5W40 or 15W40 in 6.7 CTD?
So the owner's manual in my 2015 Ram says to use 15W40 oil in the 6.7 Cummins diesel, unless the temp is going to routinely be below 0*, in which case you should use 5W40. Here on Long Island, the ...
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I am always in favor of doing what the owner's manual, written by the people who designed and built your vehicle, says to do rather than people on an internet forum say to do.
