MPG 2017 3500s pulling 22,800

My 12V was LOUD pulling 6 percent grades West Coast. We had to basically yell at each other. The 15 towing 23K and combined 33K is VERY quiet to where we can just talk normally. Yes you can hear the engine but it is no way loud. To compare to a 12V or 2nd gen 24V is not a fair comparison, not even close!