I had a 2001 Dmax. No emissions at all on that truck.
It had 300 HP and 520 TQ.
It was cc, 4X4 DUALLY.
Best it ever got empty was almost 17 MPG.
I now have a practically identical 2011 Dmax
397 HP and 765 TQ.
The power increase is very noticeable.
The best it has done empty is 22 MPG.
Towing the 2011 does a little worse towing due to the fact that it has a lot more power, and it is used to go up the hills faster than the 2001 was able to. There is no free lunch.
I do think that if I were to take it easy towing and not go faster than the 2001 could, that the MPGs of the 2011 may be better...But that hasn't happened yet.:B I'm having too much fun to slow down!