter element seal.Install the filter as specified by the filter manufacturer.
Turn the filter 3/4 to one full turn after making contact
with the gasket.
Check the condition of the threads and sealing surface on
the oil pan and drain plug.
Install the drain plug and sealing washer and tighten to
37 ft-lbs. (50 N´m).
Use only high-quality multi-grade lubricating oil in your
CumminstDiesel Engine. Choose the correct oil for your
operating conditions as outlined in the Selection of
Engine Oil.
CumminstTurbo Diesel
Fill the engine with the correct grade of new oil. The
engine capacity is 11 quarts (10.4 liters) in the crankcase
and 1 quart (.95 liter) in the lubricating oil filter.
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Start the engine and operate it at idle for several minutes.
Check for leaks at the lubricating oil filter and oil pan
drain plug.
Run the engine until it has reached operating tempera-
ture, stop the engine. Wait approximately 15 minutes to
let the oil in the upper parts of the engine drain back to
the pan. Check the oil level again.
Add oil as necessary to bring the level to the ªSAFEº
mark on the dipstick.
Disposing Of Used Engine Oil And Filter
Care should be taken in disposing of used engine oil and
oil filters from your vehicle. Used oil and oil filters,
indiscriminately discarded, can present a problem to the
environment. Contact your authorized dealer, service
station, or governmental agency for advice on how and
where used oil and oil filters can be safely discarded in
your area.
Drive Belt
Inspection
Check the belt for intersecting cracks.
²Transverse (across the belt width) cracks are accept-
able.
²Longitudinal (direction of belt length) cracks that
intersect with transverse cracks are NOT acceptable.
Replace the belt if it has unacceptable cracks, is frayed or
has pieces of material missing.
The engine speed sensor, located near the damper, should
be inspected for damage if a belt is frayed.
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Engine Air Cleaner Filter (6.7L Diesel Engines)
CAUTION!
All air entering the engine intake must be filtered.
The abrasive particles in unfiltered air will cause
rapid wear to engine components.
The condition of the air cleaner filter is monitored by the
Engine Control Module. The Electronic Vehicle Informa-
tion Center (EVIC) will display SERVICE AIR FILTER
when service is required.
Do not remove the top of the air filter housing to
inspect the filter element on your diesel engine under
normal operating conditions.
The EVIC message SERVICE AIR FILTER could be dis-
played periodically. This is because engine air flow
requirements change based on driving conditions. As thefilter becomes more restrictive and air flow requirements
increase the EVIC message SERVICE AIR FILTER will be
displayed. The message may not be displayed in subse-
quent drive cycles if the same conditions are not met. The
air filter element should be replaced within 250 miles
from the first time this message is displayed to ensure
proper engine operation during all driving conditions.
The air filter housing on your vehicle may also come
equipped with a Filter MinderŸ. This is an air flow
restriction gauge that will indicate when the filter ele-
ment needs to be replaced.
CAUTION!
Driving with a restricted air filter can cause engine
damage.
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If the vehicle experiences a sudden loss of engine power
when being driven in heavy snow, rain or when plowing
snow, and the EVIC message center states SERVICE AIR
FILTER or the Filter MinderŸ (if equipped) is showing a
plugged filter, then visually inspect the air filter for
snow/ice build up or extreme water saturation. If the air
filter is not damaged, remove all snow/ice and reinstall
air filter. If the air filter is damaged, replace filter element.
NOTE:The air filter housing contains a Mass Air Flow
sensor. This sensor is critical to proper engine operation
and component longevity. Any damage or modification
to this sensor could result in major engine and/or
exhaust aftertreatment damage. This includes the use of
non-approved air filters. Use only Mopartapproved air
filters or equivalent.A visual inspection of the air cleaner filter element is
never recommended under normal circumstances. A
badly restricted element may appear clean while a soiled
element may be quite effective in filtering particles
without restricting air flow. Rely on the Engine Control
Module or the Filter MinderŸ (if equipped), to deter-
mine when a filter change is necessary.
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The clear plastic housing on the Filter MinderŸ (If
Equipped), allows you to view the amount of air pressure
drop across the filter element. It consists of a diaphragm
and a calibrated spring sealed inside the plastic housing.
As the air cleaner filter becomes clogged and air pressure
drop across the filter element increases, a yellow disc
travels along a graduated scale on the side of the Filter
MinderŸ.
The yellow disc will always show the greatest restriction
experienced by the filter element. When the disc reaches
the red zone, the filter element may need to be replaced.
There is no other time or mileage interval for changing
the air cleaner filter element.
After a new filter element is inserted, press the rubber
button on the top of the Filter MinderŸ (if equipped).
This action will reset the yellow disc to the clean position.CAUTION!
When using an engine cleaner or a degreaser, be sure
to wrap and tape the Filter MinderŸ to protect the
plastic housing from damage and discoloration.
CAUTION!
Many aftermarket performance air filter elements do
not adequately filter the air entering the engine. Use
of such filters can severely damage your engine.
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Draining Fuel/Water Separator Filter (6.7L Diesel
Engine)
CAUTION!
Do not drain the fuel/water separator filter when the
engine is running.
CAUTION!
Do not prefill the fuel filter when installing a new
fuel filter. There is a possibility that debris could be
introduced into the fuel filter during this action. It is
best to install the filter dry and allow the in-tank lift
pump to prime the fuel system.
NOTE:The fuel filter and water separator assembly is
located on the driver's side of the engine. The best access
to the water drain valve is through the driver's side
wheel well.
NOTE:If water is detected in the water separator while
the engine is running or while the key is in the on
position, the WATER IN FUEL LIGHT will illuminate
and an audible chime will be heard five times. At this
point you should stop the engine and drain the water
from the separator.
422 MAINTAINING YOUR VEHICLE