Decided to upgrade the work van from 2001 Ford E350 7.3 diesel to an 07 GMC Savannah diesel. Had to drive it 400 miles home, it has way better suspension and ride than the ford van. Of course you all want to know the MPG on the trip right? Well i had to go 400 miles down and back in same day so i was doing the full 80 mph speed limit whole time. It used 2/3 of a tank of diesel at a hand calculated average of 19.55. The ford would be lucky to get 17-18 at such high speeds. A friend wanted the 7.3 van ever since i first got it, the tags were up, and this one was reasonable so i went for it. The duramax i believe is an LLY engine with no DPF or DEF emissions stuff. Planning on keeping it on Rotella 15w40 as previous owner used. It starts up like instantly and is glass smooth. The 7.3 would really rumble compared to this. Considering changing trans fluid (4L85E) to the new Dexron HP Mobil 1 equivalent that my 8 speed truck takes. Its supposed to be backwards compatible to the specified Dex VI for this year. I guess its just a little fancier and i happen to have a large stash of it on hand.