Depends on the day!
If the oil is anywhere near it's replacement window I'd go ahead and change it.
Do you have a block heater? How about adding a gallon of gas to a full tank of diesel?NordRhein said:Diesels are not gas engines, slow running is their forte. Gas engines on the other hand like to foul their plugs and dilute their oil. A diesels crankcase oil is similar to it's fuel! Diesels have no plugs to foul - glow plugs don't count. In fact if you live with a diesel in Alaska you will soon find that you let it run all night pulled into a snowbank or it won't start.