On the dodge... Actually I don't think a Dodge is any more or less reliable than any other truck... Yeah, the rear end COULD have been from towing, although the 3.73 rear end should have been able to go forever.
But, I attribute the engine problems to the dealers, not the manufacturer... NINE visits, and every time they came up with something else... First it was the "non-factory" spark plugs - which were actually an alternative recommended for towing. Having them put in plugs cost $320, yes $320. From that point on, EVERYTHING they did was on the extended warranty... First they decided it was plug wires. It wasn't then it was an injector. It wasn't. THEN it was an intake manifold gasket. It wasn't. Then it was just reprogramming the computer. It wasn't. and on and on.... FINALLY, they decided on of the heads had a "problem", which it may have or may not. But, once it was changed, the light stayed off and a couple weeks later we dumped the truck.
105,000 miles. The bigger problems were that the thing had to be taken out of overdrive to tow, couldn't get past 65, and was dismal climbing hills like I-70 to the Eisenhower at higher altitude.
I'd buy a Dodge diesel or a Ford diesel or a Toyota diesel (if we had any) or a Nissan diesel (if there was a 3/4 ton). Just happened to find a Chevrolet equipped the way I wanted when we needed one.