I have a 2.2petrol and a 3.2 v6
Overall the 3.2 has averaged 28-29 mpg on a recent 3500 mile trip
The 2.2 has averaged 24.5 mpg over 45000 miles.
I have driven a 3.2 auto and manual and I prefer an auto even though mines manual
Even though the 2.2 is dog slow, it feels better balanced even though both trucks are set up the same