Yeah being this is my first diesel the 5w 40 oil through me all i could find its for cold weather . but cold like Pittsburgh or cold like Alaska lol
For all trucks, regardless of model year, located in areas where the ambient temperatures routinely
fall below 0°F (-18°C) during the winter, it is required to use 5W-40 synthetic engine oil that
meets US Material Standard MS-10902, and API CJ-4. Oils that meet this requirement can be found
through Mopar, as well as Shell in the Rotella and the Rimula families. Although this grade of oil is
required in colder climate areas, it is also safe to use during the summer months, and in warmer
climates as well.
However, for vehicles normally located in areas that routinely stay above 0°F (-18°C), there are two
grades of engine oil recommended depending on the model year of the vehicle:
• 2018 model year, and older vehicles, it is recommended to use 15W-40 engine oil such as
the Mopar, Shell Rotella and Shell Rimula branded oils that meets US Material Standard
MS-10902 and the API CJ-4 engine oil.
• 2019 model year, and newer vehicles, it is recommended to use 10W-30 engine oil such as
Mopar, Shell Rotella and Shell Rimula that meets FCA Material Standard MS-10902, and the
API CK-4 engine oil category is required. Products meeting Cummins CES 20081 may also be
used