If you want to try burning synthetic oil, pour a couple of quarts into your truck's fuel tank and see what happens. Some burns fine while others drip out the exhaust totally unburned. That way there is no great loss if what you have doesn't burn well. I can tell you from experience that Amsoil does NOT burn!
Personally, I burn a little DexronIII ATF, but in small quantities. I will use up to a quart in a gallon of used oil in a tank of fuel. DO NOT use gear lube or hydralic oil or oil with STP like additives! They seem to gum things up more than lube everything and then burn!!!
It would be handy to just dump the oil in your fuel storage and then pump it into your truck. But, the oil settles out of the diesel if let set. I fear you would have almost pure oil in the bottom of your storage tank and diesel with very little oil in the top! I carry the used oil in gallon jugs and dump in what I need after filling (but not topping) the tank. The movement of the truck keeps things mixed in the fuel tank. I do not make "rocket science" out of adding oil to the fuel! A little variation from tank to tank doesn't seem to matter!