Ok first, great site. I used it a few years back to do research before I bought my F350 and F250, the 350 is a dedicated work truck with a dump bed on it the 250 is personal/work.
I searched the forum for an answer but did not find one so PLEASE HELP!
The problem I'm having is with the 350. It is a 2006 5.4 dually with a dump bed. A couple years ago it started intermittently charging the battery. It would start fine, then drive to the job and try to start it and nothing, I would have to jump it.Then drive to the next job and it would be fine. At first I thought battery and replaced it. That worked for awhile then it did it again. I disconnected the dump bed and the problem still occurred. I checked the connections to the alternator and they seemed fine but after I did that I had no problems for a few days but then they came back. Gauges and everything else works fine work fine.
Thanks in advance

 

Most car parts places will load test your alternator for free. At first blush it just sounds like a bad alternator.

A fully charged battery will run the vehicle for quite a while even when the alternator isn't working.