Auto Parts: 2004 dogde cummins oil change, cummins engine, dark oil

Question
QUESTION:  Could my 2004 cummins deisel oil be black after driving home from getting the oil changed? Maximum 3 miles ? I am questioning whether it was actually done or not. I checked it at home and it was very black? Is that possible ?

ANSWER:      The oils used in diesels have some additives that color the oil very black.  I used to get people asking me about it 'cause there would be a black residue on the bottom of the bottle.  It was such a problem that the oil company started making the bottles out of black plastic so you wouldn't see the residue when you looked in the empty bottle.  Between this and soot (which you probably don't have a problem with, but a lot of older non-computerized diesels did) you get a nice, dark color.  Check the oil in the morning with the engine cold (before you start it) and I think you will see a nice golden color, the black stuff will have settled on the bottom of the oil pan.  If you really have some doubt about him changing your oil, mark the drain plug with Wite-out or a similar long-lasting mark and check it after the next change.

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QUESTION: Well this oil is Black on the cloth I used to wipe it with .Black ,black not a dark oil color .The truck had been sitting all night and was not started before I checked it,was the oil changed in your opinion?

Answer
    Well, I am beginning to wonder.  I think I would go out and buy a quart of the brand that they claim to have used and see what is in the bottle.  Does the oil filter look brand-new?  Again, soot in oil is black.  It's what they use to make black ink.  Before you go back and accuse them of malfeasance you might want to consult some other owners of similar trucks, or maybe the dealer.  Not changing the oil is a good way to make extra money on oil changes, but I can't imagine a reputable shop willing to do such a thing.  And, if they're not reputable, you shouldn't be taking your very expensive Cummins engine to them for service.  You might also want to smell the oil on the dipstick.  New oil should smell like the oil in the bottle.  Old oil will have all sorts of nasty compounds in it and have a sour smell.