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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 ªADDº
mark. The total capacity from the low mark to the high
mark is 2 quarts (1.9 liters).
CAUTION!
Overfilling or underfilling the crankcase will cause
oil aeration or loss of oil pressure. This could damage
your engine.
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Never operate the engine with oil level below the ªADDº
mark or above the upper ªSAFEº mark.
Change Engine Oil (6.7L Diesel Engine)
Follow the 6.7L Diesel Maintenance Schedule for recom-
mended engine oil change intervals.
Engine Oil Selection (6.7L Diesel Engines)
For best performance and maximum protection under all
types of operating conditions, the manufacturer only
recommends engine oils that are API CJ-4 certified and
meet the requirements of DaimlerChrysler. Use Mopart
or an equivalent oil meeting DaimlerChrysler Material
Standards MS-10902. Products meeting CumminstCES
20081 may also be used. The identification of these
engine oils are typically located on the back of the oil
container.
American Petroleum Institute (API) Engine Oil
Identification Symbol
This symbol means that the oil has
been certified by the American Petro-
leum Institute (API). The manufacture
only recommends API CJ-4 certified
engine oils.
Oils with a high ash content may produce deposits on
valves that can progress to guttering and valve burning.
A maximum sulfated ash content of 1.00 mass % is
recommended for all oil used in the engine.
The same oil change interval is to be followed for
synthetic oil as for petroleum based oil. Also, synthetic oil
must meet the same performance specifications as petro-
leum oil.
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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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