I will be taking my truck back to the dealership for fuel in the crank. Before I take my truck back to the dealership I want to get an oil sample for anaylsis. Question: Can I take the sample after the truck has been sitting.(Does the diesel and oil separte or do they stay mixed. It has been sitting since I noticed what happened. It is being towed tonight and I would like a anaylsis done for my own records. I want it to be as accurate as possible.

Thanks in advance!

Every lab I've spoken with wants the oil collected warm. That way it contains all the ingredients, even those that would normally settle out. But you have to be sure it's a "clean sample" or in other words, just oil from the crankcase, no dirt, grease or other contaminent.
Doug