I've ordered a 2014 3500 SLT BigHorn SRW 6. 7 3. 42 CC LB and read in one of Dodge's brochures that for 2014 they have an "auto disconnect" for the front axle on 4x4's. I asked my dealer but they didn't have a clue. Anyone have any idea what this is? It stated that it would increase MPG by 1...