My truck has the legendary "Cummins", I have not heard of a "Cummings".
I only have 7k miles and I know from past experience it is not yet broken in.
Everything that I have heard said not to "switch" to synthetic in a CTD until 15k to 20k miles to insure a good break-in. I have had all 3...
I have had all three generation Dodges with an automatic and wouldn't have anything else.
What's a Cummings?
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