IMHO:
Best bets:
Dodge - '03 to '06. Has the CRD, awsome running engine.
Chevy - Pretty much any Duramax after about '01 due to some early head gasket problems. My only gripe is that the frame is only like, 11" off the deck!
Ford - Late '99 to late '00 for 7.3's, '05-'06 for 6.0.
Automatics are historically weak in all brands except for the Allison and the Torque shift on the Ford 6.0's.
As stated, the 24v dodges with the VP44 have been known to fail and have lift pump problems.
Now, these are just my experiences. Of course, there will always be someone who jumps up and says "I never had any trouble with blah, blah, blah..." You know the story.
And, oh yeah, I would NEVER have another truck without 4WD, they suck out loud on snow.