The trucks listed were all gas burning half tons. Of the three the Ford with the FX-4 package is the hands down winner. The Ford with the 4x4 is not, its 2wd drive meaning left front and right rear wheel do the work, an FX-4 is all wheels working. The 5.4 don't make much power and don't get very good mileage either. The older ones did spit out spark plugs, not a cool deal.
Shocks on the power wagon are spot on, I replaced the shocks on my Dodge 3/4 ton with the Cummins. I used Blisteins gas shocks, some better but not worth it. I like the 8 speed in the Dodge too, plus it gets 20mpg with some power. I have a 6sp manual behind an LS2 in my GTO. First four are just regular 4 speed while the last two are overdrives to get the mileage well above 20mpg, not too bad for 400hp. Confused by now? Buy used and save