[mechanic17]

I'm seriously considering buying a used type I or III ambulance soon for a camper conversion. Mid-late 90s vintage is about what I can afford. The most common seems to be the ford f350/450 chassis with a 7.3 TD powerstroke. There are some Dodge 5.9 TD Cummins out there, and a few GMCs.

I do intend to load the thing up with my junk, but won't be towing a big boat or anything, so I'm more interested in powertrain reliability/economy than ultimate power, and I don't forsee modifying it.

I'm sold on a diesel for the mileage and reliability--problem is I know nothing about them. Never owned one. I read a lot of tranny replacement stories. SO, given that I'm starting from square-one, can anyone give their recommendation for best combo?

I'm assuming that any heavy chassis by the big three will do, but if someone wants to warn me about weak frames, rear-ends, electrical issues, consider me a welcoming blank slate. I do plan on buying down south to avoid something rusty underneath. Thanks in advance.