Its mostly personal preference really. I have had all of the above (including a couple dodges that I won't do again)
All of the 3/4 ton trucks and vans are pretty much equally capable, with the exception of the Chevys in some areas. Chevy vans don't really have what it takes in a few key areas. Their long wheelbase makes for steady towing, but don't (I really mean don't) go old enough to gave the older Vortec 5.7L under the hood. They don't overheat, but they constantly run very hot. Not to mention, they're wimpy. And many of those era Chevy trucks have hideous A/C that won't do the trick.
I used to run a fleet of Chevy vans with the 5.7L. In the Indiana summer heat, all 20-some of them did so poorly I lobbied the university to upgrade to Fords which they finally did 3 years later. At anything under about 10 mph, there wasn't enough airflow over the condenser and the A/C would trip the high side switch and start blowing hot. The clutch fan would engage, and (get this) there was so much drag from the fan that at full throttle, they wouldn't shift out of second. They would get up around redline, refuse to spin any more, and the computer never shifted.
Also had some 1998 6.5TD pickups in the fleet that would do the same A/C trick (but they shifted fine.)
Otherwise, all of the brands will do a decent job towing. They have spent so long trying to outdo each other that they're relatively equals in the function category. I had a 98 F150 4.6L that I ran until it had 245k on it with the only repair being a heater core that started leaking. I recently (2 years) bought an 02 F150-7700 with the 5.4L that has been a non-stop nitpicky nightmare. It tows great, but I get an Evap leak code about once a month, I've had to replace the manifolds twice, did a coil, can't get the parking brake to work right, and the 4x4 servo likes to stick when its cold. I think I'll trade it for something else soon.
Also have (well, dad has) an 04 and an 08 Dmax that are dreamboats.
General observations, YMMV:
Chevys use much lower quality interior materials. The seats in both of dad's trucks lasted less than 60k before splitting open the seams whereas all of my Fords weren't even showing wear until about 150k. I prefer the ergonomics of the Chevys, but you'll notice that all the buttons for things like the radio, climate control, etc are made with this rubbery coating that turns into pudding and wears off/starts feeling like an old piece of sticky tape.
Mechanically, they're both very similar. Most of the gas offerings will get you the 4L80E in the chevy and the 4R100 in the Ford. Both great. Same goes for rear axles: 10.5" in the chevy, 10.25" in the Ford. Overkill.
I might give up my 4x4 for a couple years and go back to a diesel van from either company. I really prefer vans, but getting one with 4x4 means an expensive conversion.
Both manufacturers offer an HD half-ton. My brother-in-law has a 1500HD chevy that is really hard to discern between a 2500; 8-lug wheels, 10.5" rear, 4L85E. I have the F150-7700 which has the 7-lug wheels, 4R100 and 10.25" rear. Both offerings are basically a half-ton truck with 3/4 ton guts stuffed in them. I have no problem towing 10k with mine, (rated for 8700) and he tows 8500 with his.