Well as indicated in the title, I've got an intermittent problem with my [2005 6.0 - 57,000mi]. 3 times now
September - Started truck numerous times all afternoon, driving around farm, pulled gooseneck 15km to town, stopped off at the bank for 15 minutes with truck off, came back truck won't start, just turns over and over and over and over, no fire. Mechanic friend from local Dodge dealer swung by with his computer, wasn't building pressure. 5pm. Called a different friend, got dad to borrow his Dodge, met me at the truck at 8pm, fully expecting to tow my truck out from under my gooseneck. Truck started like a champ (8pm). Unhooked trailer, trailer to Dodge, dropped my truck off at the mechanic (20km away, drove it like it was stolen to try to heat it up), shut off truck and restarted it flawlessly 5 times at mechanics. Left it with him, he replaced a ??regulator screen?? which was torn.
December 1st - Truck was parked for several hours out in the cold, drove through the city and stopped at a fast food joint, turned truck off in the drive through (the lady in the intercom box told me to), ordered, truck wouldn't start. Employees of restaurant and myself pushed me out of the drivethrough lane. 20 minutes later truck fired up perfectly. Drove home, parked at 2am in the garage, by 7am it started perfectly.
January 22nd - Drove truck 70km, shut it off for 10 minutes, drove truck 5km, shut it off for 10 minutes, truck would not start. Would not start from 3pm until 7pm. 7pm started perfectly.
Sometimes the truck takes a long time to fire (10 seconds of cranking?), usually if you've just shut it off within the last 5 minutes, but otherwise it's perfect.
Mechanic basically wants me to leave it with him, he will drive it around until it happens to him.