I agree with PawoSD.......I do not believe there are any 5W30 weight oils that are API Diesel rated. They are all 40 weight oils in the US. So look for a 5W40 that has a API rating of CI, CF or CJ4 for winter use. All the ratings beginning with a "C" are for Diesel.

You should be fine reusing the filter you installed just days ago.

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FRED

Daily Driver: 98 E300TD 199K
Hobby Car: 69 Austin Mini
Past Diesels: 84 300SD, 312K
87 300SDL, 251K
94 Chev. K-1500 6.5Ltr.TD, 373K