I just traded my old 2001 2500 for a 2004.5 and am wondering about this tow/haul transmission. Does it work the same as my old 47re ie if you switch to tow/haul is that just an overdrive cutout or does something else happen? On my 47re I just hit the overdrive cutoff when I hit the bottom of a hill is this the same? The manual is pretty vague about how to use it. Thanks