Replacing oil without changing filter...
 

Some idiot put 15-40 in my 300d the other day. Ok it was me. I'm about to switch it out with some 5-30 before the temperature drops.
What I'm wondering is, Since I just replaced the filter, (4 days ago),
Is it cool to just drain and refill without changing the filter?

I don't see why not, but I thought I would ask anyhow...

Tx

yeah,,,,
 

that's what i would do...

Good-o.

Good luck on getting Detroit to make that electric car... we're all counting on you.
:)

isnt 5-30 a little on the low side for a diesel? would something in the 5w-40 range be more appropriate? just asking here, my gasser runs diesel oil all the time (15w-40 summer 5w-40 winter)

Yeah, it's gotta be 40 weight. 5 or 0W 40 in the winter is good.

remove cover and filter
 

To vent it so that drains too. Then reinstall "old" filter.

You don't say where you are or how cold it gets.
I run 15-40 year round but it doesn't often get below freezing. If it seems too cold, I'll use the heater or drive a gasser.

5w30 is not diesel rated oil. You need at least a diesel approved 5w40 synthetic. It makes a huge difference in cold weather starting vs. 15w40.

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.