Oil change for my truck at Ontario GM dealers runs at about $59 vs around $35 for gas powered. The reason, or the main reason for diesel engines being built more heavily is that diesel's have higher cylinder pressures, combined with the fact they are usually used for work. In reg's to fuel economy, the biggest difference is when you are working the vehicle. Towing a heavy trailer with a gasser will probably reduce your economy by 40% vs 15-20% with the desel(those are just my own personal guestimations). If you'r working the truck a fair bit, I'd consider the diesel. Diesel was cheaper than gas around here for years but it's jumped ahead of gas right now due to high demand for diesel fuel....at least thats what the guy at DOST Petroleum told me.