I'm a mechanic at a Ford dealership and own two trucks a 2009 ram 1500 and I bought a 1997 ram 2500 gas truck in 2012 for pulling vehicles for side work at my garage. The 2500 was owned since 2005 by a Coworker at the dealership. 2500 is about to hit 200,000 miles it got new front end wearable parts at 115,000 miles transmission rebuilt at 147,000 miles other than that just routine maintenance and fluid changes.
Truck has been outdoors since the day it came from the dealer, has always been a worker and hauler at least since 2005. Bed is about shot from slamming engines and other heavy things in it and paint is kinda faded in spots but just a couple of small areas of surface rust nothing serious. I'd say they are pretty reliable.