Mike,
The ones that came up under my local dealer do say synthetic. There's one that says "diesel truck", synthetic may be extra $89.95, and there's one that says "diesel truck, synthetic oil for $98.95. I think the first one refers to the Cummins and second is Ecodiesel. Funny, I was at the dealer today (getting a new Catalytic converter, due to CEL) and I asked them how much an oil change for this truck would be. (I got the first one free so I didn't know how much they charged) He says, "well, they are all different. Some take special oil, some take 5 quarts, some take more, so they are all different prices. I said, yeah, I get that but how much is an oil change for my truck? He just keeps repeating, "I don't know, they are all different". I said, so are you telling me that you can't look it up and tell me how much? He says "he's not privy to that information, only the diesel tech that works on the truck would know?? I started getting loud at that point and realized I should just let it go since I was in the process of leaving my truck with these guys. Is that bizarre or is it just me? If I needed an oil change today, what would they have charged?.....lol. Still love the truck..btw.