2011 Chrysler Town and Country 3.6

Any tips for improving mpg on it beyond the hypermiling basics? pretty impressed so far with this 3.6 compared to the 3.8 in my dads 2009 (he might get 21 on a trip, we are seeing about 25 thus far in mixed driving). he has a 2013 challenger v6 and got 32mpg with it on a road trip :banane58:



will a scangauge or something of the like work on this(maybe something newer and more plug and play)? im not sure 'what' the fuel mode button actually does (seems to change shift points). I've read it does quite a few things, though Im not sure if it actually does so.



thanks!

2011 Chrysler Town and Country 3.6