Dodge 2015 RAM Owner's Manual page 285

CAUTION!
Failure to use SAE 5W-40 synthetic engine oil in
ambient temperatures below 0°F (-18°C) could result
in severe engine damage.
MAINTAINING YOUR VEHICLE 283
Engine oil not designated by the Chrysler or Cummins®
Material Standards and API CJ-4 should not be used, as
engine and exhaust system durability may be compro-
mised. The engine oil filler cap also shows the recom-
mended engine oil viscosity for your engine. For infor-
mation on engine oil filler cap location, refer to "Engine
Compartment" in "Maintaining Your Vehicle" for further
information.
Synthetic Engine Oils
You may use synthetic engine oils if the recommended oil
quality requirements are met and the recommended
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) to
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