I have a 2000 F350 dually with the 7.3 powerstroke (my favorite diesel engine). I bought it used with 270,000 miles and has been running great. The main thing going against diesels is that parts are a lot more expensive than parts for gas motors. But i attribute that to diesels generally lasting longer than gas engines. I would stay away from anything that requires DEF fluid (diesel exhaust fluid). The DEF systems can be rather temperamental and can cause headaches to new diesel owners. There are a bunch of little details that you have with diesels that you don't with gasoline motors. Such as EGTs (Exhaust gas temps), diesel fuel gelling in cold weather, low lubricity fuel issues, etc.. But once you know what to look for it is pretty easy to maintain a diesel. The 3 motors i would recommend would be the 5.9 12valve Cummins, the 7.3 Powerstroke, and the 7.3 IDI. All 3 are very good motors and have a large community behind them. Stay away from the 6.0 and 6.4 powerstrokes, they can make a lot of power but are not good for someone new to diesels.

iliketruks I have owned a 2014 Ford F-350 with the 6.7 Diesel and now a 2017 Ram 2500 with a 6.7 Cummins Diesel. Neither have had any engine work required. I am 48 and have grown up around diesels and heavy equipment my entire life. Cummins, Caterpillar, Detroit 2 and 4 stroke, Paccar, Volvo... From the 1970s all the way to current models. My dad was a long haul truck driver for over 60 years. Here is my advise;

Any Diesel is more expensive than a gas engine because they are made to work and tolerate lugging. Gas engines will lug but don't really enjoy it. They tend to only work at high RPM's are less efficient (poor mileage). Higher RPM's=more wear and heat.

Anything before say 2001 is good but getting old and hard to find one not beat to death. Anything mid 2000's I would stay away from (first attempt at emissions). Anything after 2011 is excellent and extremely reliable and powerful as long as,

1. The previous owner or you don't reprogram/tune it

2. Neglect maintenance = oil, fuel filters especially

3. You don't let it idle and only drive in town

4. Don't drive it like a sports car

5. Use quality fuel and DEF

6. Pull with it.

Without a doubt from 2011 on, diesel engines being use by Ford, Ram, and GM are all excellent. The have far more torque and HP then anything built before. All 3 will go 200-300K miles without much work. I live in North Dakota and -20F mine have always started. Fuel only jells if it is not properly treated cold climates=winter blend. Low lubricity is not an issue with electronically controlled injectors. They no longer operate on oil pressure. 

The nightmare's you hear about are mostly wife's tails as long as you adhere to the 3 items I listed about. Those old 5.9's and 7.3's are reliable but not very powerful, dirty and leak oil. 

Big question is... Do you really need a diesel or only want a diesel. Most people its the latter. Good luck!