I had a Nissan Titan, it was nothing but problems and Nissan wasn't very helpful at all.
I'm not a GM fan because of issues like Nissan, so never looked. Plus their 5.3L was a bit under powered and seen many coworkers upgrade after pulling a heavier TT with their 5.3L Silverado.
Looked at Rams but their payload was even worse than my 2008 Sport Trac 4WD payload. So technically they couldn't even tow as heavy as my Sport Trac without going over GVWR.
Looked at Ford and it had a good payload and good motor with low end torque. Then went to the 5.0L that put most to shame with it's low end torque, high end power, and good payload.
For me, if I went with Dodge, I'd need a 2500 5.4L to tow without going over GVWR. For me, if I went with Chevy, it would be a roll of the dice and I'd have to go with the 6.2L which is only on really heavy upper trim levels that reduce payload. Newer 2014 models have addressed the payload and lack of power for the 5.3L but it's still a GM with a roll of the dice.
Not a fan of Toyota as they seem to have a lot of the under built chassis issues I seen with my Titan as bed bouncing left to right over rough roads, along with low payload. Besides they seem very overpriced for what they are. If I was going to spend that type of cash, it would be on a 3/4 ton truck.
Wouldn't ever consider another Titan. Junk "in my opinion" and have worse gas milage than most 3/4 ton gassers.
Today if I had to replace my truck, it would be a 2500 Ram 6.4L or a Silverado 5.3L or 6.2L(as long as payload is adequate).
I wouldn't buy another F150 because for 2015 the F15Os have an aluminum body on a steel frame which scream dissimilar metal corrosion along with aluminum corrosion. I won't be the guinea pig on that truck. I may consider a F250/F350 though.