I had only Ford trucks until they started putting Cummin Diesel engines in Ram (no longer "Dodge") trucks and I've only had Ram trucks since then. The six speed auto in my currrent Ram is definately more reliable than the 4 speed auto in my previous Ram so the "more gears = less reliability" notion is not universal. Especially with Automatics because planetary gears are always meshed and don't "shift" from one set of teeth to another when ratios change.
You couldn't pay me to drive a Chevy/GMC truck today. They are so far behind what Ram and Ford offer now. I like Ford trucks, but I also like Diesel trucks. Until recently than meant Ram/Cummins was the only choice for me. The new 6.7L Ford-built (not Navistar built) Powerstroke is finally a decent diesel offering from Ford, so that makes the choice a little tougher for me. But I still prefer the overall looks of the Ram so it still gets the nod from me.
Since I prefer diesel for towing, that used to mean something bigger than a half-ton truck even though I don't need the payload. But recently, half-ton trucks have started to appear. Ram has one now, Nissan will have one next year, and supposedly Toyota will have one in 2017. No official word yet from Ford or Chevy on a half-ton diesel.
To complicate things, the Ram half-ton diesel does NOT use a Cummins engine. I love the truck, and all the write-ups on the engine seem very good. It has a lot of new-tech engineering. But still I'm holding judgement until its been used in the truck for a few years (it has been used in the Grand Cherokee for a few years prior to putting in the truck)
Oddly, Nissan is going to get a Cummins light-duty Diesel engine. It should be a good strong engine, but I can't stand the rest of the truck. There is no way I would own one even with an awesome cummins engine. Toyota makes a very good half-ton, but the details on their diesel option are still uncertain. Some rumors say it will be the same Cummins light-duty thats going in the Nissan, but that has yet to be verified.
If I had to make a choice right now, the Ram 1500 EcoDiesel would be at the top of my list. 2nd would be Ram 2500 Cummins with coil-spring rear suspension (smoothest ride for an HD truck). 3rd would be Ford SuperDuty 6.7 (Scorpion) PowerStroke.