Dodge Ram 3500 Owner's Manual page 409

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.
Engine Oil Viscosity (SAE Grade)
Use SAE 15W-40 Engine
DaimlerChrysler Materials Standard MS-10902 and the
API CJ-4 engine oil category.
Engine oil not designated by the DaimlerChrysler or
Cummins Material 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. Your engine oil
filler cap also shows the recommended engine oil viscos-
ity for your vehicle.
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
Oil that meets The manufacture strongly recommends against the addi-
tion 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 (Mopar
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.
MAINTAINING YOUR VEHICLE 409
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