I have a Big Horn and both the AC and Heat seems to work fine. It was 117 one day that my truck sat in a parking lot all day. Put AC on max and 4 miles later, it was at 87. With the temp set at 70, 5 miles after that, I had to turn it off of max fan. No hack on my system.I know these forums usually have the people that have problems, but does anybody have a 19 and up ram that the AC/Heat works correctly without hack. I keep wanting to buy one but I need to quit reading these forums or I never will. I'm guess I'm more amazed that FCA hasn't done something about it.