My 1500 was assembled in Mexico. My 2500 was assembled in Ft. Wayne, IN ( other 2500 plant is in Flint, MI ). I liked the 2500 was assembled in Ft. Wayne only because I had a '98 2500 that also was done there and I really liked that pickup. I wasn't much concerned about my 1500 being assembled in Mexico. I long grew past that. When I ordered my 2013 Freightliner semi truck tractor, they were building in N.C and Mexico. The dealer didn't say anything, but later after it came in, he mentioned that they were keeping their fingers crossed it would be assembled in Mexico. That's right! Reason, they have more issue with trucks assembled in N.C. Well, true to form, it took the dealer 2 extra weeks to correct problems with my truck, and it was assembled in N.C. I have no clue if those guys at the plant were too concerned with going fishing, meeting at Hooters after work, or what, but they sure were not paying attention to their job. Missing brackets, extra parts for dealer final assembly all in disarray in the component box, etc.
I use my pickups to haul more than tow. And the 1500 just wasn't the ticket. The 2500 is vastly better, especially off road. But just in handling and overall experience, I much prefer the 2500 to the 1500. The 1500, to me, seemed like a car on steroids. Kinda like they had a 4 door El Camino in mind. That was the first 1/2 ton I had gotten since owning a '66 Chevy C-10 in the early 70's. I don't ever see a 1/2 ton in my future again.
Either way, the L96 6.0L in my 2500 has a long track record of being a reliable, strong, long lasting motor. Lots of internal design features that carried over from what GM learned in its racing side and Corvette side. The 2015 2500 6.0L totally blew the snot out of the 2015 Ram 2500 6.4L on the Ike Gauntlet test pull by almost a minute and a half up that mountain, and the 6.0 2500 had 300 more lb loaded on it (both were loaded to maximum GCWR). The Ram 6.4L had 60 more HP and 50 more lb of torque and an 8 speed. So it goes to show, that numbers on a glossy brochure don't always equate to real world performance.